# TCCH Elcon charger troubleshooting and repair



## kennybobby (Aug 10, 2012)

Several of us dudes have been looking into some failed chargers to determine if repairs are possible. In the bad units we have seen that the input start relay and by-pass resistors have been overheated and failed. The main board has been traced and sketched up in another thread: http://www.diyelectriccar.com/forums/showthread.php/tcch-elcon-1-5kw-charger-schematics-89470.html 

We have made some good progress on tracing up the control board, and in the process found a defective FET driver that was pulling down the 12vdc supply. This may be the mechanism for causing the relay and bypass resistors to get so hot. 

The fet driver was drawing excess current from the 12vdc supply (the viper circuit) such that the viper went into re-start mode. But doing that would cause the start relay to lose hold-current and go open--now the full 120vac would be carried thru the 2 paralleled 150 ohm bypass resistors (~190 watts in 1 watt devices). 

We hooked up an oscilloscope and applied power to the viper and found it was in an infinite start-up loop and never able to kick in to regulation mode due to the Fet driver load. When we isolated the driver out of the load path, the viper came up and went into normal regulation. It appears to be a good device but should be swapped out anyway since it may have been overstressed. 

The control board has two separate 12vdc supplies generated by the viper--one for the analog section and one for the digital portion of the control board. The analog end shares power with the start relay and the digital end shares power with the output relay. 

If anything should cause the analog-end 12vdc supply on the control board to get pulled down low, it will take out the start relay and cause catastrophic failure of the charger due to the by-pass resistor configuration.


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## kennybobby (Aug 10, 2012)

*Found the culprit!*

Got the control board traced and posted the schematic. 

The 3846 SMPS chip has two outputs which control the two FET driver chips. The output stage of the B channel was internally shorted and causing the 12 volt supply to be pulled to ground. It caused the FET driver to turn on both the high and low side FETs of one totem pole (1/2 H-bridge) at the same time--that probably made some noise, it definitely blew some parts, but it should be possible to replace all the damaged components and repair this unit.

What would be the symptoms? Measured the resistance from +12 vdc supply to ground and it was only about 2 ohms. Removed the FET driver chip and the resistance went up to 90 ohms. Removed the 3846 SMPS chip and it went up to 1 Mohm.


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## Coulomb (Apr 22, 2009)

*Coulomb's index*

Coulomb's index

I've decided to put an index here to what I consider to be the more useful posts in this thread. Yes, it's mainly for my own use, but others may find it useful as well. PM me if you find a post you think is worth adding to this index.

*Re-assembly* notes, including the heaksink clamp removing tool, and *Reassembly* tips.
Transformer transplant.
Discussion on the reliability of the *bridge rectifier*, and effect of disconnecting mains under load. More here.
Drill this through if replacing the rectifiers on the high voltage models.
8 kW model *photos*.
Using *jumpers* in troubleshooting; more troubleshooting tips.
Tests for while the MOSFETs are not yet replaced.
SOT-23 devices marked *"A1t"*.
*"Desaturation"* protection schematic.
PCB with *C38* (large capacitor near MOSFETS) removed. Also C2 and C46 *small capacitors* nearby.
Improving *creepage* distance between MOSFET leads.
Input *relay* photos.
The mystery of the faint *crackling* sound solved.
How NOT to replace the *heatsink clamps*.
Start of discussion on replacement pre-charge resistors (*150Ω* 2-3 W near input relay). Continues for several posts. Using 750 mA slow blow fuses instead of a thermal fuse.
*Measurements* possible without taking out the main PCB. Next post has possible *repairs *without taking out the main PCB.
Replacing the *HF transformer*.
Q7, Q8 *PFC MOSFETs*
Cleaned-up *control board* (daughter board) image (large)
A and B PWM outputs; the U12 latch.
*Non-Viper* power supply model


For convenience, some links to revised *schematics* (in another thread):

*DC output* section schematic.
*Control* (daughter) board schematic.
*AC input* schematic.

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WARNING.

The DC bus capacitors collapse to around 10 V soon after the input (pre-charge bypass) relay clicks off, but the capacitors in the output section retain a nasty, possibly lethal bite for roughly a minute after turning off the power.

While there is an output relay, its contacts are bypassed with a resistor, which would limit any shock from touching both outputs to a likely non-lethal belt, but it is still dangerous, and you should take precautions.


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Harald Niessing said:


> As I told you both 150 ohm resistance of my 2.0kw charger were burned. This happened after the plug with the 7 pins (CAN-communication) has broken into two pieces (exactly there where the plug is sitting in the case/box of the charger)


So you're saying the plastic of the 7-pin round socket split in two? I've never seen that.



> and I plugged them together but unfortunately in the wrong position then the resistance burned and I heard little noise some where. Could you help me?


I've already mentioned the bridge rectifier. Have you checked that for short circuits?



> I like to know what could be happened? Which piece/s died and how could I localise it? As I told you I changed the resistance and they burned again. So there must be wrong something more?


Yes, a good chance is the bridge rectifier. Check also for flashover from one of the electrolytic capacitors to a small capacitor's lead. They sometimes use a larger-than-designed-for capacitor, and the clearance is sometimes too small. It could also be the main switching MOSFETS, or more likely the PFC MOSFET. You just have to trace the circuit through, using the schematic as a guide. No two repairs are the exact same.



> Where is the difference between the 1.5kw charger schematics and the 2.0kw charger schematics?


I'm not aware of any 2 kW charger schematics. From what I have seen, there doesn't seem to be a whole lot of difference; they just seem to use larger inductors in the 2.0 kW design, and different limits in the firmware. [ Edit: they also use a different number and possibly size of various electrolytic capacitors, from memory. ] The MOSFETs may be different part numbers with higher specifications, but I suspect not. The layout is a little different to accommodate the larger inductors. We're lucky to have the 1.5 kW schematics traced out. If you end up tracing part of the 2 kW schematic, it would be great to see what differences or even what commonality you can confirm.


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## Harald Niessing (Jul 20, 2014)

Thanks for your reply. 
But I am still searching to find the problem.
I forgot to tell you that the 7 pin plug haven't been in the plug they were loose (see the attachment) , so without any protection to each other. I think that the minus pole/pin and the plus pole/pin were in contact, so a short circuit happened. If that happened, what influence could have had this fact?

Another thing I would like to know is: Were generate the thing the 12Volt? 
Do you have an idea?

Thanks
Harald


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## kennybobby (Aug 10, 2012)

Oh sorry to hear--that is pitiful. The chassis connector has come loose and slid out and allowed the sockets to short circuit together.

The +12v and ground have a 2 Ohm resistor between the control board and the socket in the circular 7-pin, so those may have burned up.

i see in the second photo that the by-pass resistors near the input relay have started to scorch and burn the yellow staking compound--that is a classic symptom of the failure mode in which the relay gets turned off due to overheating of the low-voltage supply controller chip (the ViPer), and those resistors are left trying to carry all the current into the diode rectifier bridge mounted on the central rail of the heatsink. 

i'll have to look at the schematic again to see what other damage from the circular 7-pin is likely...


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## Coulomb (Apr 22, 2009)

Harald Niessing said:


> Another thing I would like to know is: Were generate the thing the 12Volt?


The 12 V is generated by a "Viper" chip. It's a tiny 8-pin DIP thing with a small copper heatsink sticking up.










You can tell this is a 1.5 kW charger; there are two large capacitors near the Viper. (2.5 kW chargers have three there.)

The schematic for this part of the circuit is in the schematics post; it's the one called low_voltage.JPG.

THe yellow thing with the "2" on it is the transformer that generates the two 12 V supplies. Note that the "isolated" output isn't all that isolated; there is some 3k of resistance from it to the negative end of the battery being charged.


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## LiFePO4 (Jan 30, 2013)

Greetings - I have been following this forum for years and love the info. But I have a PFC-2500 that is now not charging and I have not found anything like this mentioned.

The charger does everything it should during power-on and in fact turns on the output relay and shows a solid red LED. But it never puts out any current and will sit there for hours before it does a time-out error. It has been working fine for 2 1/2 years charging everyday.

I have been digging into the circuit (thanks to all on this thread for the schematics) and have yet to find anything. It is almost like it thinks the cells are full as far as SOC but why? I have checked the feedback resistor dividers and they are fine, etc.

I am hoping someone has seen this or has some ideas and I would be grateful for any feedback. I am a power EE by trade and understand the circuit and the one thing I keep coming to is the program IC (which, without knowing the FW you are making a lot of assumptions). Thanks


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## kennybobby (Aug 10, 2012)

Yeah but we now know the FW! (Thanks to Master Coulomb)

Did you check the output fuse?


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## Coulomb (Apr 22, 2009)

LiFePO4 said:


> I am hoping someone has seen this or has some ideas and I would be grateful for any feedback.


I have had the situation where I've set a voltage larger than the pack's voltage, it has a high current limit, and next to no current flows. I can't pin down exactly what's going on as yet, but it seems to want to see a moderate difference between the voltage setpoint and the pack voltage before meaningful current flows. But it sounds like in your situation, where it used to charge just fine, this doesn't apply.

It could possibly be the pack; if a cell is high resistance the voltage might rise with no effective current. Does the pack drive the vehicle? Do you see any current at all, or literally zero? If non-zero, is there any voltage rise on the pack? I think it can't be the output fuse, because then it would not see the battery voltage, and would bring up an error, and not close the output relay.

The next thing to do may be to set up a serial port connection to get information about what is happening. I don't have access right now to my schematics for the serial interface, and I can't remember if we published them. With a $10 circuit and a $20 serial to USB dongle, you could capture some 2400 bps data and post it here for us to analyze. That would tell us if it thinks it's too hot, or if it's trying to send current, and so on.


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## LiFePO4 (Jan 30, 2013)

Thanks for the replies. I did check all of the fuses (including the SM ones on the CB) and all are good. And my battery pack has been running normal and exhibits good ESR drop under load, so I don't think that is any issue

A little more clarity now that I think back; I have noticed lately that it does not "start" charging right away and pulses current for awhile (like minutes). I never gave that more thought until your mentioning the voltage difference. And there is more; I have some mornings seen the pack not fully charged back but it was at 80-90%.

When I "faked" the charger into thinking a battery was connected, I placed 4V at the input to the CB (which equates to 3.2V per cell) and the charger was trying to ramp up current. But when I plugged it back into the pack, I measured the sensed voltage going to the CB for both the DCDC output and pack and they were only 10mV different. The charger then just sat there happy as a pig in mud doing nothing.

I have read a few online issues where people report not getting the full charge with this charger and even one where it only would charge if the pack was below 50%. So where is all of this going? Well....

My charger puts out near 400V since I have 114 cells. I also noticed the divider is made with 2-390K leaded, 0.25W metal film resistors. Being a Power EE I remembered something; voltage coefficient of resistance and LEV. Basically, these resistors have a MAX operating volatge of ~250V independent of the power dissipation. A long exposure to high voltage (~200V for each resistor) leads to a decrease in resistance (both due to applied voltage and aging for a continuous applied voltage). And guess what; the resistors on the battery side are ALWAYS exposed to high voltage!

If these resistors are loosing resistance over time because of this, a higher than expected voltage shows up at the CB and the charger thinks there is more SOC than real. It can even think it is full and then will not do anything (or it will pulse once and think it is almost full). This would explain what others are seeing and why mine is acting this way. I also notice it seems worse when cold, and these resistors are lower at cold temps.

I am going to carefully measure the effective resistance and then change it if it is off. If this does indeed fix the issue, I will replace these resistors with ones designed for high voltage applications (they make them).

Thoughts? A little off the wall theory but everything else seems fine.


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## Coulomb (Apr 22, 2009)

LiFePO4 said:


> Thoughts? A little off the wall theory but everything else seems fine.


Your theory sounds quite plausible.

It could also explain a few things. These chargers have EEPROM values that are supposed to compensate for the tolerance of the measurement resistors. When you have multiple resistors in a chain as there are here, the tolerance adds. So you'd expect the voltage measurement to be a bit better than it actually is. If these resistors are being affected by the effect you describe, that could explain the lack of accuracy. (Of course, poor calibration procedures or inaccurate instruments could also explain it).

So I'll be very interested to hear the results of your investigations.

The calibration issue also implies that you should ideally calibrate your new resistors (saving new values to the EEPROM), or alternatively you may need to trim your new resistors so that they are the same value as the original resistors were when calibrated. An easy way to do this would be to examine the serial data stream; the battery voltage is reported among many other values. So you can trim your new resistors until the value in the data stream agrees with the value measured by a trusted meter. Of course, you might also get away with replacing the resistors with their nominal values, and hope for the best.


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## kennybobby (Aug 10, 2012)

LiFePO4 said:


> ...
> When I "faked" the charger into thinking a battery was connected, I placed 4V at the input to the CB (which equates to 3.2V per cell) and the charger was trying to ramp up current. But when I plugged it back into the pack, I measured the sensed voltage going to the CB for both the DCDC output and pack and they were only 10mV different. The charger then just sat there happy as a pig in mud doing nothing.


from which pins did you reference the 4V into the CB? How did you measure or detect the current ramp up?


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## LiFePO4 (Jan 30, 2013)

As far as getting the right resistor value, I do have one saving grace and that is the 10 programs; they are for changing the number of cells. Right now it is set at the MAX so I can't play with setting it higher. But if I over compensate the resistor so I have to use a "lower cell count" which to the charger is a smaller voltage it expects to see, I can then go to a higher cell count setting to "fine tune" the output voltage.

I injected the 4V at pin 31, which is the battery pack feedback. As far as current ramping, the charger was actually slowly ramping its output voltage starting at the "perceived" pack voltage and ramping all the way 420V, then stopping and repeating. It would be ramping up the voltage (and it was slow like 5V per second) and watching the current. This is how it would work to setup the output current for the CC mode.

But when plugged into the car battery, it never ramped and sat with the output set to the battery voltage with 0 current (I verified it was switching and running with expected gate drive voltages for the H-bridge). It was doing everything it should for setting a 0A output which tells me it thinks the battery is full.

I will look into getting a serial device eventually if this ends up being a pain or does not fix the issue.

Thanks

P.S. The charger never gives any error code either plugged into the battery pack, which is another indicator it seems to think everything is A-OK


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## LiFePO4 (Jan 30, 2013)

UPDATE: Well, changing the resistor value did nothing. I am running out of ideas...is there any form of a HW reset?


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## kennybobby (Aug 10, 2012)

LiFePO4 said:


> ...
> I injected the 4V at pin 31, which is the battery pack feedback.


And where did you reference the 4v return? There are a couple of different ground planes--and all 'grounds' are not the same.

Is the output relay actually closing the circuit or might it be defective?


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## LiFePO4 (Jan 30, 2013)

The 4V was referenced to the output ground (which is the local ground on the right side of the controller board). Yes, there are 3 "grounds" from what I can tell and they are not the same!

The output relay is switching but you have a very good point; it might not actually be closing the connection. I will check that and thanks.

P.S. It is down on my priority list since I have received my new Elcon charger so my PHEV is back up and running (but I want to repair the old one to have a backup).


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## pdove (Jan 9, 2012)

We want you to repair it since we are trying to learn all we can about this charger. Please post your results!


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## Sam DiMarco (Mar 30, 2011)

I have an ELCON 2500 that failed because I accidentally grounded DIN pins 1 and 3 going to the BMS control relay. When I did this I heard a 'POP' . Is this repairable?


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## Coulomb (Apr 22, 2009)

Sam DiMarco said:


> I have an ELCON 2500 that failed because I accidentally grounded DIN pins 1 and 3 going to the BMS control relay. When I did this I heard a 'POP' . Is this repairable?


That's a really disappointing part of the design; minor accidents like this should not cause things to blow up. They should provide some sort of current limiting to the power pin.

It sounds like this would be the Viper chip. It is certainly possible to buy this chip; I have a few myself, and they cost only a few dollars (excluding shipping). It's a bit of a pain getting the PCB out to get to this chip, and the black gunk they put on the PCB is irritating. But if you can overcome these two things, it is certainly repairable, assuming it's just that chip. This chip provides two sets of 12 V power, including power to the microcontroller via a small voltage regulator.








If you go poking around in there, be aware that the heat sink of the tiny Viper chip (8-pin DIP, the heat sink is a small postage stamp sized piece of copper soldered to four of the pins on one side) is at lethal potential. It's lethal when running, and probably for several minutes after the power is turned off. Caution!


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## Moltenmetal (Mar 20, 2014)

Oh man, thanks for that warning! Hope I never need that repair tip...will never again mess with those wires while the charger is running...


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## pdove (Jan 9, 2012)

Sam DiMarco said:


> I have an ELCON 2500 that failed because I accidentally grounded DIN pins 1 and 3 going to the BMS control relay. When I did this I heard a 'POP' . Is this repairable?


I don't see why this would hurt the viper chip. Shorting 12 volts to ground you most likely burned a cap and some resistors on the control board. It is possible this may be a minor repair. There is a two ohm resistor on pin three and a couple of caps across 12 v and ground that may have popped.


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## Sam DiMarco (Mar 30, 2011)

Thanks for the help.


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## pdove (Jan 9, 2012)

PM me and I can send you a schematic and some pictures.


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## Sam DiMarco (Mar 30, 2011)

I found R40,connected to pin 3 blown. What is the value? On line schematic shows a '2'. Is the K missing?


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## Coulomb (Apr 22, 2009)

Sam DiMarco said:


> I found R40,connected to pin 3 blown. What is the value? On line schematic shows a '2'. Is the K missing?


No, I believe it's 2 ohms. Maybe that's to turn it into a fuse. [ Edit: I have suspicions that it's an actual SMD fuse. ] 2K would not fuse from 12 V (< 0.1 watts power dissipation).

If the micro is still working (e.g. the red/green LED still lights), then this might be all that's wrong.

Edit: also check R39, on pin 2, depending on how you shorted pin 3 to ground.


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## pdove (Jan 9, 2012)

Coulomb is right R40 Is 2 ohms. I would check D9 and that big cap mounted on the back side that connects power and ground.


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## Sam DiMarco (Mar 30, 2011)

Thanks again for replying. My LED's are dead. At the time of the 'POP', there was no AC input just battery connected. When I apply 220ac I can hear a 'click'. No led's. How extensive is the damage. ELCON told me it is not repairable.


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## Coulomb (Apr 22, 2009)

Sam DiMarco said:


> Thanks again for replying. My LED's are dead. At the time of the 'POP', there was no AC input just battery connected. When I apply 220ac I can hear a 'click'. No led's. How extensive is the damage. ELCON told me it is not repairable.


Oh. Well, the click means that the Viper is OK after all; it provides the power for everything except actual charging, including pulling in the power relay (the click a second or so after applying power). So it can only be something associated with getting power to the micro and the 3-pin connector. My feeling is that it's probably quite repairable, and I don't know why they'd say it's not. Perhaps they'd prefer to sell you a new one.


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## Coulomb (Apr 22, 2009)

Sam DiMarco said:


> At the time of the 'POP', there was no AC input just battery connected. ... ELCON told me it is not repairable.


Oh, wait, I'm just processing that.

I think it may be possible (Pdove and KennyBobby, please give your opinions) that some combination of shorting the 7-pin connectors pins (which are referenced to pack negative) to some sort of ground might have applied battery potential to some sensitive electronics. If that happened, then it may have fried a lot of electronics, and may indeed be unrepairable. But if the pack is floating with respect to ground, that should not have happened.

The fact that the input relay pulls in doesn't involve much electronics; I think only the Viper and the input bridge rectifier are needed (and in fact only half of the latter needs to be working). So really the click doesn't rule out catastrophic failure of large parts of the electronics.

But I still think that this is quite unlikely, and that the charger is still most likely quite repairable.


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## pdove (Jan 9, 2012)

Coulomb said:


> I think it may be possible (Pdove and KennyBobby, please give your opinions) that some combination of shorting the 7-pin connectors pins (which are referenced to pack negative) to some sort of ground might have applied battery potential to some sensitive electronics.


Well if it clicks on application of AC power then the input relay is closing and at least analog 12volts is ok. You should be able to check between pins 22 and 23 on the connector connecting the control board to the power board and see if there is any digital 12 volt signal.

The LED's are driven by the microcontroller SPI bus. you may be able to connect some LED's to the front DIN connector and see if they blink. Pins 4 and 5 I believe. If so then you just damaged the LEDS and not the microcontroller. I would think the damage is minor based on what you are saying and the micro is probably ok. You can check for 3.3 volts on the black JTAG connector on the control board pins 1 and 5 as well. There is a hole in the case that will give you access to this port or you can take the cover off.


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## Sam DiMarco (Mar 30, 2011)

I got zero v at pins 22,23 and 1,5. Is microprocessor history? I could not find any components damaged aside from R40. It blew it's top but still had continuity. pdove do you do repairs?


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## Coulomb (Apr 22, 2009)

pdove said:


> You can check for 5 volts on the black JTAG connector on the control board pins 1 and 5 as well.


Except it's 3.3 V, right? Perhaps worth an edit?


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## Coulomb (Apr 22, 2009)

Sam DiMarco said:


> I got zero v at pins 22,23 and 1,5. Is microprocessor history?


Probably not. It can't be expected to work without power, and the fact that it has no power now suggests that it is probably safe from whatever caused the power to be lost. (Though it's still possible that there could have been some sort of surge that burned nearly everything.) In fact, if the processor is toast, it's not actually game over. It's a cheap part (a few dollars), and tricky but routine to replace it. We have images to reprogram it with, and even (in theory) the knowledge to replace the calibration values. We've only done about one of these processor replacements, and I can't remember where it's up to, but I think it was working well enough. But that's not game over.

What would be really tedious would be 75% of the chips being burned up by some "battery voltage across the low voltage power supply" scenario. We have part numbers for all of the chips in theory, and as long as none of the inductors are open circuit, all the burned chips and passives could be restored, but it might take so much labor that it would not be worth doing. I think this must be the scenario that Elcon are thinking of, but we disagree that it's necessarily at that point, at least with the clues we have so far.


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## pdove (Jan 9, 2012)

Thanks for catching my error. Yes the isolated side runs on 3.3 volts not 5. You may have fried the voltage regulator but I still say it's that big cap on the back side since you heard a pop. You may even have fried the on by the viper chip and if that is so you may not have 12 volts to this part of the card. Caps usually short don't they? At any rate I think it's repairable and I would give it a look if you don't think you can manage. 

Where are you cause I'm in Alabama? I think Adam shipped his to me for $12 or something. 

The one we soldered a new processor on and reprogrammed works like new. We put a brand new blank chip on it and then programmed the EEPROM and the flash on it.


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## Sam DiMarco (Mar 30, 2011)

pdove: I'm in Scottsdale AZ. I'll PM you with more info.
Sam


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## kennybobby (Aug 10, 2012)

On one of the ViPer repairs we also had to replace the diode and cap on one of the 12V outputs.

The 3kW repair that pdove mentioned involved replacing and reprogramming the microcontrollers for both the master and slave units.

We have another repair in progress that involved the FETs of the switching boost section. This one is turning into the labor sink hole that Coulomb mentioned--replaced the fets, numerous passive devices, the fet driver chips, the SMPS chip, the ViPer chip, the input relay and bypass resistors. May need to replace the PFC chip, etc... The failure took out so much that it is a tedioous process to test, find and replace all the affected components.


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## Coulomb (Apr 22, 2009)

I thought I posted this elsewhere, but I can't find it.

When re-assembling an Elcon/TC charger after having removed the main PCB from the heatsinks, it's important to use a suitable tool to prevent this sort of problem:










Note how the nearest MOSFET has been twisted, and is likely shorting its leads together.

The best solution seems to be to use a tool to prise the really strong heatsink clamps apart when positioning the clamps on the MOSFETS (also the diodes and bridge). Petrhaps a pair of spoons would do; I found a pair of screwdrivers was not terribly good. I found this pair of pieces of aluminum worked for me:










These are actually heat-sinks for diodes from an old welder, but obviously any scraps of metal about the right size would do. You can just squeeze the pieces of metal together to prise the clamps apart, and they are (just barely) not too big to get in the way of other parts of the charger. You may have to trim your scraps to size.

[ Edit:*the later models have slightly different clips, so 3 mm aluminium is too thick. So you'll need 2 mm, and aluminium may be too weak, so steel is preferred. ]


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## pdove (Jan 9, 2012)

Sam DiMarco said:


> I found R40,connected to pin 3 blown. What is the value? On line schematic shows a '2'. Is the K missing?


Received the units last night and took a quick look. The voltage regulator is out on the first one. The 3.3voltmsignal was reading 9.45volts. It possibly damaged other devices as well. The 12 volt and 15 volt signal were fine.

The other charger has good analog voltage 15 v but no 12 volt on the digital side. I measured across C45 measured 17.2 volts AC. Care to venture what that means?


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## Coulomb (Apr 22, 2009)

pdove said:


> I measured across C45 measured 17.2 volts AC. Care to venture what that means?


Well, assuming that your meter is blocking DC when measuring an AC range, surely it means that C45 is open. It's supposed to be smoothing out the ripple. If there is no DC measured across C45, as you indicated, then the diode has to be shorted or open. Combined with reading AC across C45, it has to be shorted.

Actually, if the diode is shorted, there could still be AC voltage across C45, and it may not be open circuit (just drawing a lot of current, almost choking the output of the Viper). So I'd check D13 first, and C45 next.


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## pdove (Jan 9, 2012)

Coulomb said:


> Well, assuming that your meter is blocking DC when measuring an AC range, surely it means that C45 is open. It's supposed to be smoothing out the ripple. If there is no DC measured across C45, as you indicated, then the diode has to be shorted or open. Combined with reading AC across C45, it has to be shorted.
> 
> Actually, if the diode is shorted, there could still be AC voltage across C45, and it may not be open circuit (just drawing a lot of current, almost choking the output of the Viper). So I'd check D13 first, and C45 next.


Update: ken replaced the inductor and the 10 ohm resistor on the input of the voltage regulator. Now we have twelve volts but the 3.3 is 7 something volts. 

I hooked up the FDI dongle to check the processor and they are fried on both chargers. Not sure what else is damaged with that high of a voltage yet.


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## Vectrix150V (Dec 13, 2013)

I've got a working 156V (13S flooded cells - 180V 11A max) 2Kw unit that I swapped the transformer and inductor from a 2Kw 120V (160V Max) unit - but have run into troubles with trimming the output voltage. (The 160V unit was unrepairable)

Due to the divider - both transformers produce 180V output.

I've tried the method here - http://www.diyelectriccar.com/forums/showthread.php/elcon-charger-voltage-adjust-51100.html BUT no luck - it either runs at 180V or doesn't detect the battery (sigh).

Is it possible to reprogram a 155V 13A lithium curve/program into it? The lead one seems strange - it is doing an absorb or equalisation routine - voltage pulses at end, not what I need (and it doesn't have the BMS control contacts either).

It works fine on a 13 series lead pack, with either transformer. Sigh.

Was a PITA to dissasemble and reassemble these things.


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## Coulomb (Apr 22, 2009)

Vectrix150V said:


> I've got a working 156V (13S flooded cells - 180V 11A max) 2Kw unit that I swapped the transformer and inductor from a 2Kw 120V (160V Max) unit - but have run into troubles with trimming the output voltage.


Ooh - a transformer transplant! We've thought about that, but I don't think that's been done before.



> (The 160V unit was unrepairable)


Heh. Paul, are you still in "I like the challenge" mode? 



> Due to the divider - both transformers produce 180V output.


I guess that's what we'd expect.



> I've tried the method here - http://www.diyelectriccar.com/forums/showthread.php/elcon-charger-voltage-adjust-51100.html BUT no luck - it either runs at 180V or doesn't detect the battery (sigh).
> 
> Is it possible to reprogram a 155V 13A lithium curve/program into it? The lead one seems strange - it is doing an absorb or equalisation routine - voltage pulses at end, not what I need (and it doesn't have the BMS control contacts either).


The short answer is yes, we have the technology to to this sort of thing now.



> Was a PITA to disassemble and reassemble these things.


Yes, they are a bit of a pain.

Unfortunately, reprogramming them is a different sort of pain. You will need to build two simple interface circuits, and you will need a serial USB dongle and an Arduino board of pretty much any sort. We can send the software you will need, but you'll need to have a bit of a software bent to do this. Having succeeded with the transformer transplant, you certainly have a hardware bent. Are you up for this additional challenge?

I was going to document what we know on the AEVA site once it's settled down (they're going through a painful database translation process at the moment). Maybe I should do it on DIY if you are ready.


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## pdove (Jan 9, 2012)

Coulomb said:


> Heh. Paul, are you still in "I like the challenge" mode?
> 
> Maybe I should do it on DIY if you are ready.


Im up for it. I have a few days off for the holidays.


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## pdove (Jan 9, 2012)

Vectrix150V said:


> Is it possible to reprogram a 155V 13A lithium curve/program into it? The lead one seems strange - it is doing an absorb or equalisation routine - voltage pulses at end, not what I need (and it doesn't have the BMS control contacts either).
> .


Yes you can send it to me or like Mike said we could teach you to do it. 

I have reprogrammed several.


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## Vectrix150V (Dec 13, 2013)

I'm ok with software, used to do a heap of pic microcontroller programming.

The 160v unit I stripped down, kept the semiconductors and magnetics but got rid of the rest unfortunately.

I'd be quite interested in the process, would save quite a bit of money instead of another $500+ for an appropriate charger.


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## pdove (Jan 9, 2012)

Vectrix150V said:


> I'd be quite interested in the process, would save quite a bit of money instead of another $500+ for an appropriate charger.


The code is Intel assembly. First you have to build a circuit using an arduino.
Next you have to write over some of your code with a routine that dumps memory. Then we have to repair the section we overwrote. We may need to read the EEPROM which requires writing some more code in to dump it. Then we modify the parameters we want compile it and write it back into your unit.

This is not a trivial exercise nor for the faint of heart.

If this is a CAN enabled charger it is easier but I was under the impression it was not.


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## Coulomb (Apr 22, 2009)

pdove said:


> The code is Intel assembly.


Most people think Pentium when you say "Intel processor". This is Intel 8051, an 8-bit architecture, from the early 1980s. The chips are modern, just the architecture is old, but still useful for 8-bit applications. I believe that NXP use this architecture because core designs are readily available, the assembler and other tools are available, and there are many people that know that architecture, so there is no need to invent a new one.


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## Vectrix150V (Dec 13, 2013)

That sounds extremely painful!

I noticed this post - http://www.diyelectriccar.com/forums/showpost.php?p=446313&postcount=119 - where a chip was programmed with lithium curves (I'm happy enough to do smd soldering).

Problem with sending the unit to the states is the postage cost - I could send the logic/control board - but the whole charger would be cost prohibitive.

Coulomb - if you want to document the process I'm happy to volunteer my charger for modification!


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## Coulomb (Apr 22, 2009)

Vectrix150V said:


> Problem with sending the unit to the states is the postage cost - I could send the logic/control board - but the whole charger would be cost prohibitive.


Yes, that is a problem. I had a charger's PCBs sent in a well-packed shoe box from Italy to Australia. The trouble is it's a royal pain getting the PCBs off, especially the high frequency transformer.

Maybe with time we'll figure out a relatively simple step by step procedure, so people with limited expertise can send just the PCBs to the experts at sane cost levels.



> Coulomb - if you want to document the process I'm happy to volunteer my charger for modification!


That's great. I'm happy to do it, but time is a problem at the moment. I'll get a week off over Christmas, so hopefully I can get a chunk of it done then.


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## pdove (Jan 9, 2012)

Coulomb said:


> Yes, that is a problem. I had a charger's PCBs sent in a well-packed shoe box from Italy to Australia. The trouble is it's a royal pain getting the PCBs off, especially the high frequency transformer.
> 
> Maybe with time we'll figure out a relatively simple step by step procedure, so people with limited expertise can send just the PCBs to the experts at sane cost levels.
> 
> ...


No need to ship it. We were going to document the process on the forum. 

Didn't you just want to reprogram it? Maybe I'm confused.


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## Coulomb (Apr 22, 2009)

pdove said:


> No need to ship it.


For this particular charger, looks like no. Sorry to confuse the issue.

But in general, it seems to me that the expense of moving these chargers around could limit the benefits of understanding how they work.

Not everyone can reprogram them, even with the best instructions, and not everyone can solder Surface Mount Devices.


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## pdove (Jan 9, 2012)

Coulomb;533505
Not everyone can reprogram them said:


> Oh, agreed. I got Ken to do it. He's pretty good.


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## Vectrix150V (Dec 13, 2013)

Yes - I was offering my charger as a reference to document the process to Coulomb as I think it may be a bit over and above what I can do.


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## pdove (Jan 9, 2012)

Vectrix150V said:


> Yes - I was offering my charger as a reference to document the process to Coulomb as I think it may be a bit over and above what I can do.


Well, if we develope the software and send it to you I am sure you can reprogram it. All you need is flash magic and an FDI dongle.


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## Coulomb (Apr 22, 2009)

pdove said:


> All you need is flash magic and an FDI dongle.


I forgot that there is this relatively easy way. The FDI dongles aren't all that expensive, and Flash Magic is free (as in beer) software.


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## Vectrix150V (Dec 13, 2013)

Excellent - Mouser.au lists one for $27.

Let me know how it all goes.


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## dimitri (May 16, 2008)

Another failure story  
My own Elcon 2500 bit the dust after 2 years of daily good service.
It just stopped working, no status light at all.
I opened it up, definite smell of burned insulation, but I can't see any obvious sign of burned parts. The input fuse is good, not sure what else to check.
Can anyone spot anything suspicious in the attached pic? Insulation on transformer leads is most charred, but I can't tell if this is normal for a 2 year old charger.


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## pdove (Jan 9, 2012)

Hard to tell from a picture.

However, if you could make some measurements it would help.

On the control board (board the is verticle behind the plastic cover) see if there is voltage (12v) on pins 22 and 23 where it connects to the main board. If so check and see if there is 3.3v on pin 1 and 5 of the black 5 pin connector at the top of te control board. Also check pins 1 and 8 on the control board where it connects to the main board it should be 15 volts.

Another thing to check is the input relay see if it closes when AC power is applied. Clear plastic. Check the voltage on the two resistors in front of the relay. They short out some times.


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## Coulomb (Apr 22, 2009)

dimitri said:


> Another failure story


I'd love to know how reliable these chargers are. Here, we see a lot of failures, but people don't report the possibly 100x more chargers that just keep on working year after year. Maybe we need a longevity thread, where people post things like "I have a XYZ model that's now 3.5 years old; never had any trouble with it".



> Can anyone spot anything suspicious in the attached pic?


It's hard to tell from those pictures; nothing stands out to me at a cursory glance. Except perhaps that a lot of the yellow gunk has discolored towards brown, as if this charger routinely got very hot.

Was it in a position where it would get good ventilation?

I think this also highlights the need for a "Now what?" or "My Elcon/TC charger stopped working - what do I do?" thread. Perhaps it can be a basic troubleshooting guide, with essentially a tree of things to check. Near the top would be "Can you see any LEDs on" and "Can you hear the input relay clicking on". Depending on the answer to those questions, you would be guided to checking the PFC voltage, testing the diode bridge, MOSFETs, PFC transistor and fast diodes, and so on. There could be a set of easy checks, like testing the various fuses for continuity, but in my experience, blown fuses are quite rare. There would also be a visual "sanity check", like if you see these two resistors burned up like this, go to this section because your 12 V power supply has failed.

Kenny, Paul, do you think you might be able to put one of these together? I'll be busy on the firmware thread for a while (still planning, but hopefully there will be something visible soon).


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## pdove (Jan 9, 2012)

What firmware thread are you working on?

Yes a trouble shooting guide would be good. I guess we could start a new thread or just do it here.


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## Coulomb (Apr 22, 2009)

pdove said:


> What firmware thread are you working on?


That would be this one: Elcon/TC Charger Firmware: Facts . No actual information yet, just the skeleton. I have a couple of weeks off, so hopefully I can do justice to it soon.



> Yes a trouble shooting guide would be good. I guess we could start a new thread or just do it here.


Thanks, Paul. I think a separate thread would be easier to find, but whatever suits.


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## dimitri (May 16, 2008)

pdove said:


> Hard to tell from a picture.
> 
> However, if you could make some measurements it would help.
> 
> ...


input relay works fine, 15v is present on pins 1-8 , but no 12v on pins 22-23 and no 3.3v on 5 pin connector.

sounds like 12v regulator is dead? is it easy to fix?


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## pdove (Jan 9, 2012)

dimitri said:


> sounds like 12v regulator is dead? is it easy to fix?


Let's not jump to conclusions. On the charger I just fixed L11 was bad.
It is located on the main PCB by the small yellow transformer that makes 12v.

If you have 15v then the viper is working and you probably have 12 v too.

Measure the voltage across C22 or C42. Should be 12V.

look at the Low Voltage supply schematic here:
http://www.diyelectriccar.com/forums/showthread.php?t=89470&highlight=schematics


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## dimitri (May 16, 2008)

pdove said:


> Let's not jump to conclusions. On the charger I just fixed L11 was bad.
> It is located on the main PCB by the small yellow transformer that makes 12v.


L11 is bad on my charger also. I have 18v before L11 on C44 and nothing afer L11 on C45.

Isn't 18v a bit too much? Maybe its OCV and will drop once L11 is fixed.

Is L11 a ferrite bead? I have some I can replace it with, not sure what current rating it needs and if DC resistance value is important?

Also, burning L11 is probably a result of overload or a short from control board, so it could happen again. Is it worth checking the current across L11?


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## kennybobby (Aug 10, 2012)

Yes i would wonder about some overload or shorting event to take out the coil L11. On two chargers in for repairs to pdove here it also fried the processor due to overvoltage out of the 3.3V regulator (which also fried), and a small 10R0 resistor on the control board. 

The biggest 'load' on that 12V supply is probably the coil of the output relay--not sure what is causing this failure...


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## dimitri (May 16, 2008)

I put an ammeter across L11 , it only has 1mA going thru.
With L11 shorted I have 17v on pins 22-23 and still no 3.3v on 5 pin connector.


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## pdove (Jan 9, 2012)

dimitri said:


> I put an ammeter across L11 , it only has 1mA going thru.
> With L11 shorted I have 17v on pins 22-23 and still no 3.3v on 5 pin connector.


 
The 3.3 v is made by the voltage regulator on the contol board close to the processor. (spx1117) I had to replace that as well on this charger I am working on. The cause of this failrue was pin 1 and 3 on the 7 pin front DIN connector got shorted together.

I would replace the inductor first and recheck the voltage before I jumped to conclusions about the 17V. There are several grounds on this charger and it's easy to get false readings if it's not complete.

It is possible the processor is fried as well but you may have gotten lucky. You can test the processor by putting 3.3 volts on pins 1 and 5 of the black 5 pin connector. I think they are labeled but if not groung is the pin closest to the front of the charger and voltage is on the other end. If the red LED on the control board starts blinking then the processor is ok.

After you replace the inductor then recheck the voltage if it is not 12 v then we may have to inspeact the viper circuit. If it is 12 v then replace the voltage regulator. And if the processor was bad in the last test you will need to replace it and possibly the temperature sensor LM20.


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## Coulomb (Apr 22, 2009)

pdove said:


> You can test the processor by putting 5 volts on pins 1 and 5 of the black 5 pin connector.


Oops! Pdove, I think I've had to correct this before... the processor runs at 3.3 V, not 5 V. Many of the inputs are 5 V tolerant, but I believe that Vcc max is about 3.6 V, like most chips designed to run at 3.3 V. I suspect that 5 V would damage the processor.

You can also test the processor without the 12 V supply working, or without the charger plugged into AC at all, by supplying 12 V to the appropriate pins of the 7 pin round connector. I notice this when I have my serial interface plugged in.

This could be useful if you have a front end (PFC stage) fault and want to know if it's worth attempting to repair it. If the processor is fried, then it's a lot of work to replace it and reprogram the blank replacement with new firmware. Elcon in California won't even attempt to repair a charger with a fried processor.


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## pdove (Jan 9, 2012)

Coulomb said:


> Oops! Pdove, I think I've had to correct this before... the processor runs at 3.3 V, not 5 V. Many of the inputs are 5 V tolerant, but I believe that Vcc max is about 3.6 V, like most chips designed to run at 3.3 V. I suspect that 5 V would damage the processor.
> 
> You can also test the processor without the 12 V supply working, or without the charger plugged into AC at all, by supplying 12 V to the appropriate pins of the 7 pin round connector. I notice this when I have my serial interface plugged in.
> 
> This could be useful if you have a front end (PFC stage) fault and want to know if it's worth attempting to repair it. If the processor is fried, then it's a lot of work to replace it and reprogram the blank replacement with new firmware. Elcon in California won't even attempt to repair a charger with a fried processor.


Sorry, you are right 5v might damage the processor (brain fart). Thanks for catching that Mike. 3.3 volts on pin 1 and 5 on the 5 pin black connector.

He said he put 17 on pins 22 and 23 when he shorted the inductor so I don't think the voltage regulator is working becauswe he said pins 1 and 5 read 0.


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## Coulomb (Apr 22, 2009)

dimitri said:


> Is L11 a ferrite bead? I have some I can replace it with, not sure what current rating it needs and if DC resistance value is important?


It has a marking code of 2R7J. I believe that this means its inductance is 2.7 uH, +- 5%. See How to identify inductor markings. Its DC resistance won't matter much, as (I'm guessing) the current on the 12 V supply would be quite light. The R in the marking doesn't indicate electrical resistance; it signifies the decimal point, as on resistors, but the units are microhenries rather than ohms. Any suitably sized replacement of 2.7 uH or larger and under an ohm of DC resistance should work. This should be close:

http://www.digikey.com/product-detail/en/1812R-272J/DN42127JCT-ND/1115674

The sample I measured had a DC resistance (in circuit) of around 0.5 ohms, so maybe these 0.75 ohm resistors are a little high in resistance. I'm guessing the size at 1812 imperial.

[ Edit: more careful measurement suggests a 1210 case. See next post (over page). ]


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## Coulomb (Apr 22, 2009)

Coulomb said:


> I'm guessing the size at 1812 imperial.


Actually, that might be a little large. More careful measurements put it at about 3.0 mm long, around 2.2 mm wide and high. 1812 is more like 4.5 mm long. So maybe it's a 1210 (imperial) package. Like this one:

http://www.digikey.com/product-detail/en/1210R-272J/DN42053JCT-ND/1115637

Sorry for the sloppy measurements. This one is 1.1 ohms resistance, which is a bit higher than I measured. I don't think it matters in this application, and if I unsoldered one, I'd probably find its actual resistance is higher than 0.5 ohms.


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## dimitri (May 16, 2008)

Well, I was not lucky, MCU is indeed fried. I applied 3.3V and it draws 170mA, which is too high, and MCU gets warm and there is no LED function, so that's the end of story for this charger as I am certainly not interested in replacing MCUs and reprogramming firmware. I was planning to upgrade my pack anyway and get EMW charger, I guess I will have to do it sooner than I thought.

If anyone wants this charger to play with or fix and resell, let me know.


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## pdove (Jan 9, 2012)

dimitri;536298
If anyone wants this charger to play with or fix and resell said:


> I will take it. I live in Alabama.


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## dimitri (May 16, 2008)

pdove said:


> I will take it. I live in Alabama.


Let me pack it in the box and see how much shipping will cost, I will PM you with shipping estimate.


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## kickngas (Feb 3, 2011)

After almost 2 years of flawless charging my 141v pack, my PFC1500 has stopped working. 
Today while heading to the USPS, I noticed my pack was not fully charged, so when I got back home, I tested the obvious(input power, LED status lights), then opened it up to find the main white fuse F3, on the input side, was not showing continuity. No visual signs of damage, and it smells springtime fresh. Any ideas??
I would love it if I could only replace the fuse knowing full well that it may be just a band aide. Does anyone know the specs of the F3 fuse and where I can get one? My guess is it is a slow blow 240v 15a.


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## pdove (Jan 9, 2012)

Put a jump wire over the fuse and see if it comes on.

It you want to test things incrementally? Then follow the instructions I gave dimitri.


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## kickngas (Feb 3, 2011)

Thanks pdove. Jumped the fuse, and...wait for it...let some smoke out. Came from a resistor standing beside the relay. Can I PM you to talk about repairs or advice?


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## kennybobby (Aug 10, 2012)

Good catch on that if it hasn't burned up anything or the relay yet. 

A smoking bypass resistor means the input relay is not making contact--either the viper is not working to supply the 12v for the relay coil, or the relay contacts are covered with vaporized plastic and carbon and not passing current, or the diode bridge is shorted internally.

Send pdove a message i'm sure he can help you or fix it for you especially if it is a lithium charger.


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## kickngas (Feb 3, 2011)

Yep, exactly what Paul said. We chatted about the charger., and I am sending it out to him tomorrow. Better he take a look at it rather than me hacking away blindly!


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## kickngas (Feb 3, 2011)

Paul has fixed my charger! It had a faulty bridge rectifier and a blown fuse.


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## pdove (Jan 9, 2012)

Both of Sam's chargers are repaired now as well. Had to replace the P89LPC938 chip micro-controller, the SPX1117 Voltage regulator and the LM20 temperature sensor on both chargers. One 2KW unit and one 2K5W unit both 144V nominal. Thanks be to kennybobby for solder work. Those parts are tiny.

Still working on Dimitris


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## racunniff (Jan 14, 2009)

pdove said:


> Both of Sam's chargers are repaired now as well. Had to replace the P89LPC938 chip micro-controller, the SPX1117 Voltage regulator and the LM20 temperature sensor on both chargers. One 2KW unit and one 2K5W unit both 144V nominal.
> 
> Still working on Dimitris


Is there any indication of what caused the failures in the first place? Inadequate cooling? Transient spikes? Something else? As an owner of an Elcon charger, I am understandably nervous.


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## pdove (Jan 9, 2012)

racunniff said:


> Is there any indication of what caused the failures in the first place? Inadequate cooling? Transient spikes? Something else? As an owner of an Elcon charger, I am understandably nervous.


I can only surmise. He said he had two units paralleled. One 2KW and one 2k5W and they started cycling on and off and then quit or something like that. They are not meant to be run like that. The 3kw, 4kw, 5kW etc units are paralleled but they have slave sw in the other half and don't use the enable line. I believe the digital ground is tied to battery ground so these control lines pin 1 and 3 enable and 12v should be isolated with a relay or optos like it shows in their manual.


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## Coulomb (Apr 22, 2009)

pdove said:


> I can only surmise. He said he had two units paralleled.


It does my brain in figuring what paralleling the outputs and paralleling the digital grounds will do. It seems that the two shunt resistors will be (somewhat) paralleled, so each charger doesn't know its own output, but will see an average of the two chargers' currents. I can imagine this causing the chargers to cycle rather wildly in current output.

Ah. Likely the two measurements will be somewhat off. So one charger may take most of the load. But it will measure only (very roughly) half the actual current (the average of its output and the zero from the other charger), and so may attempt to charge at twice what it is capable of. That could overheat it or burn out the MOSFETs. But that's not what was seen, unless the microcontroller happened to be most sensitive to heat.

Maybe the 12 V outputs became paralleled, so one had power pushed into its output. But I would not expect that to affect the 3.3 V voltage regulator.

So: all very confusing.


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## pdove (Jan 9, 2012)

Coulomb said:


> It does my brain in figuring what paralleling the outputs and paralleling the digital grounds will do. It seems that the two shunt resistors will be (somewhat) paralleled, so each charger doesn't know its own output, but will see an average of the two chargers' currents. I can imagine this causing the chargers to cycle rather wildly in current output.


Sorry to confuse. I left out pertinent information. I believe he said one was set for 50 cells and one for 48 or 49 so it's likely the voltage is what was causing then to wig out.


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## z_power (Dec 17, 2011)

I use two 1,5kW units with paralleled outputs and separate 2-5V control circuits. Their CV points are within 0.5V. I often reduce power of one unit to ~800W because of 10A circuit at my parking place. Haven't had any problems for 3 months of everyday use.


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## resultz (May 7, 2015)

Hi, I've been looking through this forum for a solution to my broken TC charger and was hoping someone had seen the same problem. It has worked fine for a couple of years, but now when I turn it on:
- the main LED stays illuminated
- the 2nd LED (under the yellow sticker) flashes quickly (2-3Hz)
- no current flows into the batteries (according to the BMS and my power meter)
- the BMS gets CAN responses from the charger, and the voltage appears accurate but the current claimed is 6.2A, which is wrong
- the CAN response indicates no errors (5th byte, status flags from TC charger CAN protocol document)
- the CAN response also includes a non-zero value for the 6th byte, which isn't documented but starts at 0x70 and I've seen it increment up to 0x76 over 10 minutes of operation

Everything seems to be working as expected, except it just doesn't deliver a charge 

The unit is a 2kW TCCH-H389-6, used to charge 94 x 90Ahr Thundersky cells. I've been testing it on and off for over a week now, and although it usually goes straight into the rapid flash failure mode, sometimes it will actually deliver charge current! Unfortunately it stops after less than 10 minutes.

There are reports of a similar problem on another forum (http://forums.aeva.asn.au/forums/problem-tc-charger_topic4349.html) but no solution or cause was discussed.

I've ordered a replacement for now, but would love to find the fault and fix it so I have a spare.

Many thanks for your time,
Michael


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## pdove (Jan 9, 2012)

you are not clear on the LED. I have never seen a unit with two LEDs and the light is supposed to flash an error pattern with 1 seconds between flashes. The error can be found in the manual.
http://www.zepiaenergy.dk/media/LIC_High_Power_Charger_Spec.pdf

The LED under the sticker is most likely the one on the control board. The rapid flashing usually means the software is stuck in a loop because of an error condition or fault which it can't handle. I have seen it once before when I was playing with the EEPROM values. Coulomb might have a more detailed answer.

We can look at the code and see what the charger is writing into those bytes but that may take some time. What do you want to do? You could ship it to me and I would be glad to take a look.


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## resultz (May 7, 2015)

Yes, the second LED is on the control board (I have popped open the box to look for issues). The main LED is not flashing anything - I believe solid means it is in bulk charge mode?

I've got a replacement on the way from China (TC) so the current one will become the spare if it can be fixed. I'm in Australia - where are you?

Thanks for the much more detailed user guide than I was able to find on the TC website - why is it so hard to find the right information?


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## Coulomb (Apr 22, 2009)

resultz said:


> The main LED is not flashing anything - I believe solid means it is in bulk charge mode?


Do you mean it's solid black (not lit) or solid red or solid green? It's a dual-color LED.

Solid red probably means bulk charging. But that doesn't agree with the tiny LED on the control board (a surface mount red LED) blinking rapidly.


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## resultz (May 7, 2015)

It's solid red while the control board LED is rapidly flashing red. On those few occasions I've found the charger to work, both LEDs flash at 1Hz and the flashing doesn't change when the charger drops to zero output after about 5 minutes or so.


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## pdove (Jan 9, 2012)

Like I said the control board flashing means the software is stuck in a loop if I remember correctly. Coulomb also told me that none of the states should be solid RED he said this means it's crashing which correlates to the flashing control board.

Mike do you remember this was last August if you keep your emails. 

Coulomb lives in Australia as well.


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## Coulomb (Apr 22, 2009)

pdove said:


> Mike do you remember this was last August if you keep your emails.


Paul (PDove) kindly found and forwarded the relevant emails to me.

I'm really rusty on this, and I think back in August was moderately early days for us. But it looks like it might be stuck in a loop that it enters just before attempting to turn on the relay. Or perhaps it's the whole process of turning on the relay, which takes some 3 seconds (when all is working).

You could help us a little by telling us whether you hear the faint click of the relay coming on.

I'll have to go check the code, but I think if it's not returning to the main loop, then it won't do CAN comms from then on. So that would cause the BMS to be upset.

Is there a light that comes on somewhere whenever there is CAN traffic? This would be in the BMS, I think. Ah, but you mentioned the sixth byte of the CAN packet, so you must have some way of knowing if and when CAN packets are arriving (or not). It would also be good to know if the CAN packets stop after a short while.

Are you handy with a multimeter? The August emails mention a diode and transistor associated with turning on the relay. It's possible that it's these components that have failed. We can show you photos of what to check. Warning: there are lethal voltages in these chargers, and yours is a higher voltage one as well. So don't go poking around in there if you're not familiar with the risks and the usual safety precautions.


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## Coulomb (Apr 22, 2009)

Coulomb said:


> I'll have to go check the code, but I think if it's not returning to the main loop, then it won't do CAN comms from then on.


I was wrong. It does check for received CAN messages, and seems to also check if it's time to send a periodic CAN message. So it could be stuck in this RELAY_SET function and still send CAN messages.


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## pdove (Jan 9, 2012)

Coulomb said:


> I was wrong. It does check for received CAN messages, and seems to also check if it's time to send a periodic CAN message. So it could be stuck in this RELAY_SET function and still send CAN messages.



Any clues as to what is in byte 6?


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## Coulomb (Apr 22, 2009)

pdove said:


> Any clues as to what is in byte 6?


No. My best commented disassembly has these 3 bytes always zeroed:


```
code:1356
code:1356             code_1356:                              ; CODE XREF: CAN_send_0+67j
code:1356 E4                          clr     A
code:1357 78 9B                       mov     R0, #CAN_set_V_copy ; Also CAN_msg0_stat+1
code:1359 F6                          mov     @R0, A
code:135A 08                          inc     R0
code:135B F6                          mov     @R0, A
code:135C 08                          inc     R0
code:135D F6                          mov     @R0, A
```
I note that the bytes are used by something else (the compiler seems to do that by itself, or maybe the authors did a sort of manual overlaying). So it's possible that this is a corruption caused by something involved in an interrupt.

More likely, there are many different versions of the firmware out there, and other firmwares do something else with that byte. I have one other CAN firmware in my collection, but it does the same thing (always clears the 3 spare bytes).

I was wrong about being wrong above - the RELAY_SET function processes CAN packets, but only received CAN packets. So if the charger really is sending CAN packets regularly, then it can't be stuck in that function, it has to be processing the main loop. Well, it does in the two firmware versions that I have. At least one of them dates back to 2009 or so.


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## Coulomb (Apr 22, 2009)

I thought it might be the case that my firmware is the same as the one in this faulty charger, that the other use of these thee bytes is accidental, and might actually tell us something useful.

But alas the other use is as the first byte of a floating point number, and 0x70 implies a magnitude of at least 10^29. So that can't be it. (I hope that made sense.)

I'll check the other firmware if I get time.


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## resultz (May 7, 2015)

Hehe, you guys certainly are knowledgable about the firmware and operation of these chargers - I wonder if the original designers have such a deep understanding?! I guess fixing problems ensures you learn about the problems, whereas simply designing something can result in only a superficial awareness of its issues. 

In answer to your original message, I have heard the faint click of a relay about 5-6 seconds into use (it sounded almost hesitant, as if the coil voltage was building up slowly rather than being switched). This is no longer occurring (the same as it is no longer charging) and is different from the transparent relay near the 240V input that comes on shortly after power is applied (in the first 2-3 seconds).

CAN messages from the charger are seen at regular (~1Hz) intervals, and if the BMS doesn't send CAN messages then the charger flashes the "communications error" sequence of red/green/red/green/red/green/red. This indicates to me that CAN message processing and generation is occurring. I've left the charger powered for at least 5 minutes and the CAN messages don't stop. Oh, and I'm able to monitor the CAN messages with an Orion CANdapter tapping into the CAN bus at the output of the Orion BMS, so I'm confident the traffic I'm seeing is correct.

I'm certainly handy with a multimeter, and careful with the lethal voltages in the car and charger (I'm an electronics engineer) so am happy to take any measurements you require. Shortly after I bought the car (a Blade Electron MkV) I had to rebuild much of the electrics, so I invested in some Cat IV equipment to do the job properly.

I found it odd that the contents of byte 6 were incrementing from 0x70, and if I powered off the unit for a while then restarted it, the number returned to somewhere near there before counting up again. Could the slow rate at which it climbs mean it is a temperature?


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## Coulomb (Apr 22, 2009)

resultz said:


> In answer to your original message, I have heard the faint click of a relay about 5-6 seconds into use (it sounded almost hesitant, as if the coil voltage was building up slowly rather than being switched). This is no longer occurring (the same as it is no longer charging) and is different from the transparent relay near the 240V input that comes on shortly after power is applied (in the first 2-3 seconds).


Ok, so it sounds like the conditions for entering stage 1 (actual charging) aren't being met, but otherwise it's running the main loop. The input relay is simply connected to one of the two 12 V power supplies, but it's not the same one as the processor runs off. So you have both 12 V power supplies; good.



> I've left the charger powered for at least 5 minutes and the CAN messages don't stop.


Right. So it can't be stuck in RELAY_SET(), unless the firmware has changed a lot.



> I'm certainly handy with a multimeter, and careful with the lethal voltages in the car and charger (I'm an electronics engineer) so am happy to take any measurements you require. Shortly after I bought the car (a Blade Electron MkV) I had to rebuild much of the electrics, so I invested in some Cat IV equipment to do the job properly.


Excellent! As soon as I have some time, I'll suggest some things to try.


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## Coulomb (Apr 22, 2009)

resultz said:


> I found it odd that the contents of byte 6 were incrementing from 0x70, and if I powered off the unit for a while then restarted it, the number returned to somewhere near there before counting up again. Could the slow rate at which it climbs mean it is a temperature?


It could well be. There are current set points and what not that advance linearly once per second by the same amount, but if it's really slow with a sort of memory effect, the it does sound like a temperature related value. Does it always (when cold) start at 0x70 though? From memory, 112 (0x70) is an important constant with the temperature scaling, so this could be a useful clue.


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## Coulomb (Apr 22, 2009)

I'm doing another repair. Classic burned-up pre-charge resistors. This one also has the bottom half of the bridge shorted (both diodes connected to the negative terminal). This sounds familiar; I wonder if this is a common pattern? When the bridge shorts like that, then the AC input is shorted past the pre-charge resistors, so nothing will get through to turn on the relay, and the pre-charge resistors are guaranteed a crispy demise.

Have others seen this pattern, or is this just one of many ways the input circuitry can fail?

I've noticed that when you disconnect these chargers at the mains end under load, the arc is pretty spectacular. I'm guessing that the energy for that spark/arc comes from the main PFC inductor (not the medium sized common mode chokes; these should have little leakage inductance), and so all this energy has to conduct through the bridge rectifier. They are moderately stout (from memory, 25 A and 1000 V rated; I feel bad replacing them with 800 V units now), but 800 V or 1000 V, they aren't going to last long if they regularly get the mains disconnected under load.

So maybe this is a failure mechanism: people control the charge by taking the power away with a relay, or switch, or just yanking out the power plug because it's time to go drive the EV, and the energy of the PFC inductor goes through the bridge to the arc at the switch/relay/plug and fries whichever half of the bridge needs to conduct to keep the current flowing (I think it might depend on the polarity of the mains at the time; if it happened to be close to a zero crossing, it might fry both halves of the bridge).

Plausible?

I wonder how other chargers handle this? There is a movistor in the Elcons, but it's before the bridge (presumably, to protect the charger from mains transients). Maybe there should be another one after the bridge?


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## pdove (Jan 9, 2012)

I repaired one that had this problem. Our theory, at least in the U.S., is that the AC input is backwards so the varister is on the wrong side for 120VAC.


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## Coulomb (Apr 22, 2009)

pdove said:


> Our theory, at least in the U.S., is that the AC input is backwards so the varister is on the wrong side for 120VAC.


Well, if you've only come across one like that, Paul, then it's not a big trend 

On the "backwards" mains wiring: it's all very confusing. Per this page:
http://www.emsd.gov.hk/emsd/eng/pps/New_Cable_Colour_Code/en/about6.html
it seems that the Chinese (or perhaps only in Hong Kong), white is not a standard color for an active or a neutral, though they do now have black as an active. But they used to have black as a neutral. Some countries such as Australia and South Africa, define black as neutral, and in Australia white is a good color for active. (So Australia is 100% different to the USA on the colours white and black. Sigh.) So are the Chinese trying to follow the US standard, and often get it wrong, or are they using their old standard with neutral as black? I'd be interested if anyone in the US can confirm wither their plugs are wired with black to the active pin, or black to neutral, on the plug. If the plug is molded, then presumably that end is correct. At least they use the international standard of green and yellow striped for earth.

Edit: According to this Wikipedia page, most countries are going to a brown / black / grey standard for actives. So now I really don't know how to wire cables with black and white wires to Australian plugs. Perhaps I*should just replace the black and white wired cable altogether.


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## Coulomb (Apr 22, 2009)

The bridge rectifier in these chargers is shown on KennyBobby's schematic as KBJ2510, a 25 A 1000 V unit. I was using a Vishay replacement, since that's what element14 in Australia stocks, but they only go to 800 V. Since I'm now thinking that the bridges may be getting destroyed by inductive kick back from the PFC inductor, or from the common mode inductors (current through them mostly goes through the bridge rectifier as well), I'm thinking I should not use an 800 V unit.

Fortunately, Diodes Inc make a compatible range that goes to 1000 V. For Australian readers, RS Components have them (cheaper than the 800 V units from element14, as it happens, but you have to buy in packs of 5):

http://au.rs-online.com/web/p/bridge-rectifiers/7514436/

These have the part number GBJ2510-F.

Newark claim to have them in stock, really cheap, but when I checked, there was no photo, no datasheet, and no details whatsoever other than a valid sounding description. I think Kenny mentioned in an email that Mouser have the originals in stock.


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## Moltenmetal (Mar 20, 2014)

OK: sounds like I'll have to install a switch to shut off the charger via the enable/disable signal wiring (used by the BMS to stop the charger) prior to unplugging it! Learning a great deal about how to keep my charger from dying by reading this thread- thanks a lot!


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## pdove (Jan 9, 2012)

Coulomb said:


> Well, if you've only come across one like that, Paul, then it's not a big trend


Every Charger I have opened has Black going to Neutral and White going to hot or Load as labeled on the PCB. As you stated, this is backwards for US wiring.


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## Coulomb (Apr 22, 2009)

Moltenmetal said:


> OK: sounds like I'll have to install a switch to shut off the charger via the enable/disable signal wiring ... prior to unplugging it!


Well, if it's some trouble, perhaps wait to see if my theory is accepted or shot down in flames. I don't think it could hurt, but it might not be needed, and might be a pain to use in practice.

One problem with the theory is that surely the bridge rectifier isn't being killed by excess current; the current would be the same as the working current. It would be getting killed by over-voltage, and upon reflection I think that the MOV should save it from that. MOVs are a bit soft for the first few milliseconds, but from what I've been reading, they should only overshoot by 10-20% in that time. That's still well under 600 V, which should be fine for a 1000 V or even an 800 V unit.


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## Coulomb (Apr 22, 2009)

Coulomb said:


> It would be getting killed by over-voltage, and upon reflection I think that the MOV should save it from that.


Just after I posted that, my eyes rested in a print of that part of the schematic. The common mode inductors, which are also moderately large, are between the MOV and the bridge rectifier. I was thinking that these would have negligible leakage inductance, but they would use a powdered iron core, which effectively means they have an air gap that can store energy. So perhaps it is these that are the cause of the problem, or at least part of the problem.

Those common mode things hurt my brain, but it seems to me that they are designed to look like a short circuit to changes from line to neutral, but a high inductance (hence high impedance) to common mode voltages (events that raise or lower active and neutral about the same amount). So it seems to me that whatever voltage the active half induces, the neutral half should more or less cancel it. But maybe they induce thousands of volts, and sometimes the difference is enough to damage the bridge rectifier under some circumstances.

I wondered about the 2.2 uF capacitor at the input to the charger, just after thefuse (across the MOV). Presumably, it's to power factor correct for some inductance. This could well be the main PFC inductor (immediately after the bridge rectifier). But if so, I assume that the inductance is higher for the 2.5 kW units than for the 1.5 kW units. I just checked, and it is marked 225, meaning 22 x 10^-5 F, or 2.2 uF. Maybe they forgot to change it when going from 1.5 to 2.5 kW, or maybe the inductance is about the same, just physically larger (such that the 2.5 kW units are on their sides, and connected to the heat sink). Or maybe I'm wrong about the common mode inductors (which look the same size to me on the 1.5 and 2.5 kW units), and the input capacitor is actually to compensate for their inductance. If that's right, then they really could be the cause of the bridge rectifier failures.

Of course, the other possibility is that it's just random failures of high power semiconductor, i.e. s#*t happens.

Another possibility is heat. I don't think that the Elcons are terribly good at reducing their power when the heatsink gets hot. So maybe the bridges are sometimes the first thing to go when things get hot.


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## Moltenmetal (Mar 20, 2014)

You'd think they'd design the charger to be robust against a line power failure, which could happen any time during charging. However, it seems logical that the PF correction circuitry could store a problematic amount of energy.

As far as terminating charge safely prior to disconnecting, that would be very easy for me to wire and use. It would simply be a momentary switch in my BMS cell loop, which you would press prior to unplugging. Since this is a way to guarantee that the particular problem Coulomb has theorized about would never happen except during a breaker trip or other unplanned power failure- since the charger is designed to have its charge cycle routinely terminated by a BMS- it would seem to be pretty safe insurance against an expensive potential charger failure.


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## Coulomb (Apr 22, 2009)

Now that I'm reassembling a repaired charger, I thought I'd write down some notes about disassembling and reassembling them.

Consider whether you really need to open it at all. A good sanity check is to measure the resistance from line to neutral at the plug. If it measures close to 75 ohms, you know you have a shorted bridge rectifier, but your pre-charge resistors are OK. Anything much less than 75 ohms means you have a shorted bridge rectifier and the pre-charge resistors have failed *low value*. Don't power up the charger with these type of faults. A good charger should measure at least a megohm both ways. There will be a 2.2 uF capacitor in there, so when you reverse the multimeter leads, it will go crazy for a while; short the line to neutral on the plug (not plugged in, of course!) briefly to discharge this capacitor and get a sane reading.

If you just want to know if it's going to work or blow up after some sort of incident, consider using a dual 30 V current limited power supply, putting the halves in series. Set each half for about 25 V and 2 A (so you'll be applying about 50 V at a maximum of 2 A). Connect positive and negative to line and neutral of the power plug (it doesn't matter the polarity). All going well, you should hear a click (maybe two clicks; when it first pulls in the relay through the pre-charge resistors, the 12 V can collapse briefly, then re-establish itself) and the main LED should start doing its red-green-R-G-R-black-B-B sequence indicating that the mains is out of spec. The current drawn should be around 50 mA (0.05 A). If this doesn't work, then you will indeed need to open the unit.

[ Edit: there is something else you can check without opening the unit. On the 7-pin round connector there is 12 V on pins 2 and 3, via some SMD fuses. If the resistance between these is low, say less than 10 ohms, then there is a large load on the 12 V auxiliary power supply. This could be because high voltage tangled with the 12 V circuit and fried everything digital. To know for sure, peel off the label covering the IPC 5-pin programming connector. The outside pins (pins 1 and 5) are Vcc (3V3) and DGND respectively. If these are low resistance, then it's likely that the processor and all the digital electronics is fried, and it's a huge repair job, probably requiring the flash programming of a new processor at least. PDove has done this, but I suspect he's the only person on the planet to have done so . So you might save yourself some effort opening up the case if you're not willing to do that. Of course, it might be something simple like a capacitor went short circuit, but it's unlikely. ]

NOTE: don't connect a battery to the mains plug; if there is an internal short or overcurrent, the mains fuse doesn't look like it could clear much DC; I'd say it is designed for AC only, and only to open in the most extreme of circumstances. I've never heard of an input fuse blowing.

*NOTE: the charger, when operating, and for up to two minutes after operating, contains dangerous voltages. Do not attempt to open the unit and poke around unless you know the basics of electrical safety.
*
Opening the unit involves taking out about 24 screws.Once the main cover is off, you can inspect for charred components, and check the input and output fuses. (As noted above, however, it's rare that these fuses blow, so repair is not likely to be a trivial fuse replacement.) Don't connect a battery to the charger output while testing on the bench. You can carefully power up and observe whether the input relay (the one that has a basically clear cover) pulls in. If it does, the internal power supply is working; if it does not, the internal power supply has failed.

There are a few other basic tests that can be done without pulling out the main PCB; I'll try and document them some other time.

It is possible, with great care, to replace the mains bridge rectifier without taking out the main PCB. It's worth the savings in time if you can do it.

Now, if you decide you do need to pull out the main PCB, you'll need some patience, a few slightly unusual tools, some heatsink compound (and a rag to clear away the stuff that seems to get everywhere, and more patience. To take out the main PCB, the various heatsinked components have to come off the main heatsink protrusion in the middle. In addition, two transformers have to come out, and these are thermally connected to the heatsink with white thermal compound. So you will need a lot of this to replace what is lost when the main PCB comes off. The two transformers come off with the main PCB; don't unsolder either transformer from the main PCB.

To get at the M3 nylock nuts, you'll need a good M3 socket. I found it extremely useful to get a long nosed socket something like this:

http://www.amazon.com/OEM-Tools-22269-Metric-Socket/dp/B00AXTJY64










You need either a 5.5 mm or 7/32" hex socket, as long as possible; mine was about 2" (50 mm) long. Even longer would be good. Mine was 1/4" drive, to go with a handle I have; choose the drive to suit what you use.

Both the mains and the DC output cables have to be removed to make enough space for the main PCB to come out. They will be covered with silicone, so remove most of this with a screwdriver or other suitable tool, and of course replace it when finished to preserve the IP rating of the charger.

When removing the heatsink clips, use a tool such as I describe here in post 37. I've since removed the diodes with a chisel and hammer, so the aluminum plates take up less space, and hacksawed out pieces so that only 2" (50 mm) engages with the heatsink clips. This allows me to clear other items much better.










When reassembling, I found it useful to use a small pair of long nosed pliers to place the nylock nut initially, then use a Philips screwdriver to turn the nut at least half a turn (the points of the screwdriver engage a little with the nylon of the nut), so that makes the nut take hold a tiny bit, so when you put the socket on, it doesn't knock the nut off and roll into inaccessible positions. Note that the screws for the main transformer are captive, but only in a slot, so they are free to move out of position in one direction. It's a bit of a fiddle to get all four screws to line up so that you have all four nuts engages a little before screwing them down tighter. Leave all the nuts quite loose until they all have a few turns on them, then tighten them all. Don't replace the cable to the 7-pin round connector before you have tightened the nut right under it.

PS: thanks to KennyBobby and PDove for most of these ideas.

*Edit 2016-Feb-14
*
I'm doing another repair, and I have some more suggestions. I thought I'd add them here, so they're not all over the thread.

A common situation is to find that the 12 V supply isn't working, so the processor gets no power and appears dead. It may not be the Viper20 chip that provides the 12 V supply, though that is common enough. Sometimes it's a load on one or other of the 12 V supplies. It's worth checking if the "isolated" 12 V supply is low resistance; an ohm meter between pins 22 and 23 of the 32 pin "connector" will establish this. If it is, it's likely that the charger is beyond repair. To check for certain, measure pin 1 to pin 5 of the 5-pin programming connector. As noted above, this can actually be done before opening the charger.

It could also be the other 12 V supply (pins 1 and 5 of the 32-pin connector are +12 V and GND respectively). Note that GND is not earth as in the earth lead of the power cable; this is running at lethal potential when the charger is running from the mains. DGND is also lethal when running. Often if the MOSFETs (Q1-Q4) are blown, they will take one or both of the drivers (U15 and U16) with them, and sometimes also U12 (the NOR gate), and/or U14 (the PWM chip). (Also check the diodes across the 10R gate resistors, Q12/16/17/21. The resistors should read very close to 10R; one of mine was about 2.4R.) Fortunately, U14 has a 10R resistor (R42) in series with its supply, so you can measure either side of R42 to see if U14 is pulling down the 12 V supply significantly. In my case, it measured about 25 ohms, but the 12 V supply read about 16 ohms, so it's likely OK.

L1 has a resistance of about 0.6 ohms, so again it's possible to tell whether the load is on the power supply end or the chip end of L1 by measuring the resistance to GND on either side. Unfortunately, the chip end of L1 has many chips: the drivers (U15, U16), the PWM chip (U14, already mentioned), a CMOS NOR gate (U12), but NOT U13 or the PFC chip (U2) (they're on the power supply end of L1). (The schematic is wrong about U2's power supply.) So you can get some clues as to what is loading the power supply that way.

Take extreme care removing the surface mount chips, especially the driver chips U15 and U16. These latter have holes under the board (for isolation, I believe), but it means they are well glued to the PCB by the black gunk, and it's easy to remove the PCB pads with the chip leads.

It's not necessary or even desirable to remove the machine screws that attach the heatsink to the output transformer (circled in red; the second one isn't visible in this photo). The machine bolts are very close to the transformer, and have slightly smaller heads than the other self tapping screws. Removing the nut circled in yellow is enough to remove the heatsink with the rest of the PCB.










[ Edit 2018/May: mentioned U12 often blows if the MOSFETs do, and what U12/U14 are. ]


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## Coulomb (Apr 22, 2009)

[ Edit: I no longer undo these heatsink screws, so the tip is now really this: don't bother undoing these screws. ]

Another little tip:










Ask me how I now this is a clever idea 

I don't even know if it's strictly necessary to undo these, but I think it made taking out and replacing the main PCB somewhat easier.

For later text searching: "Do up these bolts before replacing heatsink clamp".

Edit: the outer heatsink clamp behind the daughter board goes on after the middle clamp, if there is one (in the higher voltage units only, 288 V and above).


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## Coulomb (Apr 22, 2009)

For those working on the higher voltage chargers, another little tip (see photo).

Without this, I found that the little PCB would rise up with the screw, and the screw would not go into the heatsink.

It was a two person job replacing the diode stack, and required the patience of a saint. But I got there in the end.


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## Coulomb (Apr 22, 2009)

I have been wondering what the second relay is about at the output end of the charger. At first, I thought it was something to do with the KSI (Key Switch Interlock" function. But inspection of a charger's PCB indicates that the two relays are actually in parallel with each other. So this is about higher current for the lower voltage models! I note that the 1.5 kW models for 72/48/36/24 V have maximum currents of 16/25/33/40 A, and the relays are rated at 20 A (for the normally open contacts; 10 A for the normally closed). So for the 48 and lower voltage units, they must populate the second relay to double the current capability to 40 A.

But what about the 2 kW units? Surely these will exceed 40 A at 24 V? Well, these units are not available in less than 48 V, where the current limit is 35 A. Simple!

As for the "key switch interlock" using the green wire: I don't see this very often any more. As others have pointed out, it has a fatal flaw: when the charger stops charging, the state of the green wire is the same as when there is no power applied. So you can still drive off with the AC plug inserted, in the common case where the charge has completed! Duh. So why do they do such a crazy thing? Simple: they are making use of the normally closed contact of the relay. The battery connects to either the output of the charger, or the green wire. When not charging (either before charging is started or after it is complete), there is pack voltage (from the battery) at the green wire. When charging, there is no pack voltage on this pin. It seems that they provide this "feature" merely because it's almost no effort to provide it; the relays have a normally closed contact that would otherwise be unused. It would seem that this is not something that is carefully designed, or that they carelessly designed and is an easy thing to fix.

So I think we go back to ignoring the green wire (if it's even provided), although it does have one useful feature (again, probably not designed that way). When the charger isn't charging, the green and red output wires are connected together by the normally closed contact, *via the DC output fuse*. So this is a way of testing the DC output fuse, without opening the charger. (Of course, this only works if you have a model with the green wire fitted.)

So that clears up two issues in my mind: why the key switch interlock logic is flawed, and why there is provision for a second relay on the board, that never seems to be populated. (I never see the 48 or lower volt models, since these are not useful in normal electric cars.)

You can see in the photo that in this charger, it never had the green wire, as there isn't even a screw provided for the middle terminal. You can also see that a lot of the tracks to the second relay are parallel to each other, suggesting that the contacts and coils are in parallel.

The silk screen suggests that there is a sixth connection to the relay, connecting to the common of the contacts, at the very right hand end. This would be silly, putting the common (with battery positive) right next to the coil connections, but these right hand pads don't seem to be connected. Maybe they are on some relay models, but not the one I checked today, and not via the PCB.


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## Coulomb (Apr 22, 2009)

I have another theory about how the bridge rectifier may be failing. This one is also a bit of a long shot, I think.

It could be when the user *reconnects* the charger, after the main capacitor voltage has decreased significantly, *but before* the 12 V power supply drops out. So the pre-charge resistors are still shorted by the input relay. When the mains is re-applied, the bridge rectifier has to take the full in-rush current of re-charging the main capacitors (which are 2 x 220 uF paralleled for the 1500 W models, or 3 x 220 uF for the 2000/2500 W models). So this takes them from say 40-50 V (still enough to keep the Viper running) to 170 V (120 V mains) or 340 V (240 V mains). Near the peaks of the mains cycles, this inrush current could be quite considerable. Near the zero crossings, the >= 40 V across the bus capacitors will reverse bias the bridge rectifiers, so no inrush current will flow. In between, there will be between nothing and very considerable in-rush currents. So this would introduce an indeterminacy to the problem, suggesting why it hasn't been enough of an issue to have been corrected by now. The indeterminacy / randomness would be exaggerated by the user having to wait such a long time before it is safe to reconnect (it seems to me to be about 30 seconds). People's patience waiting for the charger to stop would naturally be quite variable. Sometimes, the charger is buried in a car, so you can't see the red/green LED, and may not be able to hear the soft "tink" sound of the input relay disconnecting. So then it becomes truly random: "oh hell that has to be long enough... "<<plug>> <<splat>>. Assuming that the bridge rectifier fails shorted (AC input to other AC input), there will be no DC bus voltage, so there will be no 12 V supply, so the mains fuse doesn't blow, and the pre-charge resistors then fry.

A nice corollary of this theory (if indeed it is right), is that there is a possible improvement: use a beefier (higher *current* rating) bridge rectifier. There are 40 A and 45 A versions available in the same style of package (just with metal showing, instead of being all glass passivated). Here is one such:

http://www.newark.com/vishay-genera...45/bridge-rectifier-1phase-40a-1kv/dp/79R2489










So in summary, the theories about frying the pre-charge resistors are:



Overheating. The Viper chip shuts down to save itself, but this opens the input relay, so the full mains current runs through the pre-charge resistors, and they fry.
Inductive kickback. Either the main PFC inductor or the common mode choke inductors, or both, cause a large voltage spike that takes out the bridge rectifier, causing a short AC in to other AC in. This drops out the DC bus, hence the 12 V, hence the input relay, and the pre-charge resistors end up across the mains, and they burn up.
Premature re-connect. The user reconnects the mains while the DC bus capacitors have discharged a lot, but the Viper is still running, so the input relay is still shorting the pre-charge resistors. The resulting in-rush current overloads the bridge rectifier, which shorts AC in to AC in. As with the inductive kickback, this results in the pre-charge resistors ending up across the mains.
The problems with the pre-charge resistors seems to be exacerbated by the manufacturer's choice of carbon resistors for this role. They have been seen to *reduce* in resistance with excess heat, which of course makes them draw more current. Usually, this is not enough to blow the 20 A input fuses. This can result in enough heat to cause the nearby input relay to crumble to charcoal, as we've seen. Wirewound types would appear to be more suitable in this role.


In all three scenarios, the bridge rectifier may be damaged / shorted. However, in the last two scenarios (my theories), it's the shorting of the bridge rectifier that initiates the problem. So if it is found that the bridge rectifier is commonly not shorted AC in to other AC in, then my theories are disproved. If you have a charger with a shorted bridge rectifier, it is possible to detect this IF the pre-charge resistors have not failed open circuit (which they often do, merely by crumbling apart). With a shorted bridge rectifier, you will essentially read the value of the pre-charge resistors from the line to neutral pins of the mains plug. So if you read around 75 ohms, or really anything from about twenty ohms to about a thousand ohms, then you have a shorted bridge rectifier, and should not plug it in. If the bridge rectifier is good, you should read some megohms in both directions, changing rapidly. If you read infinite resistance immediately both directions, then either the input fuse or something else has opened circuit, and the charger won't work but should be safe enough to plug in and try anyway.


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## pdove (Jan 9, 2012)

Maybe is was lightning.

I looked up the details on the one I fixed with this problem and all I replaced was the Bridge Rectifier and the input fuse.


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## Ruudi (Dec 17, 2009)

Hello 

Thank you very much for the trouble you have seen and info you have been sharing here for this type of charger.
I have two 8kW tcchargers one is on my car and working well, witch I use if I charge at charging station from mennekes connector witch is here 3 phases 3 x 32A 400V AC (between phases). And then I have paralleled on the battery side 3,3kW chinese charger with it and they work fine together.

Other one I have 8kW 72V tccharger, witch had accidently in race hurry, connected between phases in europe that means 400V AC. It consists of 4 2kW modules. It has two sides two heatsinks with two AC ventilators. One heatsink has two 2kW units on it.
Strangely only one module was hurt and of course it had to be the master module.
There was 1 of three big 220uF electrolytic capacitor blown, relay contacts welded together, rectifiyer bridge shorted and 30A fuse blown. Those components I have changed and connected it to the grid, it started up but it doesn't work properly no more. One (slave) side seems like ok its LED blinks red_green like it should when battery is disconnected. Other unit had only green light blinking. And master control board has red led blinking.
I have read your suggestions on repairs, and problems those chargers have. All systems seem to be ok except Low voltage SMPS gives out too big voltages. Here are my measurements:
Testing with 2 lab supplys in serial 52V current the charger took: 70mA
Low voltage SMPS: control board output 13,9V
and relay output 15,3V measured microprocessor voltage from black socket it was 3,3V
viper control circuit IC: on pin 2 =13,3V and pin 4: 1,98V
does it help if I change the viper IC I think it works but why does it give so high voltages? Does it matter for the control board uP?
I gave 12V from control pins and the control boards small red led started blinking the same as with 50V power on main power wires.


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## pdove (Jan 9, 2012)

Not sure I completely understood. Does the control board LED blink fast or slow? If the code is running normally it should blink once a second. If not then it blinks very rapidly once every 100 ms.

Those voltages are normal the viper seems to work just fine.


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## Coulomb (Apr 22, 2009)

Lada said:


> Other one I have 8kW 72V tccharger, whitch had accidentally in race hurry, connected between phases in europe that means 400V AC. It consists of 4 2kW modules. It has two sides two radiators with two AC ventilators. One radiator has two 2kW units on it.
> Strangely only one module was hurt and of course it had to be the master module.


That is pretty amazing (that only one charger unit of the four blew).



> There was 1 of three big 220uF electrolytic capacitor blown, relay contacts welded together, rectifiyer bridge shorted and 30A fuse blown. Those components I have changed and connected it to the grid, it started up ...


Well done! I'm so glad we as a community could help someone else repair a charger. Or at least come very close.



> but it doesn't work properly no more. One (slave) side seems like ok its LED blinks red_green like it should when battery is disconnected. Other unit had only green light blinking.


So it sounds like the microcontroller is working fine. Is it possible that the red part of the red/green LED is blown / not connected somehow?



> And master control board has red led blinking.


It should always be blinking. From memory, it blinks slowly (1 change per second) normally, but quickly 10 changes per second) in "state zero" when it is waiting to connect to a battery. [ Edit: as discussed next page, the slaves don't blink this LED; for slaves this LED is on unblinking when the output relay is on. ]



> I have read your suggestions on repairs, and problems those chargers have. All systems seem to be ok except Low voltage SMPS gives out too big voltages.


As PDove mentions below, these are OK. The "12 V" is very approximate. There is a 68 ohm resistor in series with the input relay, to take up the extra 3 V (and then some, I suspect) of applied voltage.



> Testing with 2 lab supplies in series 52V current the charger took: 70mA


That's slightly higher than the ~ 50 mA that I usually see. Nothing to worry about there.

I think the next stage is to try and read some serial data coming from the master. There will hopefully be valuable clues in there as to why it is staying in state zero (assuming that it is; with no battery connected, it should stay in state zero). Are you able to monitor the serial data stream from the 7-pin connector? Because it's a master, it might be best to connect to the 2.54 mm spacing connector on the control board, rather than the 7-pin round connector itself. From one of your photos, it looks like you are already doing something with the 7-pin connection.


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## Ruudi (Dec 17, 2009)

Coulomb said:


> So it sounds like the microcontroller is working fine. Is it possible that the red part of the red/green LED is blown / not connected somehow?
> 
> 
> It should always be blinking. From memory, it blinks slowly (1 cycle per second) normally, but quickly (5-10 cycles per second) in "state zero" when it is waiting to connect to a battery.
> ...



I connected RED/GREEN led wire and checked by multimeter those connections.

I didn't know that small LED on control board should be blinking. On the other slave control modules small square red led didn't blink that's why I thought it's a problem. Maybe I'll try to put it together and connect to the batteries and try to charge?

How can I read the serial data? I have arduino mega. Somewhere I have usb<->ttl module also is this what i need?


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## Ruudi (Dec 17, 2009)

pdove said:


> Not sure I completely understood. Does the control board LED blink fast or slow? If the code is running normally it should blink once a second. If not then it blinks very rapidly once every 100 ms.
> 
> Those voltages are normal the viper seems to work just fine.


It blinks slow about 1Hz but only on master control module on slave modules witch this charger has three they don't blink at all.

Good to know that, low voltage power supply is ok. Isn't the charger, well made when it survived 400V? So big overvoltage and it didn't let it destroy control board processor.


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## Coulomb (Apr 22, 2009)

Lada said:


> How can I read the serial data?


Good point, I forgot to post that. I've added a new post to the Firmware Facts thread.



> I have arduino mega.


That's needed for flash programming, but not for accessing the serial data.



> Somewhere I have usb<->ttl module also is this what i need?


You'll need a USB to serial interface, I think that's what you meant. But you also need a small interface board; the Elcon/TC chargers are not RS232 compatible.


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## Coulomb (Apr 22, 2009)

Lada said:


> I didn't know that small LED on control board should be blinking. On the other slave control modules small square red led didn't blink that's why I thought it's a problem.


Huh. I have a master/slave charger, but never noticed that the slave doesn't flash its control board LED.

I've just checked the firmware, and indeed, on slaves, the small control board LED only comes on (doesn't flash) when the output relay is on. So this is normal for slaves, but not for masters.



> Maybe I'll try to put it together and connect to the batteries and try to charge?


I know what a job that is: greasing up all the parts that need thermal grease, guiding the PCB back over the heatsink protrusion, lining everything up, tightening all the nuts (some are hard to get at), using a special took to get the heat-sink clamps back on safely, re-doing a cable tie on the main transformer, reconnecting the input and output cables, adding silicone grease, and putting back 24 screws. Oh, all that times four for your four-unit charger. Probably you can skip a few of those steps just for testing, and you can start with just the master unit.

But yes, I think it's time for that. My last test with batteries did not go so well, I hope you have better luck.


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## Ruudi (Dec 17, 2009)

I checked out on my working charger on the car. The control board small red led doesn't light at all when charger is connected to the network (switched on) and batteries are not connected. When charger is charging the led is on always.
Seems like charger that's in repair at the moment has some problems still.


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## Coulomb (Apr 22, 2009)

Lada said:


> The control board small red led doesn't light at all when charger is connected to the network (switched on) and batteries are not connected. When charger is charging the led is on always.


That's exactly what I expect of the slave unit. But the master unit has different firmware, and always flashes the light. Perhaps you can confirm that in your working charger.



> Seems like charger that's in repair at the moment has some problems still.


Not that I can see.


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## Ruudi (Dec 17, 2009)

Hi, sorry, in my previous post I made a big mistake. I didn't pay attention that the charger is originally "upside down" master control board is in the bottom! 

That charger witch is on my workshop table I put together allready one time wrong way because it is possible. Top and bottom pieces screw holes are the same. 

So I was watching slave module small red led and now I'll try to put it together and test on the car.

Thank you pdove and Coloumb for very fast responses and for showing the way what to do next!


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## Ruudi (Dec 17, 2009)

Yesterday evening I put the repaired charger on the car for a test. And I found out that I had power control pot wires all wrong because the socket was broken and I soldered wires there. If I got figured out the right enable pin then it started working!
Now I'll try to separate one 2kW module phase supply because I cannot get over 32A from the charging points so I could not get maximum charging power. The idea came from other thread where somebody already tried that.
http://www.diyelectriccar.com/forums/showthread.php/elcon-tc-charger-6-kw-idea-135105.html


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## Coulomb (Apr 22, 2009)

I've added a few more troubleshooting and repair tips to an earlier post (just so my hints are nearer each other and hopefully easier to find):

http://www.diyelectriccar.com/forums/showthread.php?p=662065#post662065

The additions are the third paragraph and the last section.


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## Coulomb (Apr 22, 2009)

*Warning: if the mains input is connected to actual mains, the "GND" mentioned here is at lethal potential to the ground pin of the mains, and your body. In other words:
GND is HOT!
I believe that these jumpers are only intended for use with a current limited power supply of about 50 V.*

I've finally sussed out the use of the three main jumpers on the Elcon/TC charger daughter board (the one with most of the chips on it, including the processor and small red LED).

J8: short to disable the PFC stage. This is a good thing when debugging with a 50 V current limited power supply, because the MOSFETs will switch at 50 V rather than 385 V.

J7: Short to force 240 V mains detection. Without this jumper, the mains sensing circuitry will decide that your 50 V power supply is too low, and will disable both the PFC stage, and the PWM stage. So the MOSFETs won't switch at all.

J3: Without a battery detected, the microcontroller won't enable any switching. By inserting a jumper with a 1.8 kΩ resistor (see below), you will get a moderate duty cycle. This is ideal for testing. [ Edit: I used to recommend a 3.3 kΩ resistor for a very low duty cycle, but on some chargers, there isn't enough voltage to get the UC3846 to start generating pulses. ]

[ Edit: so the sensible combination of jumpers is as follows, in order:
1) *All jumpers out*. 50 V across the main MOSFETs, but they are not switching. Good for finding shorted MOSFETs. Leave the power supply current limit at 0.5 A or less.
2a) Optional. *Only J3 in*. For the truly cautious, this will give the MOSFETs a short burst of switching, then immediately stop switching them (as it realizes that the mains is not present). You should be able to measure part of the voltage from the next step at the output, slowly decaying. It might be only a half or even a quarter, so a peak of 4-12% of maximum voltage, or 5-16% of nominal voltage.
2b) *All jumpers in*. 50 V across the MOSFETs, which are now switching. You should see some 15% of maximum rated voltage (about 20% of nominal voltage) at the charger output (negative output terminal and PCB pad, see below). Power supply limit can stay at 0.5 A or less.

At this point, you should be confident that the MOSFETs are switching properly, because the energy in the bus capacitors is about to increase about 8² = 64 times. Use a DSO if there is any doubt.

3) J7 in, *J8 out, J3 out*. Now there should be ~ 385 V on the DC bus (the MOSFET power supply), but the MOSFETs are not switching yet. The power supply current limit needs to be at least 2 A, preferably 2.5 A, to get started. It may take ~10 seconds to get close to maximum bus voltage, at which point the current should fall to around half an amp (it jumps around a lot on my power supply, which is two 25 V supplies in series).
4) J7 in, J8 out, *J3 in*. Now there should be ~385 V on the DC bus, and the MOSFETs should be switching. The power supply limit needs to be at least 2.5 A, preferably 3 A. Now you should read about 110% of the maximum rated voltage (about 150% of nominal voltage) at the charger output. This could exceed the voltage rating of the output capacitors; if so, don't leave it running like this for very long.
If it passes all this, it's time to reassemble the charger and test with a real battery and mains power. ]

Here is my collection of jumpers:










The jumpers appear to be 2.5 mm spacing, but I used the more commonly available 0.1" header pins (2.54 mm spacing). The slight mismatch makes them stay put without falling out. Note: there is black junk over all of the jumpers, in fact over 95% of the PCB, so you need to clean the area around the jumpers. Also, the holes fill up, which is a royal pain. I use a paper clip to push through the holes. You may need to clean the back of the board where the jumpers come through as well. A wooden chopstick, flat at one end and sharpened at the other, is useful for this. I sharpen the pointy end with a pencil sharpener, and the flat end with a small file. (Thanks for the idea, KennyBobby.)

The two jumpers at the left are shorted; the heatshrink is to keep them together and to make them easier and safer to handle.

Here is the location of the jumpers, and some close-ups:










































The power connector on the left of the control board is useful for connecting to ground with a multimeter negative lead or DSO ground lead (though you get tons of glitches when the MOSFETs are firing). I had a plug already made up, but only plugged it into the top pin, so there was no danger of shorting the 15 V power supply. For temporary multimeter negative leads I often use the ground via circled in orange. For +15 V, the top of L1 (in the top left hand corner of the PCB) is handy.

At the output of the driver chips (U15 and U16), you should see ~ 12 V p-p on the low outputs (pin 1), and around 60 V p-p on the high outputs (pin 8). The latter is because you are adding the ~ 48 V from the MOSFETs switching (50 V from the power supply less some diode drops), plus the ~ 12 V from the boost power supply (pin 7, this should be a square wave with the low end around 12 V to around 60 V at the top end, about 12 V higher than the MOSFET outputs).

When all is fixed, you should see some DC output, but not at the actual positive output terminal. This is because the micro doesn't see a battery, and so won't connect the output relay. [ Edit: actually, there is a resistor across the relay, so you should see something at the positive output terminal. ] But there is a spare relay position (only populated for very low voltage chargers whose output exceeds 20 A), where a multimeter positive lead can be conveniently placed:










The negative lead can be placed on the negative output terminal (not interrupted by the relay being open), or the negative output lead if it's still connected.

In my case, I was working on a 288 V nominal unit with a 13:7:8 transformer ratio (many of the transformers seem to have their ratios written on them, particularly the 2 kW units). The :7 and :8 parts add; only the higher two voltage units have this arrangement. Treat it as a 13:15 ratio transformer. Lower voltage chargers will have rations like 13:9 or 25:8. In my case, I expect roughly 15/13 x 50 V = 58 V; I was seeing a little over 60 V.


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## Coulomb (Apr 22, 2009)

I'm fairly confident now what the SOT23 devices marked A1t are: BAW56 high speed dual diodes, available from Newark and no doubt other suppliers. It's confusing because some of them have D designators (as you'd expect from a diode or dual diode), and some have "Q" designators (as you'd expect for a bipolar or MOSFET transistor). Now that I believe I've nutted out the desaturation protection circuit (I'll post that soon), it all falls into place.

One of the diodes I pulled out recently had marking code A1t (no serif on the bottom of the "1", and the "t" looks like a dagger) and what looks like "98" on its side. My replacement has marking code A1W in a similar but not identical "font", and "38" on its side beside it.

The third digit isn't part of the part code; it's a country of manufacture code. "t" just means Malaysia, "W" means China. So I'm pretty confident about the match.

[ Edit: the other parts in the attached list are variations on the same part: different packages, some with more than 2 diodes, and so on. Only the SOT23 variant has the bare "BAW56" type number. ]

[ Edit2: I had speculation at one point that it might be a P-channel MOSFET, but that's now certainly not the case. ]


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## Coulomb (Apr 22, 2009)

Attached is the desaturation schematic for the Elcon/TC chargers, as nearly as I can figure it. Thanks is due to Weber, for giving me the clue that this part of the schematic is probably about desaturation protection. When the lower MOSFETs are on, the 1K resistors (R59 and R63) pull C36 up to one diode drop above the highest MOSFET voltage. When the MOSFETs switch such that the output is high, D5 and/or D6 reverse bias, and C40/43 hold the voltage relatively steady. Q4 on the daughter board (Q4d on the schematic) seems to pull this voltage low during the time that the PWM chip's oscillator thinks it's dead time (upper and lower MOSFETs both off); this is around 200-250 ns. Actual dead time seems to be more like 450 ns, due to delays caused I think mainly by C29/C30 (on the main schematic, not shown in my attachment).

The basic idea seems to be, if the lower MOSFET starts to desaturate (due to over current, for example), then the cathode of D5/D6 starts rising, the anodes rise another diode drop above that, and C36's voltage starts rising. This causes the CS+ PWM chip (U14) input to rise. These chips are designed to current regulate, so as the current sense input rises, the PWM ratio decreases, and the MOSFETs work less hard (hopefully, reducing the desaturation, and saving the MOSFET from catastrophic failure). Obviously, this is not foolproof, as the charger I'm repairing testifies. But this seems to be the intent of this part of the circuit, and hopefully it does prevent blowing up MOSFETs in some circumstances.

I've seen this part of the schematic "hunting". It actually causes an audible screech as the current increases and decreases in a rapid and rather haphazard manner. When I disabled the gate for MOSFET Q3, I found that 2 of every three pulses generated were extremely short ones. I think this was the desaturation circuit in action. As part of drawing this schematic, I noticed that the R12 and R18 gate resistors were high resistance (8K and 13K), way above the nominal 1 ohm. I'm guessing that's actually why Q3 was getting hot. I spent a large part of today replacing U14; until I figured out the desaturation circuit, I figured it must be bad because I was getting the 2 of three pulses short on A OUT but normal square pulses on the B OUT pin. I misread the datasheet, thinking it was saying that the outputs are essentially complementary (it was actually saying that the UC1847 chip has inverted outputs compared to the UC1846 chip, sigh). Replacing the PWM chip (U14) had no effect.

Comments welcome on any corrections to my description.


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## kennybobby (Aug 10, 2012)

Good finding here. i think Paul and i were thrown by the Q designation on the pcb and were trying to make them transistors.

i think we have a unit here that resists repair also--replaced numerous chips and bits which were taken out again on powerup. At least we now know about the jumpers and hopefully how to limit the damage propagation. But it is disheartening when all that hard work goes up in smoke...

Now we understand why the factory guys don't want to touch or repair damaged chargers.


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## Coulomb (Apr 22, 2009)

kennybobby said:


> I think Paul and i were thrown by the Q designation on the pcb and were trying to make them transistors.


Yes, it's strange that half the diodes are designated as Ds, and half as Qs 



> I think we have a unit here that resists repair also--replaced numerous chips and bits which were taken out again on powerup. ... But it is disheartening when all that hard work goes up in smoke...


Absolutely. I believe that this one was one where the use of the current limited power supply and the jumpers saved that heart breaking moment. It's so easy to overlook something.

Now a few notes about *reassembly*. I've noted that you really need to remove both cables (mains input and DC output) to get the PCB out. It turns out it's really helpful at least on reassembly to remove the control cable (to the 7-pin round connector, if supplied) as well. It's a pest to get out, especially to get it completely out, but the following is as far as is needed:










It's still plenty hassle to get it to that stage, but that's enough to get the PCB past easily. If you really wanted to get it out completely, you could probably use a jeweller's flat blade screwdriver to release the metal pins in the plastic socket; you can see the seven slots where you can get access to the piece of metal that holds the pins in place. Mark one end of both the ribbon and plastic shroud to make sure it goes back the right way around.

For the 2 kW chargers only, the PFC inductor is so large that it has its own octagonal heatsink:










[ Edit: The above is too much grease. The octagonal heatsink is used to connect to chassis for safety capacitor C3. I found that after a generous quantity of grease, there was connectivity to the central screw and its nut, but not to the heatsink and C3. Rather than disassemble again, I added an insulated green with yellow stripe wire to a nearby PCB screw. ]

I found this one was still attached to the bottom of the PCB, but had slid away from its original position while still held firmly in place by the thermal paste. I found it well worth taking if off the PCB and placing it on the main chassis. The long threaded rod is acually a very long bolt captured in a slot; it is free to move along this slot. Move it to approximately the right position before attempting to reinstall the PCB.

Speaking of thermal paste, there is a LOT of this stuff in these chargers. If you have a 10 g or 20 g tube of it, it's likely to be a bit short. You might not need as large a tube as I use unless you do a lot of charger repairs, but make sure you have a fair bit available before reassembly.










Finally, the high frequency transformer (large yellow cube with gold anodized aluminum metalwork) has four screws holding it in place, and again these screws are free to move in slots in the chassis. Move the screws to approximately the right position before attempting to reinstall the PCB. The Xs indicate where two screws ended up; obviously, they need to be near either end. The arrow shows the direction and rough length of the slots.










Similar comments apply to the full bridge inductor (next to the 3 position output terminal block). It has one bolt in a slot that should be moved to approximately the right position (nearest the daughter board) before moving the PCB into place. (Two other bolts are inserted from above.) So re-inserting the PCB is a matter of juggling the PCB itself and the 5 or 6 screws (1.5 kW or 2 kW respectively) for the various inductors. Patience is a virtue here.

Addendum: it might be worth checking leakage from AC-in L and N to ground. I had one throw the RCD / GFI on plugging in. It showed 1.3 MΩ to ground when L or N were positive with respect to ground, and a larger than normal capacitance with the opposite polarity. Normal leakage is barely detectable on a typical multimeter, and conduction lasts about a tenth of a second. When I removed the cover to investigate, the problem vanished, and I could not reproduce it. I didn't leave time for the silicone sealant to cure, and the case is fairly airtight, so that might have been the problem. Also one of the very stiff transformer leads would have pushed hard against the cover on reassembly, but I could not measure any leakage on the sleeve.

[ Edit: brass metalwork -> gold anodized aluminum metalwork ]
[ Edit: added addendum. ]


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## Coulomb (Apr 22, 2009)

I also found a piece of single conductor house wire useful for pushing, pulling, and feeling for the bolts that like to ride around in their slots.


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## pdove (Jan 9, 2012)

Speaking of thermal paste, there is a LOT of this stuff in these chargers. If you have a 10 g or 20 g tube of it, it's likely to be a bit short. End quote

It is my opinion that they use too much thermal paste. Correct application is a very thin layer. It's only supposed to fill in the gaps if it squires out the side you are using too much.


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## Coulomb (Apr 22, 2009)

This photo was obtained after much effort: heating and carefully scraping off yellow gunk, while attempting to retain as much as possible of the solder mask, and removing white gunk (silicone) from C38. C2 and C46 are also difficult to remove, both because they are covered in yellow gunk, but also because they connect to non-thermally-relieved pads with thick copper cable reinforcing.










I've updated the schematic to indicate that C46 has the value 220 pF, at least for the charger I was working on. Some chargers seem to have 2 kV rated ceramics, others 1 kV. I guess they just use what is available. C2 always seems to be 2.2 nF (0.0022 uF).

So you can de-solder the capacitors, below shows where they are underneath the board. Note that one end of C46 (north east end in the photo below) is usually under a very heady run of solder and a thick solid wire. There is no connection to the top of the board, and it's close to impossible to suck out the solder from that pad. It's also really awkward to get to, with the call capacitor and control boars so close. So for that pad, it's acceptable to drill through the solder.










Here is where the leads for C46 end up after drilling one pad:











So C38 is my last hope for a failed component that could explain the blow-ups of this charger. The blow-up this time was even more spectacular than last time, with some copper snot ending up on the next MOSFET, giving it a sort of knobby knee 

















As far as I know, the other 2 MOSFETs are still OK, but I'll likely replace them since they've had a hell of a shock, so to speak. I'm part way through removing C2/C46/C38 in this photo.

The Samyoung capacitor has somewhat underwhelming specifications for the main DC bus decoupling capacitor (with C2 doing the very high frequency decoupling). It's rated at 105°C (good), 3000 hr (ordinary, but described as long life), 1.1 A or 1.0 A of ripple current at 120 Hz, to be multiplied by some 1.4x at > 10 kHz (so that's 1.5 to 1.4 A), and it doesn't even seem to have an ESR figure at all!

In another charger I have here, I see an EPCOS B43252 series (105°C, 2000 hr, and 1.42 A @ 120 Hz). Next, a Nippon Chemi-con KMM series (actually a decent capacitor manufacturer), 3000 hr, 105°C, 1.45 A ripple current.

In yet another, a Nichicon (again, good capacitor manufacturer) (L)GL series: 2000 hr, 0.78 A ripple, no ESR rating.

[ Edit: in a charger where at least 2 of the capacitors vented, they used Lelon LSM series (105°C, 1.14 A ripple current, 905 mΩ ESR. All these are 25 x 40 mm form factor.
I have been using a Panasonic EETED2G221JJ capacitor (105°C, 2.03 A @ 50 kHz ripple current, 603 mΩ ESR) replacement, but I see that these are discontinued now. ]

So I'm thinking that C2 must be doing all the hard work with the ripple, and perhaps the other three capacitors in parallel, even though they are in the PFC section, separated from the MOSFETs by the two ~ 100 mm (4") links.

Or maybe I need to get or borrow an ESR meter. Or cobble one together.

[ Edit: the "1" in the top photo is the track that I missed a few days ago, buried under C38 and lots of gunk. Until I figured that this part of the resistor network was connected to something else, I didn't recognize the back to back diodes as D2/D3, or the array of 15 0805 resistors as R33/R4, already there on the original schematic. ]

[ Edit: added under-board photo. ]

[ Edit: added photo of C100/C6. ]


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## pdove (Jan 9, 2012)

I worked on one that failed this way. It blew the mosfet drivers as well and some diodes on the control board.


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## pdove (Jan 9, 2012)

kennybobby said:


> haha funny, ontology = control in this case...schell pecker at work


Thanks I fixed it. Stupid spell checker


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## Coulomb (Apr 22, 2009)

pdove said:


> It blew the mosfet drivers as well and some diodes on the control board.


And did it come good replacing the blown semiconductors and resistors, or did it blow up again? I'm wondering if a lot of these failures are due to capacitor and/or snubber issues - voltage spike / ringing control.


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## pdove (Jan 9, 2012)

Coulomb said:


> And did it come good replacing the blown semiconductors and resistors, or did it blow up again? I'm wondering if a lot of these failures are due to capacitor and/or snubber issues - voltage spike / ringing control.


It blew the driver chips after I repaired the main board. I never tried again.


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## Coulomb (Apr 22, 2009)

Having failed to find anything wrong with the capacitors C38 (large electrolytic), and C2/C46 (small blue ceramic capacitors) in the charger I'm repairing, I've decided to take the advice of a colleague and attempt to separate the gate control signals from the drain/source output signals. Last time we were testing, he detected faint crackling sounds, almost like high voltage arcing over. I thought that could surely not be the case, since arcing would create a fearsome bang. But he suggested that perhaps something was leaking slightly, causing one of the MOSFETs to start conducting when it should not. This is not a problem until the CPU directs the PWM chip to start switching all the MOSFETs; when its companion on the same half-bridge switches on, there is "shoot through" (two transistors conducting from bus+ to bus-), and then the fearsome bang came on cue.

Throughout the charger, there is generally at least 5.08 mm (0.20") pin to pin between any components with high voltage. The MOSFETs are a glaring exception; these are TO-220 devices (so many of them are) with 2.54 mm (0.10") pin to pin spacing. There are thick tracks to the source and drains of the MOSFETs, to reduce inductance and resistive losses. This makes the solder connections bulge somewhat, reducing the gap between for example between drain and gate. It is possible for all sorts of material to bridge that gap - resin from soldering, bits of insulating material (black, white, and yellow gunk), and so on. Dust and moisture can creep across this bridge, allowing an arc to form. The drain jumps from bus- to bus+ in a short time (a microsecond or two I believe) when the upper MOSFET turns on, so even if there isn't much conductance, there can be capacitance coupling the drain to the gate of the bottom MOSFET. All this is encouraging shoot-through.

His suggestion was to cut an air gap between the pins if possible, or stagger the leads a little (so they form a triangle rather than a straight line), or both. It turns out that the former was more possible than I thought, since there is the large cutout in the PCB for the heatsink, but there isn't clearance for the repositioned drain lead.

He also mentioned that I needed to clean off as much of the burned epoxy (now from two sets of blown MOSFETs), as the burned epoxy would presumably contain a lot of carbon, which is of course conductive (in that form). 











The above was taken before I extended some of the slots a bit further. You can see an area at the left where I started to make room for a staggered drain lead, but decided that it would just make the clearance issues worse.

I was also not vigilant last test for scratches in the solder mask:










The yellow circles show areas where the solder resist has been scratched, revealing bare copper. It happens that these are gate leads (marked with a red "G"), near a B+ area (also scratched!) and a drain/source/output track (marked D/S). These also connect to CON32S, the 32-pin connector between the main board and the control (daughter) board. So again, gate signals are routed very near drain/source signals, and I had been removing black gunk from components to read their values and so on. So I'll be using some silicone or the like to protect these areas from creepage before the next test. The scratched solder resist will of course also end up under silicone.

[ Edit: In the above photo, you can just make out the values for C2 and C46: 2.2 nF (marked as 222K) and 220 pF (marked as 221J). These happen to be 1 kV parts; some chargers have 2 kV parts. I think they just use whichever is available. ]

So now I need to replace the MOSFETs again, hopefully for the last time. These holes have no thermal relief, there are heavy copper wires right up close to the MOSFET leads, and the PCB is extra thick to take the weight of all the magnetics (1.8 mm (0.0709", 9/128") instead of the usual 1.6 mm (1/16"). All these factors make it very difficult to remove the solder from the holes, using either a hobbyist solder sucker or solder braid. I don't have access to a proper desoldering station; maybe one day.

I've had success in the past using pins. Pins are usually made of steel with a thin coating that doesn't stick to solder all that well. But the usual household pin is about 0.6 mm diameter. The MOSFET leads are about 0.7 mm across. I tried quilting pins (0.7 mm diameter), hat pins (also 0.7 mm diameter, but lovely and big), and various sizes of safety pins. The safety pin was tolerable, but the coating was adhering to the solder too much, so I had a lot of trouble getting the pin out one it poked through.

In the end, I used ordinary sized paper clips; these are about 0.8 or 0.85 mm diameter. They are cheap enough (and I'm pretty cheap ) to simply cut and discard:










Here you can see the clip has poked through the hole and rotates freely, but a lot of solder has adhered to the clip, making it very hard to remove. So now I merely cut the paper clip with side cutters, and the clip having almost no solder away from the end comes out easily.

In the left of the above photo you can also see R13, which is 1.5 mm x 38 mm of tinned copper wire. This was mentioned recently by KennyBobby; thanks, Ken! Normally this text is hidden under a piece of heat conductive insulating material, and in some cases also under a piece of foam that holds it gently away from the chassis of the charger. That's a 2 kW charger; the layout is slightly different for 1.5 kW models, but the resistor appears to be identical.

[ Edit: middle photo had some tracks mislabeled. ]


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## Coulomb (Apr 22, 2009)

I must be the only schmuck attempting to repair these chargers at the moment. I got all the way to testing with a real battery recently, when I decided to pull the plug before it connected (last time when it turned on the output relay was when the MOSFETs blew again). I did this because I heard the soft cracking sound that my friend (who is kindly loaning the battery, part of his EV pack) thought he heard last time. Last time, I wasn't sure if it was just the input relay doing its normal thing, but this time we both agreed that the crackling sound was back.

He suggested we do a "binary search" for the cause of the sound. We disconnected the battery, since this would allow us to leave it turned in without actually connecting and possibly failing again. Using a piece of tubing as a crude stethoscope, we listened in one half, then the other. We were able to determine that it was on the PFC (mains) side, not the output side, before it stopped happening. My friend thought it might have been coming from the input relay.

I formed a theory about how the DC bus voltage might be too high, so the PFC chip might be shutting down due to over-voltage (there is a divider chain dedicated to this purpose, which seems to trigger at 425 VDC design center). This was aided by me misremembering the DC bus measurement I did at home; I thought it was 460 V. (The bus capacitors are all rated at 400 VDC, so that would be bad long term, not too bad short term.)

But I re-measured, and it's around 392 VDC with either 240 V mains, or with 48 VDC. That's 98% of the 400 V rating of the capacitors, but I believe that they are designed to run at 385 VDC (when running off 220-240 VAC mains), which is over 96% of their rated voltage anyway. The MOSFETs are rated at 550 VDC, so the extra 7 V isn't going to cause the MOSFETs to blow.

I decided to take a closer look at the input relay itself. As you can see, there is a small darkened spot near where the contacts are:










The yellow gunk is from the manufacturer, to keep the tall parts from being affected too badly by vibration. There is also printed circuit lacquer from my having conformal coated the whole PCB. The darkish spot circled in red is hard to see at most angles; that photo happened to capture it pretty well. So is it significant?

This is inside the relay cover:










It's starting to look a bit more serious, but maybe relays always do that.

Here is a closeup of one of the contacts:










You can see that it's taken a bit of a blast at some point. It would have opened under load twice when the MOSFETs blew; there may well have been significant over-current due to the shorted DC bus each time. The input relay always sees AC (unless you run the charger from DC; my testing at 50 VDC was always at quite low current, 2 A maximum). The relay contacts are rated at 250 VAC and 16 A, or 30 VDC and 16 A.

Any opinions on whether the contacts are seriously damaged? They seem to measure low resistance and with a reliable connection, as judged by a cheap multimeter on the beeping continuity setting. (I have a Fluke that removes the "scratchy" sound you get from cheap multimeters when lightly rubbing the probes together; in this instance, this feature is unwanted).

In particular, should I carefully and lightly sand the contacts with very fine sandpaper? This could remove some of the blackness, but may also remove some of the miracle coating that the contacts may have.

The input relay is an Omron G2R-1-E with 12VDC coil.

The way to remove the relay cover (after removing as much as possible of the yellow gunk) seems to be to grasp it firmly with a large pair of pliers. This has the effect of making it bulge slightly, which releases the two clips at the bottom (which are difficult to reach due to the tall components nearby). I suggest replacing the yellow gunk with silicone when all is done.


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## weber (Apr 22, 2009)

I'm the friend Coulomb mentions in the previous post. Well spotted, Coulomb. I can well believe that subtle arcing of that burned contact when closed, could have been the source of the sound I heard. 

I remind you that, although the sound went away suddenly while we were still trying to narrow it down, that relay was in the quadrant that we'd narrowed it to, and when I listened right at the relay (and only there) I could hear a very quiet sound that was of the same character as the louder crackly sound we had both heard.

I suggest you get your daughter (with younger ears having better high frequency response) to have a listen to that sound, through a plastic-tubing "stethoscope", assuming it's still there. Then either clean the contacts, or better-still, replace the relay, then ask her if the sound is still there.

I was previously thinking it was the relay _coil_ acting as a speaker for a noisy power supply, but the idea that it is the contacts, has the benefit of a ready explanation of why it suddenly went much quieter, i.e. making better contact by semi-welding itself.

However, I have no idea how a noisy 240 Vac relay contact could possibly lead to MOSFETs blowing up. As you suggest, it might well be a _result_ of the blowups rather than a cause of them.


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## kennybobby (Aug 10, 2012)

Howdy Mike, i'm busy with OEM bms cards right now, but crackling sounds from AC relays is not good. i use ultra fine paper for polishing metal, aka crocus cloth, for cleaning relay contacts.

AC has a way of eroding metal. In a sliding contact only the highest spots of the surface make connection and carry the current. When the current exceeds the point-contact thermal limit then a micro-fusing event occurs which vaporizes the metal and transfers the connection to the next highest spot on the face. Over time this erodes and discolors the contact surface and is the likely source of the crackling. If the contacts are held open by a small charred residue or debris from the fusing, then the ac will arc across in order to keep current flowing. This micro-arcing also erodes the surface and makes a crackling sound. On motorcycle regulator/rectifier boxes this occurs at the spade lug terminals from the alternator and usually melts/burns/chars the plastic connector housing--lots of fun to fix those too... cheers mate, kenny


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## pdove (Jan 9, 2012)

Just as a note I replaced these relays on several of the units I fixed because they were charred.


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## Coulomb (Apr 22, 2009)

weber said:


> I remind you that, although the sound went away suddenly while we were still trying to narrow it down, that relay was in the quadrant that we'd narrowed it to, and when I listened right at the relay (and only there) I could hear a very quiet sound that was of the same character as the louder crackly sound we had both heard.


Well, it turns out that the sound was not from the relay at all (contacts or coil), but from the 2.2 uF capacitor right next to it. It is best heard through a tube "stethoscope" aimed right at the middle of the largest face of the capacitor. This was vastly easier with the capacitor soldered under the PCB:










When we removed the old capacitor, we wondered about the discoloration in the white gunk (as opposed to the yellow gunk and the black gunk! ) under the capacitor:










But we decided that this wasn't a contributing factor.

There is another of these 2.2 uF MKP polypropylene capacitors across the mains input. We swapped the two capacitors, and found that the other capacitor made the same soft sound: a faint crackling. We left the charger running for an hour or two, and did not notice the louder version of the crackling. So the louder crackling seems to be an intermittent feature of the original PFC capacitor (the one between the relay and the bridge rectifier).

I ordered new Epcos replacements (now owned by TDK), and soldered them in place. I now could not hear any sound, but was this because it was so hard to get to the large face where the soft sound was coming from? I thought to solder one of the new ones underneath the PCB, but then it might be different because I had the new capacitor in place already. Removing the capacitors and especially cleaning the holes of solder is a considerable pain. So I soldered the *old* capacitor under the PCB first. I could hear a faint crackling, but it seemed much fainter than at Weber's place, where there wasn't a new capacitor soldered across it. Now I replaced it with a new capacitor under the PCB (still with the other new one on the top of the PCB), and found that the new capacitor also made the same faint crackling sound.

So these capacitor seem to be slightly acoustically active. I tried searching for this, and found that some ceramic capacitors act a bit like piezo electric sounders, and that there are ways of circumventing this problem. Of course, I found lots of pages about amplifiers causing crackling *through the speakers*, but that doesn't seem to be relevant.

Anyone else come across acoustically noisy capacitors before? (Apart from ones that have failed and oozed goo or the like, of course.)

Edit: Just to be clear, my tentative conclusion is that the faint crackling seems to be normal, though some brands or models may be noisier than others. The intermittent, louder crackling that could clearly be heard without the stethoscope, seems to be abnormal, and I hate to think what is happening when it comes on.

Edit 2: The more I think about it, the more I think that there wasn't anything wrong with the original capacitors, and that the intermittent loud crackling is due to intermittent behavior of the PFC stage. I wonder if it coincides with control tones on the mains, or if the PFC stage intermittently just goes mad. If the latter, it might explain the MOSFETs blowing up, through a higher than normal DC bus voltage.


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## Coulomb (Apr 22, 2009)

It's possibly obvious, but since it just happened to me, I thought I'd point out a problem that can happen when reassembling the heat-sink clips:










If you managed to leave it in this condition, the heat-sink clip would short out all the MOSFET drain connections. This is considered harmful 

The clip needs to end up on the black epoxy of the MOSFETs.


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## kennybobby (Aug 10, 2012)

i want to find some caps like that to test whether they will sing for me...


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## pdove (Jan 9, 2012)

Coulomb said:


> It's possibly obvious, but since it just happened to me, I thought I'd point out a problem that can happen when reassembling the heat-sink clips:
> 
> 
> 
> ...


Oh crap! I never considered someone making that mistake or the implications of clipping them together. I noticed when I took them apart that the clip went on the plastic black part of the MOSFET's but I wasn't thinking this would connect the drains.

Did it blow up on you?


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## pdove (Jan 9, 2012)

kennybobby said:


> i want to find some caps like that to test whether they will sing for me...


We still have 2 defunct chargers to play with


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## Coulomb (Apr 22, 2009)

pdove said:


> Did it blow up on you?


No, this was before I tightened down the screw, and fortunately I noticed it. Usually, there is little to no gap between the heat-sink clip and the heat-sink "wall", but this time there was about 1/8" (3 mm).

If I hadn't noticed, I might have screwed down the heatsink, which might have forced the MOSFETs down, possibly buckling their leads. The heat-sink clips obscure everything from above, so even this amount of mangling might go unnoticed to someone less familiar with these chargers. Hence the post.


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## Coulomb (Apr 22, 2009)

I'm at Weber's house testing the repaired charger (so far so good).

But before charging, we decided to check for crackling sounds (using his far superior ears). Yes, the new after-bridge capacitor was making a very similar sound to what the original capacitor was, when it wasn't being very noisy.

But before that, at first switch-on, he yelled to turn off the power, he saw a puff of smoke! Arrgh - what now? All I had done since last test was to change the capacitors and also the relay. Oh wait - to get to the relay I removed the pre-charge resistors, and part of the pre-charge resistor always seems to come away with the yellow gunk. So I replaced them with new ones. New wire-wound ones, because I could never understand why the manufacturer stuck with carbon composition types* that burned up so badly whenever the power supply failed (often due to other failures). We suspected the new resistors, so we powered up again and noticed a puff of smoke from the resistors, but it didn't continue. Obviously, when the relay turns on, the pre-charge resistors are shorted, so they then dissipate no power. Sure enough, every time we started the charger, they would emit a little puff of smoke, but otherwise appear to be OK.

I then realized that each resistor is seeing the full 240 V at start-up, so that's initially a power of E^2/R = 240x240/150 = 384 W. Wow, that's a big overload for a 2 W resistor, just for a short period of time. Maybe the originals were 3 W or 4 W, but even so, it's obvious that high peak power types are required there. Ordinary wire-wound resistors are never going to achieve that.

Maybe the resistors can handle it; they seem to have the same resistance after a half dozen starts. But it seems like a bad idea.

I'm not sure what to replace them with. Perhaps two 5 W high pulse power resistors (these are wire wound, but with epoxy and a heat-sink). Or carbon composition resistors with a slow-blow fuse in series (say a 1 A 20x5 type). But it would take a lot of trial and error to get the fuse rating right, not causing nuisance blowing and yet still protecting against massive overload. Maybe a thermal fuse would be better than an electrical (current based) fuse.

* Edit: see post after next; it seems they aren't carbon composition types as I had guessed. Also, it seems that some wire-wound resistors are good at high pulse power too.


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## pdove (Jan 9, 2012)

Yes, kennybobby and I did that calculation on the first couple we repaired. They all had these resistors burnt to a crisp. We puzzled over a way to power up the viper before the relay closes instead of going through these resistors but we never tried anything. It's a very common failure since any problem with the viper power and that relay opens and they get full power. Maybe they are meant to fuse but seems like the wrong component for that.


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## Coulomb (Apr 22, 2009)

Coulomb said:


> ... I could never understand why the manufacturer stuck with carbon composition types that burned up so badly whenever ...


It seems that my guess was wrong. Here is one of the original 150R pre-charge resistors split apart with a chisel:










I should have realized that they weren't carbon composition by the end caps**. The white material in the middle is totally non conducting, likely ceramic. You can see the spiral grooves that they use to trim the resistance of metal or carbon film resistors. By the dark color, and the smell when they burn up, I'd guess they are carbon film types, but I would not know.

So I think that the original pre-charge resistors aren't particularly specially chosen for their pulse power rating; perhaps they merely use coatings and paint that can tolerate the high temperature extremes from a pulse of power.

[ Edit: after a little reading, I think they may be metal oxide film resistors, which are good but not the best for high pulse power. ]

[ ** Edit 2: It seems that some composition resistor types also have end caps, especially ceramic composition types. So that's not the way to rule in or out whether a resistor is a composition type or not. ]


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## pdove (Jan 9, 2012)

That's good to know. I still think a fuse or some type of protection is needed there for when the relay fails to close to keep them from frying. Or another way to let the viper come up to full voltage before closing the input relay.


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## Coulomb (Apr 22, 2009)

I finally settled on these replacements:

http://www.digikey.com/product-detail/en/ohmite/OX151KE/OX151KE-ND/823910










They're only 1 W continuous power, but that's because they're ceramic composition types (more or less the modern equivalent of carbon composition resistors), which use the whole body as the resistance. So they can't get rid of the heat from inside the core of the resistor as well, but that makes them ideal for absorbing energy pulses. At 250 V, the resistors need to absorb 50 J between them, and these can do 50 J per resistor. They are also the same color and about the same size as the originals; the only difference is the 10% tolerance compared to the originals at 5%. But exact resistance value is not important, as far as I can tell.

They're about 100x as expensive as the wire-wound types, but still only a few dollars for a single charger repair.

But I don't know what they are like for overload. They could well hang on for dear life. So I might investigate some thermal fuses as well. Ah, they could replace the longer leads of the pre-charge resistors, like the attachment.

The middle pads, which normally take the longer leads from the resistors, connect together. All three components could be siliconed into a blob for mechanical strength, insulation, and thermal connectivity.


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## Caps18 (Jun 8, 2008)

Is there some way to test what voltage my charger is set to prior to attaching a battery? I haven't hook up a computer to it yet, but I'm thinking it will say the same thing my multimeter did. It was 0.24V or something close to that at the Anderson connector. If I hook up the computer can it be set there?

I will have to do a lot more reading on setting this up and the right way to charge these batteries.


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## pdove (Jan 9, 2012)

Caps18 said:


> Is there some way to test what voltage my charger is set to prior to attaching a battery? I haven't hook up a computer to it yet, but I'm thinking it will say the same thing my multimeter did. It was 0.24V or something close to that at the Anderson connector. If I hook up the computer can it be set there?
> 
> I will have to do a lot more reading on setting this up and the right way to charge these batteries.


I assume you have an Elcon / TCCH charger as they are called sometimes. 

There is usually a label on the side that has 10 curves to choose from like this:

The unit will flash the led the number of times to tell you the curve its using. To change it you hold down the button when powering up till it flashes the number for the curve you want then let go of the button.


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## Coulomb (Apr 22, 2009)

Caps18 said:


> Is there some way to test what voltage my charger is set to prior to attaching a battery?


Occasionally, there won't be a list of settings on the side. If so, there is unfortunately no easy way to tell what it will do. 99% of the time, you will get a clue about either the nominal or the absolute maximum voltage the charger will put out from a separate label.

If you have the programming hardware per this post, then you might be lucky and not have the security bits set, so you can read the firmware. Someone like myself can tell you what the settings are from that. You don't need to open the charger for this, just remove a label.

If you have no idea what voltage level the charger is set for, you could open it up and hope that they have marked the high frequency transformer with the *nominal* voltage of the charger. For example, it might be marked "120 V" or "288 V 13:7:8". The former would be nominally 120 V, able to charge up to about 168 V. The latter will go to about 389 V; see the TC or Elcon charger web site for details. The transformer seems to be marked about 95% of the time.

Edit: there is also the chance that it's a CAN bus version. In that case, the voltage and current are set externally.CAN bus models will have a small "dongle" to convert serial signals to CAN bus and back again.


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## Coulomb (Apr 22, 2009)

It seems I never posted about the *measurements possible without removing the PCB*. I'll place them here.

It's hard to jam a multimeter probe at the bridge leads, at least while the heat-sink clamp is in place. Fortunately, the line end is accessible through the junction of the two long ends of the pre-charge resistors. So to measure the value of the pre-charge resistors, you can measure between there and the line input. This includes the resistance of two line chokes, but their resistance is negligible. It should measure 75 ohms, give or take about 10%.

Positive output from the bridge rectifier is easy to get to; it's the pin that's a larger distance from the others, towards the edge of the board, and accessible via a large pad.

Negative output from the bridge is essentially "GND"; there is a marked pad (it might be under some yellow gunk), and it also makes it to the output side of the board via the top side red jumper. 
[ Edit: on the 2 kW chargers with three capacitors on the mains side, it is in about the same position relative to the large PFC inductor. In other words, the extra capacitor is nearer the yellow power supply transformer and power supply chip with the small copper heatsink. ]

The other AC input lead to the bridge rectifier connects essentially to the Neutral input.

So now the four pins of the bridge rectifier are accessible: L and N are the AC inputs, (the 75 Ω pre-charge resistors won't affect diode measurements much), negative output is "GND", and the positive output can be accessed by the large pad.

[ Edit: the positive output of the PFC stage, the "DC bus", is easiest to get to near the big capacitor on its own, where there are several vias, as shown. ]

2018/April: Finally, more of an observation than a measurement. If the processor is flashing its small red LED or the red/green LED, then you know that the 12 V power supply is working. If the input relay pulls in, then you know that the 15 V power supply is working (presuming non-welded contacts). Both of these tests can be done with a ~52 VDC power supply applied to the mains input.

[ Edit: Forgot to add the images; added comment re 2 kW chargers; easier access to DC bus plus; added comment re pre-charge resistors not affecting bridge diode measurements ]


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## Coulomb (Apr 22, 2009)

Now some *repairs possible without removing the PCB*. This one is replacing the 150 ohm pre-charge resistors, which often get burned up through various mishaps. In my case, I needed to replace the wire-wound resistors (from a previous repair, actually just getting clearance to replace the input relay) with ceramic composition types, because the wire-wound types were emitting a little puff of smoke with each switch-on of the charger. During the first 100 ms or so, these resistors are required to take up to 50 Joules between them, with a peak pulse power of nearly 200 W each.

I also wanted to try adding a slow-blow fuse, as posted recently. Back then I suggested a thermal fuse, but a slow-blow fuse of suitable rating should be about as good. I chose a 750 mA part; it seemed to be a good compromise between not nuisance blowing with the large surge of current, and blowing in 10 seconds or so if the resistors end up across the mains.

You can see the before and after photos in the attachments. I did the whole repair from above the PCB, but I found that after it was done, the fuse no longer connected to the bridge rectifier. So I was forced to take the PCB off after all  It turns out I damaged the pad under the fuse. It looks like it would have been better to use the hole that is slightly further away from the edge (i.e. the one for R1, not the one for R23). It has a reasonable sized track attached to it, so it may survive the rigors of clearing solder from the pads better than the other pad. (Both middle pads connect to the same place; there is a small sliver of track between the two middle pads.)

You can also see one of the hassles of repairing from above the board: the shiny plastic gets in the way, and it's nearly impossible to avoid burning it with the soldering iron. (Hence the hole burned in it.)

Edit: the ceramic composition resistors seem to work well. With each switch on from 240 VAC, there is about a 5°C temperature rise, which dissipates over a minute or two. The 750 mA slow blow fuse also seems suitable, but really only time will tell if it will nuisance blow too soon.


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## Coulomb (Apr 22, 2009)

I struggled to replace a transformer today. I remembered the solution was something to do with very small pieces of Blu-Tack, but I was trying to place the nyloc nut with pliers. Eventually it came to me that you use a Philips screwdriver to place the nut, and attach the nyloc nut to the end of it with the Blu-Tack, as attached. You position the nut over the bolt, using another screwdriver to bend the bolt to a suitable position if necessary. The idea is to use the temporary connection of the Philips screwdriver to the nut to get half to one turn of thread on the bolt before the Blu-Tack gives way. Remove the screwdriver(s) and use a long nosed socket to complete the job (many, many turns). Repeat as necessary, but I find that this works pretty well first time almost every time.

[ Edit: Ok, the really hard one under the transformer cables may take a few goes  ]

Using a Philips screwdriver to get the first half turn on the bolt or stud works well for all the nuts, not just the transformer bolts. Usually, the Blu-Tack won't be needed for the other cases; you can usually position the nut by finger or pliers, just balancing on the bolt or stud, but the half turn from the Philips screwdriver gives it a lot more stability for when you apply the long nosed socket.


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## ErvB (May 13, 2016)

Coulomb ~ Thanks to all of you for your info regarding these chargers. I have a 6kw unit that had been doing a great job for the last year or more until it stopped in the middle of a charge... at work. I located and read through the posts for these and have gleaned tons of good info. Mine displayed the red/green alternate flash that indicated loss of communication. I disconnected my charge enable circuit and measured for signal voltage and it was good. I connected my test plug that eliminates my charger interrupt circuit ~ no difference. I pulled the cover and checked the communication circuit that daisy chains from each charger and all seemed to be solidly attached. I started checking the output fuses and found the final charger in the series of three had a blown fuse. Not only was it blown but while I was removing the shrink wrap from it I could feel it give a little at the solder point under the fuse body. Turns out that it had a cold solder joint. Getting to it was a pain but at least it was in the front of the board so removing all of the tiny nylock nuts and gently wedging the board up for clearance I was able to get a solder iron in there without melting everything else. It works! I have a question for the forum: my charger appears to be three 2k chargers in the box. If this last section were to fail, is it possible to eliminate it and use the two remaining for a 4k charger? What would that take to accomplish? I don't know if this is the correct place to post this. If not, please direct me and I will make it right. Thanks for sharing all of your experiences/info with the rest of us! ~ Erv


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## Coulomb (Apr 22, 2009)

ErvB said:


> Coulomb ~ Thanks to all of you for your info regarding these chargers.


I'm just reporting some things I've noticed. Glad it was of practical value to someone.



> It works!






> I have a question for the forum: my charger appears to be three 2k chargers in the box. If this last section were to fail, is it possible to eliminate it and use the two remaining for a 4k charger? What would that take to accomplish? I don't know if this is the correct place to post this.


The last one must have been the master. With a triple charger, there would be one master and two slaves. I haven't looked at that part of the code for a while, but from memory, the master knows how many total chargers there should be, so for example it divides the total current by 3 if there should be 3. So you'd have to change that constant to 2 for a 4 kW (2 x 2 kW units) charger. So I guess this belongs on the Firmware discussion thread:
http://www.diyelectriccar.com/forums/showthread.php/elcon-tc-charger-firmware-discussion-134233.html

Now that I think about it, the difference may be in the EEPROM, not the main flash code. Of course, if it is your master that died, then one of the slaves would have to turn into a master.

The short answer is: it can be done, but it would be a fair bit of work.
http://www.diyelectriccar.com/forums/showthread.php/elcon-tc-charger-firmware-discussion-134233.html


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## ErvB (May 13, 2016)

Thanks for the info. I will take the charger 6k to 4k question to the thread referenced. Hopefully I wont have to do the reduction but it seems prudent to understand the process. Thanks again for all of the knowledge/experience shared on these chargers!


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## Coulomb (Apr 22, 2009)

I've just started a repair, and it's unusual enough to warrant a few photos, I think. The first clue was the not-quite-burning-resistor smell as I took off the lid. (I know the customer had already had a look inside, so the source must be strong.) Inside the lid was an odd oily condensation; I still have no idea why it stops abruptly along the left side [ Edit: it was just the way the customer took off the lid; sliding along the rubber seal for that distance ] :










Next was the capacitor that seems to have lost the top part of its plastic sleeve:










The other capacitors that size (they are all in parallel) have a black top, not a silver one. I wonder why that is? But then I spotted this:










I'm guessing that when I get the PCB off (this takes half an hour), there will be gunk from the other end of the capacitor. The customer said the charger sizzled when operating; I'd say it's capacitor electrolyte bubbling out of the lower end, possibly causing arcing.

[ Edit: the circular black thing on the back of the vertical control PCB (circled in yellow) is the top (or perhaps bottom) of the capacitor, held on by surface tension from the oily gunk from inside the capacitor. This capacitor must have failed and exploded off its ends. This capacitor absorbs/provides the spikes of current as the MOSFETs switch, so they work hard. I've not seen one fail like that before. ]


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## pdove (Jan 9, 2012)

Weird. They usually burst the vent cuts on top.

The capacitor cans are sealed at the bottom with a bung. This is usually made of a synthetic rubber called EPT or Ethylene-Propylene Terpolymer. In low quality capacitors it can be made of natural rubber which shrinks with age. Also the seal may simply not be strong due to the manufacture of the capacitor. 

So what can happen is that instead of the gas and electrolyte being released at the top of the capacitor via the vents, the capacitor instead pushes the bung out somewhat and leaks electrolyte on the board.

Be sure and clean all the electrolyte off the board with alcohol because it can be corrosive.


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## Coulomb (Apr 22, 2009)

A photo with C7 removed (C7 is one of the three main filter capacitors on the AC side of a 2 kW model charger):










It was quite a hassle getting the two capacitors off the main board. Of course, the yellow gunk and most of the white gunk holding the capacitors in place had to be removed, while as much as possible not scratching the solder mask of the PCB. It's also good to avoid overheating adjacent parts.

Prodigious amounts of solder are used on these capacitors; I ended up using two soldering irons, both with large tips. In the end, pushing and pulling on the capacitors to wiggle them out a millimeter or two each time won the day.


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## WolfTronix (Feb 8, 2016)

You need a "Big Bertha" Soldering Iron, makes quick work of any large part on a power plane:


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## pdove (Jan 9, 2012)

How many watts is that thing? 200W?


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## Coulomb (Apr 22, 2009)

The charger with the capacitor problems worked fine on the bench when the capacitors were replaced. The small caps C2 and C46 seemed to be fine, but I replaced them anyway.

However, when tested with an actual battery, there was a horrible arcing sound. I quickly disconnected and decided there must have been something obvious that I had overlooked.

But try as I might, I could not get the charger to play up on the bench. It's a 168 V 15 A model, so I assumed it would need at least half the nominal 144 V on the battery terminals for it to actually charge a battery. I was pleasantly surprised to see that this CAN model (or one very like it) has a minimum battery voltage of under 20 V. So today I tested it on my solar 50 V battery. After some hours of frustration due to the recent "thanks, Microsoft" Windows 10 update (I suspect that many of you know exactly what I mean by that*), I used an older Windows XP laptop and was able to communicate. The arcing sound was there all right, and it sounded like it was coming from the output relay.

[ * Edit: turns out it was loser error (my own fault). I have two Prolific adapters, one marked "old", and I didn't notice I had the old (Rev 0300) one. Needless to say, it's marked much more explicitly now. ]

Well, I suppose that's the only part you don't get to test on the bench without a real battery; the output relay itself. Back on my bench (the solar battery is outside, not accessible from the bench), I forced the relay closed with a clip lead. It gave a nice click, but there was no conductivity across the contacts. A faulty relay! Strange.

I don't have those relays in stock, so I ordered a pair from RS Components. After removing the PCB (what a job), I prepared to desolder the old relay, hoping to see what was wrong with it. That made me look closely at the solder joint for the contacts; one of them was looking decidedly bad:










I know what a pain it is to remove those relays, so I tried soldering the joint properly. Now when I force the relay closed, I get zero volts across the contacts. So the relay is possibly fine inside. It may have been a marginal solder joint, that got got with use, and gradually let go. It doesn't seem to have anything to do with the capacitor fault, unless the heat of the arcing accelerated the capacitor failures.

I'll have to wait till I get time to test it out on the 50 V battery again, but I suspect I've fixed it, and now have two spare relays on the way.

Update: it seems to work fine.


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## kennybobby (Aug 10, 2012)

Good catch on the relay. That is an awful looking solder joint--like there was never any bonding at all. Too much oxide on the lead, not enough or wrong flux, didn't put heat on the lead during soldering, etc. It's a wonder it ever worked.

Feel your pain on micro$loft...


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## Coulomb (Apr 22, 2009)

pdove said:


> Every Charger I have opened has Black going to Neutral and White going to hot or Load as labeled on the PCB. As you stated, this is backwards for US wiring.


Most of my chargers come from electric cars, which have the charger wired in. So the Chinese mains wiring is usually long gone.

However, the latest one has an IEC C14 connector, with L, N, and E clearly marked. (The labels are correct, too, when fitted to an Australian molded cord with a C13 connector at the end.) I found that the active was indeed black. I'm 90% sure that it was wired to the lug marked N. So these chargers do indeed appear to be wired with line and neutral swapped.

It doesn't make a great deal of difference, as long as the AC fuse doesn't blow. But it's disappointing. What other safety related standards are they ignoring?


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## Coulomb (Apr 22, 2009)

... Continued from the schematic thread here.



crackerjackz said:


> this thing is sealed pretty well when i opened it up only a few ml came out and the only traces i could see were on the horizontal control board specifically were the little button is to change programs ....


I see severe rust on the nut at the left of the sixth photo (first one with fingers in it), and white marks that suggest water residue to me.

Water and non-extra-low voltage don't play well together, so you may have a lot of trouble with this one. You seem to have an extra hole with an empty (?) cable gland near the mains cord entry... is that open to the outside? Surely a lot of water could have gotten in there if so.

I also see slight browning of the yellow gunk near the 150 ohm pre-charge resistors. It's probably nothing, but worth checking them for high resistance. It's one of the few checks you can make without taking off the main PCB. I have notes on this in this thread here. (See also some relevant posts several posts before that one.)


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## PStechPaul (May 1, 2012)

I'm not yet ready to finish the EMW charger repair/upgrade project, and I already have two chargers to work on. I've had other things take my interest and priorities, but it is still something I hope to finish. I'll post my progress in the relevant thread. Ideally, it will not require shipping the entire charger to me. It should just involve replacing the control and driver boards, and changing some connections to the main power board. I feel bad about not making more progress in the past year or so I've had them, but my intentions are good. I have always had problems "finishing things".


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## crackerjackz (Jun 26, 2009)

You are not the problem or issue paul lol .... valery and his half finished / modified incomplete schematics and instructions are :s ... i just so badly regret having bought from emw  


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## Coulomb (Apr 22, 2009)

When finishing a charger, it's best to test through the 7-pin round connector, especially if it's a CAN model or the 7-pin round connector is otherwise used.

I had an issue where a charger 7-pin round connector had twisted such that the wrong pins from the plug mated with the pins of the socket. I find I need a lot of force getting the socket undone and re-tightened, never dreaming that this force could mis-align the socket internally.

Details along with a photo here:

http://forums.aeva.asn.au/forums/fo...63203&title=tc-elcon-charger-connectors#63203

Edit: I wonder how many repaired chargers go back together, to fail at the very last hurdle like that.


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## crackerjackz (Jun 26, 2009)

Thanks definately worth me checking this properly tommorow  ... 


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## crackerjackz (Jun 26, 2009)

Any help appreciated  ive made some progress









I get 260 volts dc on my two red wires under the board when i put 120 volts on the input of the charger .... 

I grt 12 volts dc on the a1-a2 pins of the relay so i know my power board power supply is working ..., 

My issue is with the control board power supply









Nothing on the tiny +~ signs at the bottom of the control board ... when i apply an external power supply to these empty pinouts my charger turns on and lights start flashing ect then lights just stay green which is normal .... since my batteries are disconnected and my bms enable is open




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## crackerjackz (Jun 26, 2009)

How do you guys get rid of the black gunk to protect the chips ??? Im trying to locate a 117m3 chip but when i use my nail scratch the black gunk off i cant read the chips or hardly anymore ... 


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## crackerjackz (Jun 26, 2009)

There are two ir2110s chips on the control board respectively called u15 and u16 .... one should be at 12 volts dc and the other 15 volts from my understanding ... i cant seem to find a good ground reference so im using the ground from each opposite chip to avoid shorting ... when i do this i get 15 volts dc at both ??? Shouldnt one or the other be lower ?










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## duranza (Aug 27, 2009)

crackerjackz said:


> There are two ir2110s chips on the control board respectively called u15 and u16 .... one should be at 12 volts dc and the other 15 volts from my understanding ... i cant seem to find a good ground reference so im using the ground from each opposite chip to avoid shorting ... when i do this i get 15 volts dc at both ??? Shouldnt one or the other be lower ?
> 
> 
> 
> ...


My elcon doesn't have the black stuff on it. I will take a picture of the board with the numbers on it when I get home tonight.


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## kennybobby (Aug 10, 2012)

You have the high voltage so at least half the main board is working, the other half requires the control board working to boost and regulate the output. The 12V to close the mains relay is the same 12V to the control board pins1 (+) and pin 16/17(-), so check those to see that 12V is going to the board.

i used a bamboo chopstick in which i made a point on one end in a pencil sharpener, and made a flat blade like a screwdriver at the other end using a pocket knife. This will lift and push the black sealer away and not damage anything.

If you have 12 V to the control board but no power on the board then maybe the filter inductor, L1 on the control board schematic, has fused open. i think it is a surface mount device in the upper left corner of the control board looking at the component side with pin 1 at the far left.


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## crackerjackz (Jun 26, 2009)

From the drawings im pretty sure i saw 3 power supplies ... one on the control board .... one auxilary 15 volt on the left side of the control board and an isolated 12 volt power supply on the right side of the control board .... please do correct me if im wrong :O .... 


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## Coulomb (Apr 22, 2009)

crackerjackz said:


> From the drawings im pretty sure i saw 3 power supplies ...


No, just the two. [ Edit: well, there's the 3.3 V bus, called +VCC on out schematic, but it's derived from the 12 V "isolated" power supply, and has the same reference (DGND on our schematic) as the 12-13 V power supply; see below. ]

The first, about 15 V, powers everything before the HF transformer (PFC stage, the power supply chip itself, the UC3846 (U14) and its two drivers (U15 and U16; Vdd on these (pin 11) are connected together), the PFC chip U2, quad comparator U13. The reference for these is called GND on our reverse engineered schematic (thanks, guys!). It's on two pins of a white connector at the very left edge of the control PCB; I often plug something in there with a clip lead for a multimeter or a DSO (NOTE: I only use the DSO when running from an isolated power supply, not the utility mains).

The second, some 12-13 V, runs everything after the HF transformer, which is mainly the processor U5, current shunt amplifier U6, and anything connected to the 7-pin round connector. The reference for this can be pin 2 of the 7-pin round connector, the 5-pin programming port marked GND (not to be confused with the reference for the other power supply). It's called DGND on our schematic. You have a rev 8 control board; rev 7 and earlier don't have the + and - pads (I assume that these connect to the input of U3, the 3V3 regulator (SPX1117M3).

I have seen diodes and inductors blow in the 12 V path, so check D13 and L11 on the main board. [ Edit: In addition to L1 on the control board, as KennyBobby suggested. ] I don't believe that the value of L11 is critical; I replaced one with a 100 uH inductor of approximately the right size from a local electronics supplier. It doesn't have to supply much current, mainly the output relay, so any size other then the smallest you can find will probably do.

Usually, the reason that the inductor or diode in the 12 V path blows is because of pack voltage ending up on it or the 3V3 bus, and that usually blows the processor and a lot of other parts. You seem to have been lucky, since your processor seems to run fine. I don't see a need to replace U3 (the 3.3 V voltage regulator), if you applied 12 V to get the processor working. (If you supplied 3V3 to the 3V3 side, then that's different).

Sounds like you're not far off a successful repair.


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## crackerjackz (Jun 26, 2009)

Thanks ... you obviously know your stuff 300 times more than me so its gonna take me a few days to assimilate and test it all lol ... what im sure is that all i powered is 12 volt to the right side of the control board and everything started up . So ill definetly look into the points you mentioned . Thanks 


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## Coulomb (Apr 22, 2009)

kennybobby said:


> The 12V to close the mains relay is the same 12V to the control board pins1 (+) and pin 5(-)...


Strictly speaking, pin 5 isn't power GND, it's the other side of a shunt for the PFC chip (R13). Unless you're drawing a lot of current, the difference should only be millivolts.

Perhaps we should call pins 16 and 17 the reference for the 15 V power supply (called 12VDC_Aux or +12_VDC_PS on our schematic), since these are marked PGND, and you can aim on the pin 17 side of pin 16, so if your probe slips, there isn't any harm done. This is all on my amended version of the control board schematic.


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## kennybobby (Aug 10, 2012)

i edited to change from pin 5 to the pin 16/17 for (-) on the aux 12V.

From your test it sounds like you may not have the 'isolated' 12V supply to the right end of the control board (the 3.3V comes off of the isolated 12 also) so i would look at the low voltage SMPS schematic and trace the ViPer, like Coulomb said it could be one of the large diodes or inductors opened up.


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## Angelito (Jul 5, 2013)

I have just received my TC 1.5 kw charger. When I installed the charger, I unfortunately got the old diagram whch required the application of 12 volts external power to the thin black and red wires.. Based on my readings, what i am supposed to do is to just short the two wires (red and black) since mine is a new version and it has an internal low voltage source... Will the damage to my charger be substantial? thank you in advance for your answer..


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## Angelito (Jul 5, 2013)

My charger does not have the multi pins, just the red and black thin wires...


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## crackerjackz (Jun 26, 2009)

Pics ???? You dont mention anywhere if it still works or not ? What happens if you plug it in ? 


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## Coulomb (Apr 22, 2009)

Angelito said:


> I have just received my TC 1.5 kw charger. When I installed the charger, I unfortunately got the old diagram which required the application of 12 volts external power to the thin black and red wires..


Err, no. 11-13 V is *supplied* on two of the three pins. But no matter, that's not what you have now.



> Based on my readings, what i am supposed to do is to just short the two wires (red and black) since mine is a new version and it has an internal low voltage source... Will the damage to my charger be substantial?


The documentation on the TCCharger web site seems to be badly lagging; they don't even say that a HQ model (I'm assuming that's what you have) exists at the 1.5 kW level, let alone EV voltage levels.

My best guess is that you have this: [ Edit: I've changed my mind; I think it can't be a HQ model, just a standard TCCH model with only two wires of the 7-pin round connector brought out. See later posts. ]










From http://www.tccharger.com/english/Product/T36/55.html, which is for a 2 kW HQ charger, which apparently look like this:










If so, then one of the wires goes through a 5K1Ω resistor, so no great harm should have been done. I'm assuming that your 12 V source had no connection to the battery being charged.

Does the above look like your charger? It's a higher powered model, so the details may be a little different.

[ Edit: the above may be all wrong; I'm just guessing that the red and black signals go to the enable and 12 V. But then these are labelled pins 1 and 2, with pins 3 and 4 elsewhere. So maybe the red and black are actually the CAN interface. If so, connecting 12 V to that may have blown up the CAN interface. You may well not be using that interface, so it may be OK for you. ]

[ Edit 2: Now I'm thinking that maybe there is a cable with 4 or more wires in it, and only the red and black come out the end. But you could if desired cut the cable near the end and gain access to the 4-pins of enable input (2), relay output (2), and CAN bus (2 or 3 if CAN GND is included). But again, just a guess. ]

[ Edit 3: So any pictures would be very helpful (as Crackerjackz suggested). ]


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## Angelito (Jul 5, 2013)

This is the picture of the wires sticking out of my charger. I was told that you just have to short the two wires to make the charger work. I accidentally applied 12 volts to it and now the charger will just keep blinking red-green-red continously and stop for several seconds and will blink red-green and red again. This happens even if I short the said two wires...This is despite the fact that the batteries are currently just at 3.28 volts. There seems to be no reaction from the charger even after i hooked it up to my battery pack of 48 volts, 16 calb cells of 180ah each. 

http://www.diyelectriccar.com/forums/picture.php?albumid=665&pictureid=4553
This is the picture of my charger 

http://www.diyelectriccar.com/forums/album.php?albumid=665&pictureid=4561


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## Angelito (Jul 5, 2013)

I think that you are correct that the wires are connected to enable. Based on other diagrams, you may connect the wires to a contacting relay so that it could be controlled by a bms. The bms will apply 12 volts to contacting relay to open it and cut off the power to shut down the charger if the desired voltage/state of charge is reached. 

If I have blown-up the 12 volts power source, is there any way to repair it or by-pass it so that i can use an external 12 volts power source instead? In doing so, will it still maintain its smart charger function: e.g. shutting off after the 100% state of charge is reached? 

Thank you for your help guys.


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## Coulomb (Apr 22, 2009)

Angelito said:


> This is the picture of the wires sticking out of my charger.


Well, it certainly looks like there are just those two wires.



> I was told that you just have to short the two wires to make the charger work.


That would be correct, if you had a non-CAN model. But you seem to have a CAN model (see attachment).

The CAN models ignore the enable signal all together. Or at least the older models did. If there are no other wires (other than mains in and battery out), then these two have to be CAN H and CAN L (CAN bus High and Low).

Did you want a CAN model? With a CAN model, you get a lot of flexibility, but you have to have some microcontroller that will send the appropriate CAN commands at least once every 5 seconds.



> I accidentally applied 12 volts to it and now the charger will just keep blinking red-green-red continously and stop for several seconds and will blink red-green and red again.


Huh. According to the old manual, that code means Overcharged. If that was true, it should change when you disconnect the battery. According to the old firmware, there is a flash code red-green-red, but I can't find anywhere that the appropriate error bit (ERR_CODE bit 3) is set. So the firmware in the new chargers must be different. I'd ask your supplier for a proper manual so you can figure out how to use it.

If the red and black wires are CAN high and low as I suspect, them shorting them together won't blow anything up (though it will cause some CAN bus errors). Applying 12 V to them... I don't know; it depends on the CAN drivers. My guess is that the CAN interface chips may have fried, and the red-green-red code (did I get that right?) means CAN comms error. But you would have had that from new, without anything sending CAN commands. Do you have something sending the appropriate CAN commands?


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## Angelito (Jul 5, 2013)

The charger that they sent me I think has no CAN capability..Even if there is, the other pins to connect the interface have not been installed..At least that is how it looks like in the outside, since there are no other pins or connectors other than those two thin wires.. I need to open the charger and take a picture of the inside just to be sure... At any rate, I will not be needing the CAN, except if the only way left for me to keep the charger is to have the CAN installed. 

[email protected] has the same experience as mine in this thread. However, his charger has an extra green wire and he used the green wire to apply negative and the red wire for possitive to make his charger run. Mine has no green wire.. only the black and red... 
http://www.diyelectriccar.com/forum...harger-battery-not-connectediiii-55452p5.html

If assuming the wires are for enable and +12 volts are running through them.. What could have possibly been blown when i applied 12 volts to them? Could it be just a resistor that can be changed? You may suggest for other ways to go about it.. thank you..

Yes. The red-green-red code is suppoed to mean overcharged in the manual. However, the blinking signal does not change even if i disconnect the battery pack.. It does not even change even if i short the red and black wires and even if I "un-short" them..


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## PStechPaul (May 1, 2012)

My WAG is that the green wire is actually chassis ground, which is likely connected directly or through a small resistor to the circuit ground. Your friend may be able to verify this with a DMM, or you might see if you get a reasonable reading from your red wire to chassis, and apply 12 VDC to see if that works. It is always good practice to use a current limited supply or a resistor to avoid releasing magic smoke.


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## Coulomb (Apr 22, 2009)

PStechPaul said:


> My WAG is that the green wire is actually chassis ground, which is likely connected directly or through a small resistor to the circuit ground.


I would not think so, based on the older chargers.



> Your friend may be able to verify this with a DMM, or you might see if you get a reasonable reading from your red wire to chassis


Sure. But I think you won't.



> and apply 12 VDC to see if that works. It is always good practice to use a current limited supply or a resistor to avoid releasing magic smoke.


I'd leave that as a last resort.

If you are opening up the charger, I'd sure be interested in any photos. Especially where the red and black wires connect to the control board (guessing that will be near the top right corner of the control board).


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## Coulomb (Apr 22, 2009)

Angelito said:


> At any rate, I will not be needing the CAN, except if the only way left for me to keep the charger is to have the CAN installed.


With the old models, if yours is a CAN model, it has completely different firmware flashed into it, and it can only be used in "CAN mode". If the clip of the charger label a few posts back is from your charger, then it sure seems like it's a CAN model. But it may be all different with the HQ (newer) models.



> If assuming the wires are for enable and +12 volts are running through them..


I've just realized that red and black are the colors that TCCH use for +12V and enable, respectively (and green for zero volts reference).



> What could have possibly been blown when i applied 12 volts to them?


It depends on whether it's really a CAN model or not, and whether even if it has CAN hardware, whether that's what's connected to red and black. Really, this is appalling help from the manufacturer.



> Could it be just a resistor that can be changed?


It might be that simple (though it will be a surface mount resistor or fuse, possibly buried under some black gunk), but it might be that there is nothing wrong with the charger, you just haven't been given enough information on how to connect it.


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## Coulomb (Apr 22, 2009)

I've changed my mind; I don't believe that this is a HQ model. HQ models, as far as I can tell, have only one color of error LED (red). So this must be (as the label states, duh) a standard TCCH model. (Though it also seems to say it's a CAN model).

So there are still the two possibilities: red and black are +12V and enable with respect to pack negative, and CANH and CANL.

One way to tell would be to see if there is about 12 V (11-13 V) from the red wire to pack negative. Be careful with this measurement. Actually, you don't need the battery connected, so that makes it safer (but it can still bite through a resistor across the output relay). If you see the 11-13V, that would indicate that the charger is non-CAN and is working OK.

If it's not a CAN model, then indeed there is a case where bit 3 of ERR_CODE can be set, and therefore you would get the red-green-red code. It's when the charger stays too long in one state (but I think this does not include state 0, where the battery is not even connected yet). Each stage (bulk, absorb, others) have a maximum time you can stay in that state. If the charger exceeds that time, it assumes that something is wrong and you get this error. It's called "overcharged" in the documentation, but it's not in the sense that most of us would think of overcharged (as in, too much electrical charge, usually therefore overvoltaged). So if the enable circuit is preventing the charger from charging with any actual current, then perhaps eventually you should get this error. But I can't see why you would get this error when just switching it on.

You're sure it's not red-green-red-green-red, right? That would be "communications interface fault", indicating that it's a CAN model and it's not getting valid CAN packets for the last 5 seconds.


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## Angelito (Jul 5, 2013)

I am certain that the signal is red-green-red and it will stop for 5 or more seconds then red-green-red again.. there is always a gap of 5 or more seconds between the red-green-red signals.. I was not able to open the charger as yet.. Been very busy with office works, i will post the pictures of the inside as soon as I opened it. 

The supplier in China does not answer my email anymore.. I thought all the while that the charger part is just as easy as hooking up the batteries and plugging to the socket.. 

Please bear with me if some questions are quite stupid, I have elementary electrical knowledge but i do understand your instructions.. Tnx


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## Angelito (Jul 5, 2013)

Coulomb you are correct, the red wire indeed goes to CAN+H and the Black goes to CAN-L. There are 6 pins and the others are nt connected to any wire.. Here is the picture of the connection. 

http://www.diyelectriccar.com/forums/picture.php?albumid=665&pictureid=4593

You are also correct that my charger has a CAN. Here is the picture of the board of the CAN-CON. 

http://www.diyelectriccar.com/forums/picture.php?albumid=665&pictureid=4585

Here is the picture where the thin wires came from, it is connected to that white plastic connector. 

http://www.diyelectriccar.com/forums/picture.php?albumid=665&pictureid=4577

I checked the diode that has a connection to the CAN+H, there seems to be no problem. None of the components that I have tested so far show any issue. There's nothing that appears busted or out f ordre. Could there be just an eror in the circuit somewhere? Can I utilize the other pins bunched with the CAN-L and CAN+H in rigging the charger to make it work? 

Thank you.. I am still working on uploading more pictures, the website requires me to join a group so that I can upload more pictures. I am still figuring out how to.


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## PStechPaul (May 1, 2012)

It looks like the 6 pin connector has only two installed pins, for CAN-L and CAN-H. There are also pads for 12V+ and 12V-. See if the proper voltage is on these points. If not, maybe you can apply +12V to see if things start working (but use a current-limited source).










BTW, you can see the images by clicking on the links. Then right-click on the image, select "Copy", and then in the post where you want it to appear, use Ctrl-V or right-click and "Paste".


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## Angelito (Jul 5, 2013)

AS you have noticed in the picture above, there is a resistor placed on series with -12V in the six pins, consistent with the diagram in the picture of Coulomb below. 

http://www.diyelectriccar.com/forums/attachment.php?attachmentid=68865&d=1479130695

I have tried shorting the two pins, the 12+ and the 12-, while the charger is unplugged. There is a clicking reaction in the relay on the DC output side. The blinking also changed from red-green-red to red-green flash. It seems that the charger keeps a lot of stored electricity even after it has been unplugged. The flashing appears to mean battery disconnect in the manual. 

Could this be the missing link? Should I try to short this while charger is plugged and hook it up with my battery pack? I am thinking of making further test, maybe attaching a resistor and monitor if it will get hot or be busted. Thanks for your help guys..


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## Coulomb (Apr 22, 2009)

Angelito said:


> AS you have noticed in the picture above, there is a resistor placed on series with -12V in the six pins, consistent with the diagram in the picture of Coulomb below.


Well, it seems to be a 3k resistor (marking 3001). according to my photos of a HQ model. (So now I'm flip flopping to stating that this is definitely a HQ model, although the red/green LED disagrees with what the scant documentation says).

[ Edit: it's also not obvious to me that this resistor is in series with DGND. It looks like it's across the 12V+ and 12V- pins, but it's hard to tell from the photos. ]

It could be as you say. I have no idea what "12V-" means; one presumes it would be different to the connection on J13 that is marked "GND".

I'd be tempted to try connecting 12V and TEMP on J13 (perhaps while the charger is turned off but has stored power, as you have been doing), so see if it does the same thing. That at least would be something we know a little about (guessing that it's the same as 12V and Enable on the older models).



> I have tried shorting the two pins, the 12+ and the 12-, while the charger is unplugged. There is a clicking reaction in the relay on the DC output side.


If that's with the battery connected, then this is great news. It means it's out of state zero, ready to charge.



> The blinking also changed from red-green-red to red-green flash. It seems that the charger keeps a lot of stored electricity even after it has been unplugged.


Yes. There are three 220 uF 400 V capacitors (four in 2 kW models) holding up the DC bus out of the PFC stage. As long as they have more than about 40 V (on old models at least), the DC/DC will power the electronics of the charger.



> The flashing appears to mean battery disconnect in the manual.


Well, that's strange. Was the battery disconnected? If so, why would the output relay come on? You could connect the battery backwards at that point, and I thought that was most of the point of the output relay (to protect the charger from a reverse polarity battery).



> Could this be the missing link?


As above, yes it could. Maybe they were supposed to provide a model with the 12V+ and 12V- signals instead of CANH and CANL. Maybe the new models will do CAN or non-CAN without a change of firmware.

It's extraordinary that we have to guess or reverse engineer this!



> Should I try to short this while charger is plugged and hook it up with my battery pack?


I take it from this that your shorting experiments were with the mains power and battery disconnected.

I'd say first try connecting 12V and TEMP on J13, preferably via a resistor of say 1k to 10k. If TEMP is the enable input, then you should end up with more than 2 V at the enable input, which should turn on the charger (possibly at reduced output, depending on the value of the resistor).

If that works, try connecting the battery but not the mains (not while enabled anyway). If the charger attempts to actually charge the battery, the DC bus should collapse suddenly, and the LEDs should go out.

You might also get information from the small red LED on the control board, marked D1 (about middle height, below J13). When it attempts to turn on or off the output relay, that LED should change from a slow flash (1 per second) to a fast flash (5 per second). Perhaps repeat your 12V+ to 12V- shorting to see if the fast flash precedes the click you hear.

One further data point: could you measure from 12V+ to 12V- when the charger is powered up, using a multimeter? I'm guessing it will be around 11V, but if it's more like 24 V, then 12V- may be a power supply that is 12V negative with respect to DGND (hence 24V negative with respect to 12V+). In that case, shorting the 12V+ to 12V- may be shorting part of the output control, and that's not what you'd want.

There must be data on this somewhere; if anyone knows of it, please holler. I can't find it.


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## kennybobby (Aug 10, 2012)

That's a totally new design and layout from the earlier boards so all bets are off.

Before connecting or shorting together any unknown pins i would want to trace out the circuits to try to determine the nature of the signals.

For example, trace the red and black wire pair back onto the control board.

i would guess that TEMP is a temperature measurement input, and the 12V+/- are positive and negative supplies, but it should be measured to verify before trying to jumper anything.

Maybe the CAN bus can be read with a sniffer to determine what is being sent to get some insight.


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## Weisheimer (May 11, 2009)

TC Charger moved to the new processor design at the end of 2013.
I have only seen CAN versions, but that doesn't mean that there aren't others.

They switched from using the 89LPC938 processor and moved to the NXP LPC11C14F/301 which is what they used in at least one of the CAN adapters for the ver 1.5/1.6/1.7 model versions.
They call the new control board version 3.5
It uses most of the same PFC/Power control chips, though surface mount now.

The CAN commands are still the same.


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## Coulomb (Apr 22, 2009)

Weisheimer said:


> TC Charger moved to the new processor design at the end of 2013.


Huh, interesting. I've heard bits and pieces for years. But the non-CAN models seem to have been supplied the same, still with the 7-pin round connector, or at least a 3-wire cable, until quite recently.

Ooh! I see that this is a high voltage version, and they have tidied up the 8 diodes for the secondary onto the main board now, with one long heatsink clip for the 8 diodes.

I also see that there is a 12V- test point over near the power supply end (moved from the main board to the left end of the control board). That suggests to me that 12V- is a power supply, not a control signal, and should not be shorted to 12V+, especially when the charger is running. So I'm in agreement with KennyBobby here; let's not short things together until this is sorted.

It looks to me that Angelito was supplied with a CAN model when he should have received a non-CAN model. The question is, can the CAN model be used in non-CAN mode by changing a few wires? It looks possible, but I think it's too early to tell.


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## Angelito (Jul 5, 2013)

> Well, that's strange. Was the battery disconnected? If so, why would the output relay come on? You could connect the battery backwards at that point, and I thought that was most of the point of the output relay (to protect the charger from a reverse polarity battery).


I tested the DC output, there is no power coming out even after the clicking sound. I think its another relay that opens to know whether or not the battery pack is connected or if there is no reversed polarity. After the clicking sound follows the red-green signal that means battery disconnect. 



> One further data point: could you measure from 12V+ to 12V- when the charger is powered up, using a multimeter? I'm guessing it will be around 11V, but if it's more like 24 V, then 12V- may be a power supply that is 12V negative with respect to DGND (hence 24V negative with respect to 12V+).


It shows 13 volts while the charger is plugged in.



> They switched from using the 89LPC938 processor and moved to the NXP LPC11C14F/301 which is what they used in at least one of the CAN adapters for the ver 1.5/1.6/1.7 model versions.


Weisheimer I think the layout in the charger in your pictures are the same as mine except for the missing pins in my charger. If that is your charger, my guess is that we can solve this riddle finally if you can test your charger if there is a continuity in the connection between 12V+ and 12V-. If there is, then all I have to do is to just connect them in my charger. 



> It looks to me that Angelito was supplied with a CAN model when he should have received a non-CAN model. The question is, can the CAN*model be used in non-CAN*mode by changing a few wires? It looks possible, but I think it's too early to tell.


I am thinking of the same thing too. I think they attached the wires on the wrong pins. My question now is, is there a need for CAN+H and CAN-L to be shorted for the charger to function? If there is no need for them to be shorted than what is the function of CAN+H and CAN-L? 

One final question is, will it produce some sort of spark if the 12V+ and 12V- are shorted if they are power sources in themselves and not just a continuity in the circuit. My charger does not produce any spark if they are shorted.


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## Coulomb (Apr 22, 2009)

Angelito said:


> I tested the DC output, there is no power coming out even after the clicking sound.


Ok, so the MOSFETs haven't started swtching; it's still in state zero. In the old models at least, there is a high value resistor that leaks a small amount of current past the output relay (I don't know why).



> I think its another relay that opens to know whether or not the battery pack is connected or if there is no reversed polarity.


I see no reason for a second output relay. However, there are 1 or 2 small relays on the control board now, that connect to J15, indicating the presence of mains and whether it's charging. Shorting 12V+ and 12V- may have taken away whatever power supplies those relays, but it seems unlikely.



> After the clicking sound follows the red-green signal that means battery disconnect.


If the red-green pattern is actually red-black-green-black... (black meaning neither the red or green LED is lit), then this indicates state zero: ready to charge, but no battery detected. Output relay is off.



> It shows 13 volts while the charger is plugged in.


Ok, another of my theories is shot down. It seems like 12V- may be the same as GND (our DGND), although wait... now I think I've figured it out (duh):*it's likely different because it's through the isolated DC/DC:










This is from the 2 kW HQ model user manual. It's obviously not totally accurate, since there are clearly now only 2 transistors driving the LED outputs (and a diode, not shown on this diagram). However, the labels 12V+ and 12V- (even though they're called 13V and 13V-GND on the connector) suggest strongly to me that the 12V+ and 12V- signals are in fact isolated power supply outputs. So shorting these will do nothing good; don't do it any more, even with the mains power disconnected!



> ... you can test your charger if there is a continuity in the connection between 12V+ and 12V-. If there is, then all I have to do is to just connect them in my charger.


? I don't follow that logic. As indicated above, I think that shorting these two is a bad idea. You still have some options, such as shorting 12V and TEMP on J13. Note: while 12V+ is likely isolated from the mains and the battery pack, 12V and GND are probably relative to battery pack negative, just like in the older models.



> My question now is, is there a need for CAN+H and CAN-L to be shorted for the charger to function?


Certainly not. Shorting these will do no hardware harm, but it will introduce CAN bus errors, and who knows what the reaction to that might be.



> If there is no need for them to be shorted than what is the function of CAN+H and CAN-L?


These are the two active signals in the CAN bus, used to communicate to the charger what voltage and current you want, and the charger also tells you what the present battery voltage and charge current is (these may not be what you asked for). See the Wikipedia page on the CAN bus.



> One final question is, will it produce some sort of spark if the 12V+ and 12V- are shorted if they are power sources in themselves and not just a continuity in the circuit.


It could well do that.



> My charger does not produce any spark if they are shorted.


Well, it seems to be a pretty small DC/DC converter, in fact if it looks like the one I think it is, it's much the same size as the opto-couplers (maybe a little taller, I can't see from the photos I have). So its output current would be small, hence you haven't noticed a great arc. However, it's likely not designed to have its output short circuited, so it could quickly overheat.


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## Angelito (Jul 5, 2013)

> If the red-green pattern is actually red-black-green-black... (black meaning neither the red or green LED is lit), then this indicates state zero: ready to charge, but no battery detected. Output relay is off.


Yes that is the blinking patern now, red-black-green-black, after a clicking sound.. Is this not a good sign which means that the charger is looking for the battery pack and once the battery pack is hooked up, it will start to charge?


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## Weisheimer (May 11, 2009)

I'm sorry to say that I do not have any of the new version chargers here.
I made those pictures in 2014 when I had one of the 4kw models apart.

It would seem to me that the non-CAN version utilizes a different connector on the control board, and the wired connector is simply moved to the control board connector appropriate to the version.

You certainly appear to have a CAN version of charger and will either need to get it replaced, or else implement a CAN controller.


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## Coulomb (Apr 22, 2009)

Angelito said:


> Yes that is the blinking patern now, red-black-green-black, after a clicking sound.. Is this not a good sign which means that the charger is looking for the battery pack and once the battery pack is hooked up, it will start to charge?


It could be good, but not if you have to short 12V+ to 12V- to make it happen. Does it do that if you connect 12V and TEMP on J13 (two connectors over from the CAN connector) ?


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## Coulomb (Apr 22, 2009)

I found this in the manual for the new 3.3 kW charger:










It seems reasonable that the new chargers would all have the same new firmware, so that confirms that the red-gree-red pattern that you were seeing Angelito was a communications failure (no CAN messages).

Unfortunately, it looks like the 3.3 kW model is CAN only (though with 3 selectable bit rates; I can't see how the bit rate is selected/changed). There is also a 2016 manual (on the Chinese site only) for a 1.8 kW model, which seems to be available in lead acid, lithium, and CAN models. Again, it's unclear whether the CAN model is able to charge without using the CAN bus.


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## Coulomb (Apr 22, 2009)

I'm repairing a charger that has a direct short at the output of the bridge rectifier. It looks like it has to be one or both of Q7 and Q8, the PFC MOSFETs. I've never had these fail yet, and have never seen a part number for them, so I pulled one of them from a dead charger:










It's an IXYS 600 V, 24 A (@ 25°C) 165 mΩ max device, datasheet here:

http://ixapps.ixys.com/Datasheet/IXKH24N60C5_IXKP24N60C5.pdf

Edit: I expect a wide variety of parts could be found in these positions; this is just one of them.
Another had a marking code of 6R165P, which is an Infineon IPW60R165CP, 650 V, 21 A (@ 25°C), 165 mΩ max device, datasheet here:

http://www.infineon.com/dgdl/Infine...n.pdf?fileId=db3a304412b407950112b42d915e489f

On the charger with the short after the bridge, the 150Ω resistors had crumbled.


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## pdove (Jan 9, 2012)

I am pretty sure I replaced this on Steves charger back in 2015, It may be in one of these threads. I know I emailed him a bit so not sure what was recorded here. It also, blew the fuse and I may have replaced the relay and resistors (150ohm) on the input. I'll look tonight and see if I made any notes.


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## Coulomb (Apr 22, 2009)

I have two chargers for repair at the moment. Both have these blade fuses instead of the usual ceramic(?) fuse at the output:

















The second photo is below the board, showing that there must be plated slots in the PCB. In other words, this appears to be a deliberate part of the design, not some hack someone thought was a good idea. There even seems to be room for a second fuse in parallel with the first (groan).

My understanding is that these blade fuses usually have a 32 V DC rating, though I found that Littelfuse make some that go to 80 VDC (but don't look exactly like these). I sure hope that they have better DC ratings than that. One charger with these in it is a 60 V nominal, 90 V max, the other is 84 V nominal, 102 V max.

Perhaps these blade fuses are only supplied in the lower voltage models?

Has anyone else seen these?

Anyone have an opinion on their suitability? Personally, I think it's a bad idea, and I'm tempted to replace them with HRC fuses. But leaded fuses don't seem to be available over 15 A, and a 25 A HRC fuse seems to be 10 x 38 or 10 x 31.5 mm, a little awkward to solder in.

[ Edit:*These are marked Littelfuse 257 32V. See also the closeup photo, attached.]


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## piotrsko (Dec 9, 2007)

you are correct about the 32 vdc rating. However I have been using them for years with no apologies up to 10 amp @ 220vac, have a couple 1 amp in 200 V DC meter circuits for wiring protection. the voltage rating is for breaking the arc that may or may not form when the over current event occurs. I have also used the rated 32 volts and had an event where the element added to the arc and the fuse became an arc lamp for a moment. the equipment it was protecting was destroyed however.

is this use incorrect? probably. will it mostly work for common failures? perhaps. The exceptions are the bugger, however, and are very exciting. wire lead fuses might have to be installed like U bend resistors on a PC board.

Oh: the current rating goes unreliable at higher voltages. might be higher, probably lower. I Never tested for that


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## kennybobby (Aug 10, 2012)

Mount the fuse vertically and cover it with heat shrink tubing--then it will look like what they used on all the other chargers... It's silly to use the blade type fuse without putting in a socket to change it out, defeats the purpose it seems.


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## pdove (Jan 9, 2012)

> I'm repairing a charger that has a direct short at the output of the bridge rectifier. It looks like it has to be one or both of Q7 and Q8, the PFC MOSFETs. I've never had these fail yet, and have never seen a part number for them, so I pulled one of them from a dead charger:


I remember now. It was one of the first chargers I looked at. The Mosfet drivers on the control board were also fried. I never did get that one working again.


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## Coulomb (Apr 22, 2009)

pdove said:


> I never did get that one working again.


Only one of the PFC MOSFETs was fried on this one. While waiting for the replacement parts (bad time of year for deliveries), I left one of the originals in and powered it up on the bench from a 50 V 3 A power supply. It was able to charge my 24 V test battery at up to 2 A. (It was a CAN bus version; much easier to test.) The lone PFC MOSFET with no heatsink got a bit warm, a little over 50°C. So I'm confident that this was just a single PFC MOSFET failure, which also took out the pre-charge resistors.


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## Coulomb (Apr 22, 2009)

I'm finding that when the MOSFETs are blown, there is a good chance that the drivers (U15 and U16, IR2110L6) also go, and often also take out one or more of the gate resistors (R57/R66/R65/R74) and their paralleled diodes (Q12/Q16/Q17/Q21). When the driver chips go, they can often present a low impedance to the 15 V power supply. The latter is current limited (I think by Q9 and R11 on the Comp pin of the VIPer power supply chip), so it can collapse the 15 V and also 12 V power supplies to a few volts. [ Edit: as KennyBobby reported in post one for his charger. ] This can cause a wild goose chase attempting to fix the power supply when it is the load that is at fault. 

The boost diodes (D4/D7, BR6) and the boost capacitors (C38/C46, 100 nF) can be tested in circuit. I found that one of the diodes was reading bad reverse leakage due to the driver chip being blown up. I'm starting to think it's worth replacing the drivers in pairs, regardless of whether they appear to be blown or not. (In other words, the likelihood of one driver being blown if the other is blown is so high that it's quicker and cheaper to replace both than to try and figure out if one is still working.)

The gate resistors can easily be measured in circuit as well. However, their paralleled diodes are not so easy to test. I finally decided on using my current limited power supply set to 2.0 V and 0.1 A, applied directly across the gate resistors. Mine has a handy digital display showing the present voltage and current. In one direction, I measure about 1.03 V (1.0 V theoretical), and 0.75 to 0.76 V in the other (with the diode conducting about 25 mA). I was surprised to find quite a few gate diodes not working. One gate resistor was high resistance (325Ω); this reads as 2.00 V and 0.0 A from the power supply. It's like a multimeter resistance measurement, except with a 100 mA current instead of 1-2 mA, and the units are tens of ohms (resistance) or volts (diode). So this power supply test can test a gate resistor and its paralleled diode in one operation (two readings).

Edit: Note that Q12 and R57, the second of the four sets of date diodes and resistors when reading left to right, are *upside down* compared to the others. You may find it easier to work with the pins on the diodes; when the positive lead from the current limited power supply is on the anode (middle pin all on its own), the diode should conduct, so you should see around 0.75 V rather than 2.0 V.


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## kennybobby (Aug 10, 2012)

That's a good troubleshooting tip. We spent a lot of time using a multimeter trying to measure and determine if the resistors and diodes were okay--kept getting inconsistent readings that were confusing...

Plus good catch on the viper voltage--our supply may have been pulled down by the shorted drivers and we measured lower voltage.


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## Coulomb (Apr 22, 2009)

I've updated my most recent post before this one to note that one pair of the four gate diodes and resistors is upside down, making it hard to remember whether to expect the diode to conduct or not. As i mention in the edit, it becomes easier if you probe the gate diodes rather than the gate resistors. I find that multimeter leads on the power supply clip leads make for more accurate positioning, and poking through the soft black gunk without having to remove it.

My score with the present charger was three gate diodes and one gate resistor open circuit or high resistance. When the gate resistor is high resistance, you can bet that the diode is gone, and the driver as well. In fact, it might be worth starting with the gate resistors and diodes, instead of with the driver chips, since the former are fairly easy to measure, and act a bit like fuses to indicate that there has been high current here. In my case, the carnage appears (so far) to have stopped with the chip before the drivers, a CD4001B quad NOR gate.

Edit: Note also that if the 10R gate resistors on the control board have blown, there is a good chance that the 1R0 gate resistors on the main board (right near the MOSFET gates) are also toast. Three out of four of these turned out to be open circuit.


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## Coulomb (Apr 22, 2009)

My latest thoughts are that when replacing MOSFETs, it could be a good idea to do some tests while the old MOSFETs are out, before the replacements are in.

Firstly, after checking that there are no solder dags reducing the gap between bus+ and bus- (between the big red jumpers), you could insert only J7 and with a power supply set to 50 V and 2.5 A, check that the PFC stage inverts the bus up to ~ 390 VDC.

Now with all jumpers in, you can test the MOSFET drivers and the desaturation protection circuit. You should see a 500 ns pulse on pin 1 (LO, Low side Output) of both drivers. With no MOSFETs in place, the high side outputs will be at +15 V (through the boost diodes D4/D7 and the conducting output transistors in the MOSFET drivers). To check these as well, connect a clip lead and a 150Ω resistor between GND (which you have access to for your DSO ground) and one of the primary wires of the transformer. That brings the midpoints of the MOSFET bridge down near ground, so that there is 15 V to power up the high side drivers. With this clip lead in place, you should see a just under 50% duty cycle output, nearly 15 V p-p, on pin 8 (HO, High side Output) of both MOSFET drivers. The 50% duty cycle comes from the RS latch formed by two of the gates of U12 (CD4001, quad NOR gate).

This test caught a problem with the present charger; the printed circuit pad to one of the driver chips had lifted, leaving LIN (Low side INput) floating. There was no output from that driver's pin 1 output, but tracing back, I found nearly 50% duty cycle on PWM chip (U14, UC3846) pin 14 (B OUT, second output). From previous experience, I know there should be a narrow pulse, around 2 μs wide, on that output (with MOSFETs present). The lack of gate output disabled that half of the desaturation protection circuit, which is what narrows the PWM chip's output pulses.

Not having MOSFETs in place (or not working or not driven correctly) will look like a massive desaturation error, since there is nothing pulling the midpoint of the MOSFET bridge (either side of the transformer primary winding) towards ground when the low side gates are driven high. This is the reason for the 150Ω resistor above; this with the 1kΩ resistors R59/R58 form a voltage divider that puts some 2 V at the midpoint, just like a badly desaturated MOSFET. (Ok, I guess MOSFETs don't strictly desaturate, but the principle is the same; there should not be 2 V drop across the conducting MOSFET, or certainly not for long). In the attached DSO screen photo, you can see the normal ramp (thin black line) has a large spike added to it, with peak amplitude some 1.9 V. Some of that may be due to the inductance of the wirewound 150Ω resistors I used. These spikes at pin 4 of the PWM chip (Current Sense +) is what causes the PWM chip to shorten the output pulses. When you see the 500 ns pulses instead of the near 50% square waves at the PWM chip output (and hence at the driver chips' LO outputs), you know that the desaturation protection is working. Without this check, it would be difficult to know that the desat protection is working, and a repaired charger could go into the field without a major protection circuit in place.

Desaturation protection only applies to the two low side MOSFETs. If something goes wrong with the high side MOSFETs, like a dead short, this will not cause an immediate problem, and won't be detected, until the low side MOSFETs conduct. As far as I can see, if one or both of the low side MOSFETs short first, the desaturation protection will not prevent shoot through, and consequent catastrophic failure of at least two MOSFETs, and likely their driver(s) and the CD4001 latch.


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## Coulomb (Apr 22, 2009)

I finally got to work on a HQ (2014ish) model today. I thought I'd share with you some grizzles about the repairability or lack thereof, of these chargers.

In the attached images, you can see U11 (a voltage reference, I think) on a tab off the daughter board that protrudes into the mother board. I can't think of a reason for that, other than sheer bloody mindedness!

There are parts on both sides of the daughter board now, making access to the parts on the side facing the charger internals quite challenging.

For example Q1, which seems to drive the power supply's transformer (no longer a Viper chip with a heatsink soldered to it) is so far under the power supply transformer (or more likely the multi-turn inductor) that it's difficult to even see the part, let alone probe it or replace it. The attached photo is the best that I could do with a mirror, to show you a third of it. The green outline is my guess as to where the rest of it is.

Models between this one and the ultra compact ones (1.8 / 3.3 / 6.6 kW models) are even more different from the original models, e.g. using surface mount resistors for the battery and charger-output voltage dividers. They may no longer use low tolerance parts that are calibrated out with EEPROM contents.


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## Coulomb (Apr 22, 2009)

It occurred to me that it might be worthwhile replacing C38, the 220μF 400 V capacitor near the MOSFETs, with something a little higher voltage, higher ripple current rated, and/or longer life, since this capacitor is the main thing that saves the MOSFETs from overvoltage spikes. I would have liked to have found a 10,000 hour model, but they don't seem to exist at 400 V+.

I asked my friend Weber to use his capacitor selecting expertise on the problem, and he came up with these three suggestions, in order of decreasing quality (best one first):

1) Rubycon 420VXH270MEFCSN25X40, 270μF 420 V, 5000 hr, 105°C, 2.17 A @ 10 kHz ripple current.

2) United Chemicon ELXS451VSN221MQ40S, 200μF 450 V, 5000 hr, 105°C, 1.72 A @ 50 kHz ripple current.

3) Nichicon LGX2G221MELA35, 220μF 400 V, 5000 hr, 105°C, 1.6 A @ 50 kHz ripple current.

All these are available from Digi-key (see above links). Unfortunately, the best one is only available from there, considering the other 3 suppliers that I regularly use. They're not cheap either, but I think in this application they would be a wise investment. The other 2 or three capacitors away from the MOSFETs are only there for 100/120 Hz duty, so they could be nearly any 105°C model.


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## Cinquecento (Aug 23, 2017)

Thanks for sharing all the info in this thread! It really helped me to sort out the problem with my 2kW charger - it had exactly the same problem as the one described in post #165.
The 220uF 400V caps were popped (black lids had come off on two of them) and there was a bad soldering on one of the relay pins.
Symptom was that it failed to charge the battery pack, and the LED flashed red-green with 1s intervals (code for "Battery disconnected").
I replaced the caps (with EPCOS 220uF, 400V - DigiKey part no 495-6285-ND) and re-soldered the relay pin, and now it seems to work again!


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## dimitri (May 16, 2008)

Guys, since I no longer have one of these chargers I can't verify myself, but wanted to know. I'd appreciate if one of you can confirm.
There is an internal 12V supply which is exposed on pins 2 and 3 of the 7 pin DIN connector, which is used to enable/disable the charger by a BMS system.

I'd like to confirm if this 12V supply is or isn't isolated from the DC output of the charger? Can someone do a continuity test between pin 2 of the DIN and negative DC output?


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## pdove (Jan 9, 2012)

dimitri said:


> Guys, since I no longer have one of these chargers I can't verify myself, but wanted to know. I'd appreciate if one of you can confirm.
> There is an internal 12V supply which is exposed on pins 2 and 3 of the 7 pin DIN connector, which is used to enable/disable the charger by a BMS system.
> 
> I'd like to confirm if this 12V supply is or isn't isolated from the DC output of the charger? Can someone do a continuity test between pin 2 of the DIN and negative DC output?


Well, I can make measurements when I get home but the 12 volt is isolated with a transformer but the negative is the same as the DC bus,


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## dimitri (May 16, 2008)

pdove said:


> Well, I can make measurements when I get home but the 12 volt is isolated with a transformer but the negative is the same as the DC bus,


Thanks Paul, that's what I suspected. Appreciate your help.


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## Coulomb (Apr 22, 2009)

The 2014 models have a 12 V output that is isolated from everything, certainly including the battery being charged. But they don't have the 7-pin round connector. They have an array of sockets near the output cable, so presumably different models could have the 12 V brought out. Or any such model could be modified by taking off the lid and replacing the cable with a different one(s), plugging into the input and outputs required.

There is also a "TEMP" input, which I suspect is much the same as the ENABLE input on the 7-pin round connector. But I can't find details. On the one 2014 model I have here at present, only the CAN+ and CAN- signals are brought out. It's an isolated CAN output.


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## kennybobby (Aug 10, 2012)

*TCCH Elcon microcontroller replacement*

Here's some pictures of what's involved to replace the processor chip. Over time i've found it easier to remove the 5-pin programming header than melt it trying to get a soldering iron into a cramped place. Also beware of melting the plastic plunger of the button switch.

Here's the before, blown processor and 10 Ohm R7 resistor (in the 12V line to 3.3V regulator)









The black coating gets under the chip making it nearly impossible to remove without damage.









Cleaned up:









Soldered on a new processor chip:









Program it and good as new...


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## Coulomb (Apr 22, 2009)

*Re: TCCH Elcon microcontroller replacement*



kennybobby said:


> ... Program it and good as new...


Wow, you make it sound so easy. And probably it is, after the first one or two.

Any idea why there was the yellow gunk over one end of the processor? Surely not to discourage you from replacing it should it ever blow up? Surely they don't think they can keep the processor part number a secret?



KennyBobby said:


> ... nearly impossible to remove without damage


Is that damage to the old chip, or to the PCB? I assume the latter; do you find you can usually repair the PCB to a "good enough" state? I think I've had similar problems with some of the other surface mount chips, like the MOSFET drivers, and so far have been able to repair the board well enough.


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## kennybobby (Aug 10, 2012)

Yeah the programming is easy for me--Paul does it!

The yellow gunk was holding a resistor that was added from ground to pins 15 and 16 of the processor--guess that was to pull down the unused pins.











The yellow gunk makes a good tell-tale indicator--it turns brown or black if exposed to a thermal source (and heat makes it easy to crumble off). So if a chip or capacitor has gotten hot it shows up.











As far as removing the processor chip it usually breaks off some of the tiny leads. i have had traces and pads lift off the board (e.g. on Dimitri's charger) but used tiny wires to make repairs.


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## Tomppa (Jun 30, 2012)

Hi!

This thread is very interesting. I read the whole thread.

Quick question:

I have a 1,5 kw TcCharger and Soliton Jr in my conversion. I was going to use external relay to disconnect charger's output and battery during driving conditions. Why the relay? I was thinking of protecting the charger from AC ripple, but I found out, from this thread, that there is internal relay on the output too? So, is it ok to just leave the charger's output connected all the times?

P.s Ot. I have a DC-DC also from TcCharger. I'm using 100uH inductor in series with positive wire to protect it.


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## Coulomb (Apr 22, 2009)

Tomppa said:


> I was going to use external relay to disconnect charger's output and battery during driving conditions. Why the relay? I was thinking of protecting the charger from AC ripple, but I found out, from this thread, that there is internal relay on the output too? So, is it ok to just leave the charger's output connected all the times?


Yes, the relays will be off when there is no mains input. Presumably, your motor controller will be off while charging. There are only small capacitors (1 nF or less) to chassis from positive and negative output. So no need for an external relay.


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## pdove (Jan 9, 2012)

Tomppa said:


> Hi!
> 
> I was thinking of protecting the charger from AC ripple, but I found out, from this thread, that there is internal relay on the output too? So, is it ok to just leave the charger's output connected all the times?
> 
> P.s Ot. I have a DC-DC also from TcCharger. I'm using 100uH inductor in series with positive wire to protect it.


There are already two filters on the input of the charger. I don't believe AC ripple is a problem there is also a Transorb.


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## Tomppa (Jun 30, 2012)

Thank you for your helpful replies. You have saved me some time and a relay.

I admire the time and dedication you have put into reverse engineering these devices and writing this thread. Good work!


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## Coulomb (Apr 22, 2009)

pdove said:


> There are already two filters on the input of the charger. I don't believe AC ripple is a problem...


I believe that @Tomppa was talking about AC ripple on the pack, caused by the motor controller and/or sudden traction loads or regen, causing currents in the wires from the charger to the pack. There have even been fuse blows from this current, e.g. after sudden acceleration. It would also stress the capacitors in the output section of the charger.


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## Tomppa (Jun 30, 2012)

Sorry, I should have been more explicit.



> ..Tomppa was talking about AC ripple on the pack, caused by the motor controller


Correct.



> There have even been fuse blows from this current... It would also stress the capacitors in the output section of the charger.


I have read this too. People are having issues especially with DC-DC. It's running hot (input caps), making strange hissing noises, blowing the fuse etc.
I don't know if TcCharger's DC-DC has been designed with proper filtering, hence the 100uH inductor.

Maybe some charger designs don't have an internal relay on the output side and ripple is an issue. Or you are charging when driving via range extender


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## drdonh (Aug 8, 2008)

Hi,

I am reporting here a problem with my Elcon 1500 charger, that doesn't seem to fit with others reported here. I've been using my charger for about 8 years now, and recently it has intermittently stopped providing a charging current. The LED functions as normal, flashing during startup and then going to full red, but with no current to batteries. Sometimes, a small current might start up (0.1 amps), and sometimes (but not often) this will eventually creep up to the full 11 amps that it normally charges with. I have a 105V system, charging lithiums.

I took the cover off, and occasionally I can hear crackling noise from the 2.2uf capacitor indicated in the photo. Taping on the capacitor, and the line-in terminal from the mains (the black wire) as well as the inductor coil that's next to it, with a stick seems to get the crackling going. Might this just be poor solder connection, or would a failed capacitor or other part cause these problems. It looks like a lot of work to lift the board out to see underneath, so I was hoping for some advice here before looking further.

Cheers, Don


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## weber (Apr 22, 2009)

Almost certainly a bad solder joint.


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## pdove (Jan 9, 2012)

drdonh said:


> Hi,
> 
> I am reporting here a problem with my Elcon 1500 charger, that doesn't seem to fit with others reported here. I've been using my charger for about 8 years now, and recently it has intermittently stopped providing a charging current. The LED functions as normal, flashing during startup and then going to full red, but with no current to batteries. Sometimes, a small current might start up (0.1 amps), and sometimes (but not often) this will eventually creep up to the full 11 amps that it normally charges with. I have a 105V system, charging lithiums.
> 
> ...



Coulomb had this issue and its documented here: post#145
http://www.diyelectriccar.com/forums/showthread.php?p=754002#post754002


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## drdonh (Aug 8, 2008)

I just read the post. The conclusion is the crackling noise is normal, that the capacitors are naturally accoustically active. Perhaps tapping them just helps make them active, and doesn't mean anything in terms of my issue. In any case, the charger was now able to just complete a charge cycle after going out for a brief drive. 

I am starting to wonder if the problem is software related. In my battery management strategy, to try and stay in mid SOC, at the start of the driving season ( I do not drive the car in the canadian prairie winter), I start by charging the batteries to 90% (105V), zero my amp counter, and then typically only charge to 80% after each use using the 90% charge reference point as defined earlier. As it turns out, I think this is first time I ever tried charging starting at nearly 90% to just top up the charge to 90%. Yet, the full red LED lit up indicating it was wanting to charge at full rate. Is the charger correctly limiting the amps, but not indicating correctly with the LED status light that it is in the final charge mode (i.e. blinking red)? I will need to experiment with this some more.


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## Coulomb (Apr 22, 2009)

drdonh said:


> I took the cover off, and occasionally I can hear crackling noise from the 2.2uf capacitor indicated in the photo.


That one is directly across the mains, after the input fuse. So all it does is correct the power factor slightly, and absorb a few mains transients. So the charger doesn't need that one to be perfect to operate. Something else must be limiting your chargin.



> Taping on the capacitor, and the line-in terminal from the mains (the black wire) as well as the inductor coil that's next to it, with a stick seems to get the crackling going. Might this just be poor solder connection, or would a failed capacitor or other part cause these problems.


It seems that the capacitor has an intermittent connection inside it. It's an "X" type safety capacitor, meaning it has fuses built in, and these are notorious for blowing. It's the price of safety. So if you remove the main PCB for other reasons, definitely check its soldering and replace if the soldering seems OK.



> It looks like a lot of work to lift the board out to see underneath,


Yes, it is quite the hassle; I wish they were designed more for repairability.

It could be working as intended, but perhaps your sense resistors are getting old and have drifted off value. These are half watt metal film resistors that are actually accessible from the top of the board. Give it at least ten minutes after charging before fiddling with this part of the circuit. Study where the diodes are, and use plenty of light and magnification as needed to read the nominal value of those resistors (R10 and R20; they won't be 600 kΩ for your model, more like 100 kΩ or 120 kΩ. The problem could be the two pairs of resistors at the bottom of the chain (R8/R9/R34/R35 on the control board); these are also accessible without taking out the main PCB. For your model, they should likely be 2.0 kΩ (R9 and R35) and 3.6 kΩ (R8 and R34). You'll need to use the control board photo to find them, and scrape off some black gunk with a wooden tool to be able to access the ends. [ Edit: the control board resistors are 0805 surface mount parts). ]

If all these check out OK, then it's a fair bit more work to fix it.


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## Coulomb (Apr 22, 2009)

I can confirm that the PFC MOSFET gate driver transistors (Q6, Q7 on the control board) are indeed SMD versions of the S8050 and S8550. I read SMD codes 1HC and 1HD respectively. They're not trivial to find; RS-Online and element14 (Newark) don't seem to carry them. I found Mouser's SS8050/SS8550 parts to be a near match, though I haven't put them into service as yet. The Link is to the Australian Mouser site, but others should be able to find it from there.


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## drdonh (Aug 8, 2008)

After some on and off again erratic behaviour reported in earlier posts, my charger finally quit completely, sometime in the middle of a charging cycle. Opening the unit, obvious was the burnt precharge resistors (in the picture), which also melted some of the relay case. The resistors now measure essentially an open circuit. 

Measuring resistances (while in the circuit board) across the bridge rectifier terminals, all resistances are high. Similarly, the Mosfets (i.e. Q7 and Q8) do not measure any obvious shorts. No blown fuses. Could the problem be the Viper chip or whatever else powers the relay, as its de-energizing is what might have caused the resistors to burn up? Although wouldn't everything shut down if the aux power when down?

Would the next step in troubleshooting be replacing the resistors and powering up again to see what happens, for example seeing, if there is aux voltage power? With no batteries connected, the current in the resistors should fall quickly after starting up assuming the transistors are not shorted, so this should be safe enough I imagine.


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## Coulomb (Apr 22, 2009)

drdonh said:


> Opening the unit, obvious was the burnt precharge resistors (in the picture), which also melted some of the relay case. The resistors now measure essentially an open circuit.


If you didn't power up the charger after the failed charge, that means that the relay opened (the input relay is across the pre-charge resistors, and normally shorts them out except for the first half second or so). It seems likely that the 15 V power supply collapsed (it drives the relay, as well as the power section electronics). My guess is that something shorted the 15 V power supply.



> Could the problem be the Viper chip or whatever else powers the relay, as its de-energizing is what might have caused the resistors to burn up? Although wouldn't everything shut down if the aux power when down?


If the red/green LED was still working (for more than 10 seconds or so), then no, the Viper powers the 12 V power supply that runs the processor and LEDs.



> Would the next step in troubleshooting be replacing the resistors and powering up again to see what happens, for example seeing, if there is aux voltage power?


I'd first check for a short on the 15 V power rail; see earlier posts for details. Replacing the 150 Ω resistors isn't easy without taking out the main board, which takes some time, patience, and some tools that you might not have handy. If the 15 V power supply doesn't seem shorted (some 325 Ω is normal, from memory), I'd consider applying a current limited power supply set to about 52 V and 0.5 A to the input of the bridge rectifier, bypassing the failed pre-charge diodes for now. You won't need pre-charge as the power supply is current limited. Then check for 15 V and 12 V power, and see if anything gets hot.



> With no batteries connected, the current in the resistors should fall quickly after starting up assuming the transistors are not shorted, so this should be safe enough I imagine.


If you don't have a suitable power supply handy, that's probably worth doing. I'd attempt to do a temporary repair of the pre-charge resistors without taking out the main board, to save time and effort. Be ready to disconnect quickly, in case the MOSFETs are shorted and the relay doesn't come on. I'd check for a short on the DC bus first, to save smoking the new resistors.

If the DC bus is shorted, it's a long repair: remove main PCB, remove dead MOSFETs, check for dead driver chips (I find one of U15 or U16 always blows if the MOSFETs blow), and check for blown gate resistors and diodes. I've just done one like this, and it had a fairly high carnage:
* Bridge rectifier
* PFC MOSFETs (at least you don't have this)
* U16
* Several gate diodes and resistors
* U12 (commonly fails when the MOSFETs and one of U15/U16 blow)
* Input relay contacts welded
* I replaced two of the 220 μF capacitors; I suspect that C38 drying out and/or going high internal resistance is the cause of most charger failures that take out the MOSFETs
* R28 (68 Ω in series with the input relay coil) was high resistance

Thankfully, the 12 V power supply, processor, etc were all fine.

My guess for your case, if you find a short on the DC bus, is 4 MOSFETs, U15 or U16, two 10R resistors and two BAW56 diodes, and possibly the 4001 (U12). That may give you an idea how much work is ahead of you, and whether you want to take it on or not.


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## Coulomb (Apr 22, 2009)

The database errors are preventing me from maintaining the original version of this post, which is one of the ones I refer to myself most often. My apologies to readers who may be sick of seeing it.

*Warning: if the mains input is connected to actual mains, the "GND" mentioned here is at lethal potential to the ground pin of the mains, and your body. In other words:
GND is HOT!
I believe that these jumpers are only intended for use with a current limited power supply of about 52 V.*

I've finally sussed out the use of the three main jumpers on the Elcon/TC charger daughter board (the one with most of the chips on it, including the processor and small red LED).

J8: short to disable the PFC stage. This is a good thing when debugging with a 52 V current limited power supply, because the MOSFETs will switch at 50 V (~2 V drop across the diodes) rather than 385 V.

J7: Short to force 240 V mains detection. Without this jumper, the mains sensing circuitry will decide that your 52 V power supply is too low, and will disable both the PFC stage, and the PWM stage. So the MOSFETs won't switch at all without this jumper in place if you are using a bench power supply.

J3: Without a battery detected, the microcontroller won't enable any switching. By inserting a jumper with a 1.8 kΩ resistor (see below), you will get a moderate duty cycle. This is ideal for testing. [ Edit: I used to recommend a 3.3 kΩ resistor for a very low duty cycle, but on some chargers, there isn't enough voltage to get the UC3846 to start generating pulses. ]

So the sensible combination of jumpers is as follows, in order:

1) *All jumpers out*. 50 V across the main MOSFETs, but they are not switching. Good for finding shorted MOSFETs. Leave the power supply current limit at 0.5 A or less. You may need 52 V or more at the AC input to get the Viper chip to start so you can verify that power is reaching the control board. That verifies the 12 V power supply. Hearing the pre-charge relay pull in verifies the 15 V output.
2a) Optional. *Only J3 in*. For the truly cautious, this will give the MOSFETs a short burst of switching, then immediately stop switching them (as it realizes that the mains is not present). You should be able to measure part of the voltage from the next step at the output, slowly decaying. It might be only a half or even a quarter, so a peak of 4-12% of maximum voltage, or 5-16% of nominal voltage.
2b) *All jumpers in*. 50 V across the MOSFETs, which are now switching. You should see some 15% of maximum rated voltage (about 20% of nominal voltage) at the charger output (negative output terminal and PCB pad, see below). Power supply limit can stay at 0.5 A or less.

At this point, you should be confident that the MOSFETs are switching properly, because the energy in the bus capacitors is about to increase about 8² = 64 times. Use a DSO if there is any doubt. One thing to check is that there is some dead time for both half cycles; test point T34 is for this. Dead time is when this point is low. T34 is awkward to get to under U12, so just use pin 11 of U12 (middle pin). There should always be some time during each half cycles when this test point is low. [ Edit: Actually, T34 is just the logical OR of the A and B outputs. To know that there is dead time, I like to see a sloping rising edge, yet fast falling edge, at the LIN low-side inputs. ] I like to use both my J3 jumpers (1.8 kΩ and 3.3 kΩ), as well as no J3 jumper at all.

3) J7 in, *J8 out, J3 out*. Now there should be ~ 385 V on the DC bus (the MOSFET power supply), but the MOSFETs are not switching yet. The power supply current limit needs to be at least 2 A, preferably 2.5 A, to get started. It may take ~10 seconds to get close to maximum bus voltage, at which point the current should fall to around half an amp (it jumps around a lot on my power supply, which is two 26 V supplies in series).
4) J7 in, J8 out, *J3 in*. Now there should be ~385 V on the DC bus, and the MOSFETs should be switching. The power supply limit needs to be at least 2 A, possibly 3 A. Now you should read about 110% of the maximum rated voltage (about 150% of nominal voltage) at the charger output. This could exceed the voltage rating of the output capacitors; if so, don't leave it running like this for very long. I prefer to start with a 2 A current limit, even though it takes over 10 seconds to reach maximum bus voltage. That gives me a chance to switch off if things don't seem right, and there is a slightly better chance I won't damage too much.

If it passes all this, it's time to reassemble the charger and test with a real battery and mains power.

Here is my collection of jumpers:










The jumpers appear to be 2.5 mm spacing, but I used the more commonly available 0.1" header pins (2.54 mm spacing). The slight mismatch makes them stay put without falling out. Note: there is black junk over all of the jumpers, in fact over 95% of the PCB, so you need to clean the area around the jumpers. Also, the holes fill up, which is a royal pain. I use a paper clip to push through the holes. You may need to clean the back of the board where the jumpers come through as well. A wooden chopstick, flat at one end and sharpened at the other, is useful for this. I sharpen the pointy end with a pencil sharpener, and the flat end with a small file. (Thanks for the idea, KennyBobby.)

The two jumpers at the left are shorted; the heatshrink is to keep them together and to make them easier and safer to handle. These are for J7 and/or J8. The jumper with the 1k8 resistor is for J3 only.

Here are the locations of the jumpers, and some close-ups:










































The power connector on the left of the control board is useful for connecting to ground with a multimeter negative lead or DSO ground lead (though you get tons of glitches when the MOSFETs are firing). I had a plug already made up, but only plugged it into the top pin, so there was no danger of shorting the 15 V power supply. For temporary multimeter negative leads I often use the ground via circled in orange. For +15 V, the top of L1 (in the top left hand corner of the PCB) is handy.

At the output of the driver chips (U15 and U16), you should see ~ 12 V p-p on the low outputs (pin 1), and around 60 V p-p on the high outputs (pin 8). The latter is because you are adding the ~ 48 V from the MOSFETs switching (50 V from the power supply less some diode drops), plus the ~ 12 V from the boost power supply (pin 7, this should be a square wave with the low end around 12 V to around 60 V at the top end, about 12 V higher than the MOSFET outputs).

When all is fixed, you should see some DC output, but not necessarily at the actual positive output terminal. This is because the micro doesn't see a battery, and so won't connect the output relay. There is a resistor across the relay, so you should see something at the positive output terminal. But there is a spare relay position (only populated for very low voltage chargers whose output exceeds 20 A), where a multimeter positive lead can be conveniently placed:










The negative lead can be placed on the negative output terminal (not interrupted by the relay being open), or the negative output lead if it's still connected.

In my case, I was working on a 288 V nominal unit with a 13:7:8 transformer ratio (many of the transformers seem to have their ratios written on them, particularly the 2 kW units). The :7 and :8 parts add; only the higher two voltage units have this arrangement. Treat it as a 13:15 ratio transformer. Lower voltage chargers will have rations like 13:9 or 25:8. In my case, I expect roughly 15/13 x 50 V = 58 V; I was seeing a little over 60 V.

[ Edit: added sentences re test point T34 and dead time. ]
[ Edit: 2 A is a good value for the final jumper test. ]


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## pdove (Jan 9, 2012)

drdonh said:


> Would the next step in troubleshooting be replacing the resistors and powering up again to see what happens, for example seeing, if there is aux voltage power? With no batteries connected, the current in the resistors should fall quickly after starting up assuming the transistors are not shorted, so this should be safe enough I imagine.


I would check L10 on the main board over by the viper. this has opened on several chargers I worked on.


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## drdonh (Aug 8, 2008)

Further to my troubleshooting attempts after discovering the pre-charge resistors had burnt out on my charger .....

I temporarily replaced these resistors (soldered overtop actually) with 100 ohm resistors, as these were the closest I had to 150. Plugged the unit in to main power, but with no battery pack load connected, and observed that the relay energizes fairly quickly, there is a brief rise of smoke from the resistors, and the LED status lights start blinking as would be expected. Even after 10 minutes plugged in, everthing seems ok, the resistors are not smoking any more. I measure a small AC voltage across the resistors (~2 volts), but I suppose this should be zero, and is perhaps not normal.

I then try the charger connected to the battery pack and plug in the unit. Again, a small puff of smoke from the resistors, and then, when the other relay that connects the batteries kicks in, and the charging current rises, the resistors start smoking again, and I quickly unplug the unit. The precharge relay is energized during the whole time, as I hear it turn off a few seconds after the main line is disconnected.

I suppose this has to be the relay that is at fault. Yet, the contacts do not look arced out, as in a picture I saw earlier in this thread. I suppose this could even be poor solder contacts for the relay. I only have spare time now and again to work on this, so it will take a few days to investigate this further, especially if I have to lift the board. Thanks to all those who contribute to this thread, as it is very helpful.


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## Coulomb (Apr 22, 2009)

drdonh said:


> I temporarily replaced these resistors (soldered overtop actually) with 100 ohm resistors, as these were the closest I had to 150. Plugged the unit in to main power, but with no battery pack load connected, and observed that the relay energizes fairly quickly, there is a brief rise of smoke from the resistors


Yes, I've also seen the puff of smoke from the wrong type of resistor. See this post (and especially one few posts after that one) where I show what type they are from the factory, and what I recommend that they be replaced with. The occasional puff of smoke is OK for a few times while testing.



> I measure a small AC voltage across the resistors (~2 volts), but I suppose this should be zero, and is perhaps not normal.


It's definitely not normal. The charger is only drawing about 2.5 watts at this point, so that's about 1.6 Ω of contact resistance. So that's about R₁R₂/(R₁×R₂) = 1.55 Ω with the 50 Ω across it. At full power, that's approaching 10 A across this 1.55 Ω resistance, or nearing 15 V across those 100 Ω resistors, or over 2 W each. They certainly can't take that for long. But the relay contacts would be dissipating up to 15 V × 1.6 Ω = 24 W. So that would be cooking the contacts, or the solder joints, even if the contacts don't appear to be pocked or flashed from arcing.

So it's either really bad soldering under the relay contacts, or more likely the relay needs replacing. This is where I get them from in Australia. Translate that to whereever you get your parts.



> Thanks to all those who contribute to this thread, as it is very helpful.


Yes, a special shout out to Kenny and Paul who got the ball rolling, and did the heroic schematic trace.


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## Coulomb (Apr 22, 2009)

Back in September,



kennybobby said:


> The yellow gunk makes a good tell-tale indicator--it turns brown or black if exposed to a thermal source (and heat makes it easy to crumble off). So if a chip or capacitor has gotten hot it shows up.


Amen to that, brother! I've noticed that a lot of the yellow gunk goes brown, and dismissed it as an aging effect. But now that I've had two chargers go bang when I applied mains power (which is usually after the 2-hour re-assembly job), and it was R3 or C11 both times, I'm starting to respect this browning. What a wonderful repair aid! Now, if only they were easier to get the main board in and out of, they'd be a good repair job. [ Edit: See this post for where R3 and C11 appear under the PCB. ]

Now I'm thinking "if it's gone brown, replace the part!".

I've never seen the yellow gunk go black. Do you sometimes get carried away with the heat gun, perhaps?


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## Coulomb (Apr 22, 2009)

I finally figured out how to secure the L15 heatsink firmly, when the bolt and/or slot become worn and the bolt turns instead of being prevented by turning by the slot. L15 is the smaller of the two rectangular inductors on the battery side of the charger, and its heatsink is held between the PCB and the chassis/heatsink with a single M3 bolt, with a hex head, and the chassis/heatsink. The aluminum of the slot wears easily, so this happens a fair bit. I find it hard to source these small hex-head (not hex socket) bolts. With this technique, it's possible to use ordinary countersunk or cheese head bolts. (An alternative might be pan heads that are filed to about 5.3 mm wide on two sides, but I did not have any of suitable length to hand.)

I found that I could jam a large jeweler's flat blade screw driver under the bolt, from the side of the chassis, to jam it into place. Then the usual long-nosed 5.5 mm socket tightens the heatsink with the usual nylock nut. I was previously trying to jam a smaller flat blade above the PCB, just under the nylock nut. But fortunately the bolt for this heatsink is near the edge of the chassis, so it's possible (with this one at least) to access it from the side of the charger. The end of the screwdriver is seen edge-on in the upper part of the diagram.

I hope that readers can figure out what I'm trying to say from the attached diagram. The upper part of the diagram is viewed from the side of the charger, while the lower part is viewed from above.


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## drdonh (Aug 8, 2008)

I believe I have fully fixed my charger now. 

The contacts on the start relay did in fact have a bit of arcing, as seen on the photo. That was enough to fully shut the unit down, eventually. I cleaned up the contacts with a bit of emery paper, and the charger is back to normal. As a recap, the symptom leading up to the final total failure where the unit went totally dead due to burnt pre-charge resistors, was that at random startups, the unit would never reach full charging current, or the current rise was much slower than normal. Perhaps this will be helpful to others in their troubleshooting.

P.S. My electrical repair experience is more with home appliances like toasters and microwaves. Based on the components I see used in those applications, I would never have guessed this start relay is rated at 16A. It did last 9 years, but it still seems kind of small considering all the power for the charger goes through it. 

Thanks for everyone's help, as I did go through the whole thread in this venture.


----------



## Coulomb (Apr 22, 2009)

I find this image of the cleaned-up control board very useful. I thought one of us had posted it ages ago, but I can't find it.

2.17 MB Jpeg; 3264 x 2448 pixels.


----------



## Coulomb (Apr 22, 2009)

Another day, another TC charger repair.

This one has a few unusual features. First, the power supply has changed, and it no longer runs from 52 VDC at the mains input. I'll have to pump in 15 V and 12 V separately; this will be a nuisance. It seems that this model is from very late 2013, just before they changed to a new processor. So I don't think that there are many of this model out there with the non-Viper power supply on the main board. However, later models with the non-8-bit processor seem to have a very similar power supply located at the mains end of the daughter / control board.


















There is no Viper chip; it's replaced by an 8-pin SMD power supply chip and an 800 V (!) MOSFET, part number 2N80 (pdf). This awesome MOSFET has a maximum RDSₒₙ of 6.3 Ω. I don't think that's a typo, it's not meant to be milli-ohms. That's the compromise with a high voltage MOSFET.

There are some new connectors, perhaps some are for testing. From the silk screen labels, one is designed for a fan. R29 (the resistor in series with the input relay) is now R62, a pair of SMD resistors.

The power for the power supply chip seems to come at least initially from 5 (!) 1 MΩ (!) resistors in series; R6-R14 along the edge of the PCB. I suspect that once the power supply starts, it can "power itself" from a lower voltage. I'll find out soon enough.

The 150 Ω pre-charge resistors had burned up; nothing startling there. However, they lay flat on the PCB now. The main problem seems to be bad soldering on the two 2.2 μF capacitors. This seems to have generated heat, which caused some gunk to ooze from the capacitors. They both measure quite low capacitance, and one lead is basically corroded to nothing.



















[ Edit: Added a sentence about the 5 1 MΩ resistors. ]
[ Edit: Added "pre-charge" between "150 Ω" and "resistors". ]


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## Coulomb (Apr 22, 2009)

This model is also the first one where I've found the use of copper banding for reinforcing heavy current tracks. There is also the usual thick tinned copper wire (top left of the attached photo).


----------



## Coulomb (Apr 22, 2009)

Initial rough schematic of the non-Viper power supply. [ Edit: now not so rough; nearly complete. ]

The Dialog Semiconductor iW1691-08 chip (formerly iWatt) is supposed to be able to bootstrap with a maximum of 15 μA (10 μA typical) into Vin.

I've had no luck starting up this (partially) repaired charger so far; shorting three of the five 1 MΩ resistors allows a hiccup start from 52 VDC, with the input relay pulling in for a tenth of a second, then ~3 seconds of wait and repeat.

Edit: I ended up "bootstrapping" the power supply with 26 VDC at the mains input, 2.5 A current limited, and using J8 to force the PFC stage to come on. The other half of the power supply provided 15 V via the connector at the left end of the control board. It used just over 100 mA. It took 10-20 seconds to charge the bus capacitors to just under 400 V. Part way up, the LEDs at the right hand end started flashing, indicating that the power supply was now providing "isolated" 12 V. When I took away the 15 V power, the LEDs continued to flash. When I took away the 26 VDC, the bus voltage slowly fell. When it got to about 140 V, the relay dropped out and the LEDs stopped flashing. So the power supply, at least without any modifications, requires some 140 VDC to keep itself alive. It's different, but it can be worked with.

Edit: 2018/Sep/10: C15, R59
Edit: 2018/Sep/13: More detail, e.g. earths, D18-D20, 12V supplies, etc.


----------



## Coulomb (Apr 22, 2009)

As I'm putting this charger back together, testing some usual suspects for bad resistance values, I notice that the brown gunk over several parts is actually _conductive_. Not massively, only a meg-ohm over a few millimetres, but that's not what I'd prefer to have between the legs of thousand volt rated capacitors.

I cleaned it up as best I could (not very), and replaced it with neutral cure silicone.

Initially I had mistaken it for the familiar yellow gunk that had gone brown with heat. So my early thought was wow, this charger has really gotten hot. But there were a few pieces of the yellow gunk elsewhere, and it had browned only very slightly. I think they ran out of yellow gunk and grabbed something off the shelf that wasn't suitable.

I wonder how many more there are out there like that, and whether it causes problems.

Edit: on final mains test, I find that the stuff that's left _sparkles_. So I'll have to figure out a better way of getting rid of all of it. Sigh.


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## drdonh (Aug 8, 2008)

Hi I'm back,

Same problems as my earlier posts, where the precharge resistors burnt up again. I went through one iteration of replacing them, and it worked for several months. This time time, replacing them it can be seen they stay hot and smoke (observing before putting the cover on), so I unplug the unit. The solenoid contactor operates, so I suspect the problem is beneath the board, where there is poor connection. I really don't want to lift the board. 

My question is: Can the precharge circuit be replaced with a Thermistor type circuit to limit the inrush? It would be so easy to just to replace the precharge resistors with these, as this can be done without lifting the boards, at least in my case. 

Don


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## Coulomb (Apr 22, 2009)

drdonh said:


> ... replacing them it can be seen they stay hot and smoke (observing before putting the cover on)


When the start relay comes on, the pre-charge resistors should be shorted. So apart from a short puff of smoke at first start-up (and then only if you have the wrong type of pre-charge resistor that can't handle the pulse of power), they should not stay hot and certainly not be smoking. So it seems that although the relay is pulling in, it's not shorting the resistors properly. So the proper solution is to use the correct resistor types, and replace the relay. [ Edit: it's possible that the relay pins only need re-soldering. ] Having the relay contacts fail is a fault that has been seen before.

But as you say, that does require removing the main PCB, and that's a hassle for someone who has not done it many times before (like myself, Paul, and a few others). You might be able to replace the resistors with some sort of thermistor, I'm not familiar enough with them to know. But the full charge power will be going through that part, so it had better look pretty close to a short circuit [ edit: after pre-charge is over ] or it will dissipate a lot of power and fail itself in short order.

Another possible short cut: the coil leads for the relay are probably easy to get to from the top of the board; the 68Ω resistor is through-hole, so one end could be lifted. So you could possibly glue a new relay upside down to the PCB somewhere, and have the new relay short the pre-charge resistors properly. Use lots of silicone to make it all safe and vibration tolerant.


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## drdonh (Aug 8, 2008)

Resolved (probably): Problem of precharge resistors randomly burning out:

My earlier posts over the past year described the odd behavior of my charger, with interrupted charging and unknown blinking led error codes, but mostly related to burning out precharge resistors. I finally decided to remove the board and look underneath. A true test of patience. Consistent with Coulomb's advice, ALL the relay solder contacts seemed to have opened up, or nearly so. A picture is attached. I've been using this charger seasonally for 10 years, but this seems a weak point of the design. Not sure yet if I will just fix this up to original, or work out a new configuration that might last longer or be more serviceable. In any event, I thought I would post this information as it may be helpful to others.

Also, in doing this, it looks like R26 burnt out. Another hard-to-get-to part. Not sure how critical it is, looks like something related to noise suppression. Not sure what the ohm value was either.


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## Coulomb (Apr 22, 2009)

drdonh said:


> it looks like R26 burnt out. Another hard-to-get-to part. Not sure how critical it is, looks like something related to noise suppression. Not sure what the ohm value was either.


It's 10 Ω, per this schematic.

I'm thinking that these RC snubbers are vital for absorbing inductor energy when the power is interrupted, preventing other components from more catastrophic failure. They do seem to cop a beating, so give it a stout replacement.


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## drdonh (Aug 8, 2008)

Update: I reassemble my charger with a new relay and precharge resistor. Everything worked fine for about 4 charges, then it stopped again. The main LED indicator shows solid red, as is normal for charging condition, but there is no current. The circuit board LED blinks slowly, which I think is normal too.

I opened up the unit again, took some voltage measurements. There is approx. 280V across the red jumpers going to the HV DC output section, so I think the DC boost supply is working. The best anomaly I can see so far is there is no voltage (ac or dc) across the Points A and B (the step up transformer?) as in the circuit diagram posted in this thread. Is the problem in Q1-4? Could it be I mess something up, or precipitated a failure, when removing and replacing the board? Is there other voltage measurements I can do to get a better idea of the problem?

Thanks,


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## Coulomb (Apr 22, 2009)

drdonh said:


> Update: I reassemble my charger with a new relay and precharge resistor. Everything worked fine for about 4 charges,


Congratulations, so far...



> then it stopped again... The best anomaly I can see so far is there is no voltage (ac or dc) across the Points A and B (the step up transformer?) as in the circuit diagram posted in this thread. Is the problem in Q1-4? Could it be I mess something up, or precipitated a failure, when removing and replacing the board?


It seems that Q1-Q4 are not switching, or (unusually) they are open circuit. They usually fail short circuit, in fairly spectacular fashion. I don't think you've precipitated a failure; just really unlucky.



> Is there other voltage measurements I can do to get a better idea of the problem?


You'll just have to trace back from the gates to the drivers to the PWM chip and so on.

One gotcha is often the lack of enable signal, but then you'd be stuck in state zero, with the red-black-green-black cycle.

If possible, use a current limited power supply to power the AC input, and use the jumpers to prevent hazardous voltages as you probe. The troubleshooting topic has all the details.


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## Cinquecento (Aug 23, 2017)

I'm trying to fix my charger that died, the Viper chip is definitely dead so I will replace it. Also the D11 is broken - in the 'low_voltage.jpg' schematics it is specified as 'BR6' - I 'm trying to find somewhere to buy this component, does anyone have some hints what type of diode this is (suitable replacement part number)?


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## kennybobby (Aug 10, 2012)

The "BR6" diode was found on an older unit, but i found D11 marked as "U1J." on a newer chargger unit.

Look up MURS160 diode datasheet from ON semiconductor or Diodes Incorporated, a 1A fast diode with high voltage rating. i can post the datasheet if you can't find it with a quick web search.


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## Cinquecento (Aug 23, 2017)

Thank you very much for the information! I have ordered some Vishay MURS160-E3/52T parts, and some Viper 20A chips (from China). It will be interesting to see if it will work when I receive the parts and can re-assemble the unit. I have read your precautions and will use current-limited DC bench power supply when testing.


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## halestorm (Apr 28, 2009)

I have one of these chargers (PFC2500) that failed in this similar fashion, where the two pre-charge resistors near the relay have overheated. I started taking it apart with the aspirations of repairing it, but I'm never going to get to it.

Does someone want it?

You'll need to cover shipping, which won't be cheap. If you think there's any value in it for you then add a little extra, if you're so inclined. Mostly I want it out of my garage and into someone's hands that might be able to use it, if even for parts. If so, drop me a line and I'll figure out what it might cost to ship.


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## dtbaker (Jan 5, 2008)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*

I've been running a 1500w Elcon in my Miata for 6 years/20k+ miles.... just got the car back from the transmission shop (stripped all the teeth off 3rd gear), plugged in the car, and....

a popping sound under the hood, and no current to batteries.

I peeled back the little sticker where you can change the end-of-charge voltage, and note that instead of the usual blinking green LED, there is a rapid-blinking red LED.

Q: are there any diagnosis/reset steps I can take with the charger IN the car?

Q: is it likely dead, or likely to be repairable for something less than $300 ? If repairable, is anyone watching this thread interested in attempting repair?

Q: any ideas on how the transmission shop might have killed the charger, or is this just bad timing? It was working fine when I brought it in. Neither the input AC nor the output DC are particularly close to the transmission... I am planning to put the car up, pull the bellypan, and look for any wires that might have been nipped or shorted when the tranny was removed/replaced.


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## Coulomb (Apr 22, 2009)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



dtbaker said:


> a popping sound under the hood, and no current to batteries.


A popping sound is never good.



> instead of the usual blinking green LED, there is a rapid-blinking red LED.


That's a red LED. But it usually blinks slowly (once per second). The rapid-blinking means it's trying to close the output (DC) relay. Usually this only lasts a second or less.



> Q: are there any diagnosis/reset steps I can take with the charger IN the car?


You've pretty much just done it.



> Q: is it likely dead, or likely to be repairable for something less than $300 ? If repairable, is anyone watching this thread interested in attempting repair?


It certainly needs repair. Perhaps contact user PDove on this forum by private message; he's quite experienced and has repaired many of these.



> Q: any ideas on how the transmission shop might have killed the charger, or is this just bad timing?


I think it's just lack of regular use. The capacitors that the manufacturer uses aren't particularly long life types, and they tend to dry out in the heat that they are regularly subjected to. After so many years, they just can't suppress the voltage spikes any more, and take out the MOSFETs.


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## dtbaker (Jan 5, 2008)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



Coulomb said:


> A popping sound is never good.... Perhaps contact user PDove on this forum by private message; he's quite experienced and has repaired many of these.


mmmmm, thanks for the referral. sounds like my next step is to pull the charger regardless.

BTW I got a reply from Elcon, and their guess is that there is a short on the DC side, perhaps introduced by the transmission remove/replace or a dropped wrench or something while they had plugged in that popped the transistors.

Either way, a repair inside the box is beyond what I want to tackle, so my next step is remove and send it out for repair and/or replace.


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## pdove (Jan 9, 2012)

You can send it to me. I have repaired some with the FETs blown. I don't think Elcon will fix them at least I have heard from others that they just want to sell new ones.


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## dtbaker (Jan 5, 2008)

pdove said:


> You can send it to me. I have repaired some with the FETs blown. I don't think Elcon will fix them at least I have heard from others that they just want to sell new ones.


totally great news. I will send asap.... gotta pull it out which is a bit of a chore the way I have it mounting on my front battery tray. PLEASE diret email me shipping address etc so we can work out details.
- [email protected]


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## Cinquecento (Aug 23, 2017)

kennybobby said:


> The "BR6" diode was found on an older unit, but i found D11 marked as "U1J." on a newer chargger unit.
> 
> Look up MURS160 diode datasheet from ON semiconductor or Diodes Incorporated, a 1A fast diode with high voltage rating. i can post the datasheet if you can't find it with a quick web search.


Thanks! I have now replaced the Viper and diode D11, trying to trace the fault why there's no 12V. Now I think it's the windings on the transformer L1 that's broken. I think resistance between pins 1-3 and 4-5 should be closer to 0 than megaohms...
I will look at it some more to see if there is a part number or any type of identification on the transformer.

My guess is that for some reason high current was drawn from 160V bus through Viper FET which killed both the Viper and the transformer.


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## Coulomb (Apr 22, 2009)

Cinquecento said:


> Now I think it's the windings on the transformer L1 that's broken. I think resistance between pins 1-3 and 4-5 should be closer to 0 than megaohms...


Could be...  [ Edit: However, it's strange that 4-5 is also near open circuit. Are you sure you're penetrating the coating? ]



> I will look at it some more to see if there is a part number or any type of identification on the transformer.


I don't think you'll be able to find a new transformer (or multi-turn inductor) off the shelf. So it will have to come from a dead charger. PDove might be able to help, or even myself if you happen to be located closer to Australia than the USA.


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## pdove (Jan 9, 2012)

halestorm said:


> I have one of these chargers (PFC2500) that failed in this similar fashion, where the two pre-charge resistors near the relay have overheated. I started taking it apart with the aspirations of repairing it, but I'm never going to get to it.
> 
> Does someone want it?
> 
> You'll need to cover shipping, which won't be cheap. If you think there's any value in it for you then add a little extra, if you're so inclined. Mostly I want it out of my garage and into someone's hands that might be able to use it, if even for parts. If so, drop me a line and I'll figure out what it might cost to ship.


. 

You can send it to me


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## kennybobby (Aug 10, 2012)

*Re: Lack of Viper voltage*



Cinquecento said:


> Thanks! I have now replaced the Viper and diode D11, trying to trace the fault why there's no 12V.


i would recommend to use your DMM to check across all the components you can reach to verify they are good. Sometimes L11 gets blown.

It does seem odd that the winding from 4-5 on the P side of the xformer is open--maybe it is how you are counting the pins, try a reverse pin ordering to see if any continuity shows.


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## pdove (Jan 9, 2012)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



dtbaker said:


> I've been running a 1500w Elcon in my Miata for 6 years/20k+ miles.... just got the car back from the transmission shop (stripped all the teeth off 3rd gear), plugged in the car, and....
> 
> a popping sound under the hood, and no current to batteries.
> 
> ...


Ok, I have Dans charger. I am going to upload some photos for documentation purposes. As you can see it got real hot. All the staking has turned brown. There is a hole in one of the big caps on the input side of the charger close to the heat sink in the middle. Charger powers up with no faults but I could see little sparks coming out of that cap.


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## pdove (Jan 9, 2012)

Here are the photos


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## Coulomb (Apr 22, 2009)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



pdove said:


> I could see little sparks coming out of that cap.


I think I've seen little sparks from the large capacitor near the MOSFETs to one of the small capacitors nearby.


I've seen little sparks near the RC snubbers, like R3/C11, or R5/C37.


But never coming out of a capacitor 


I really wonder if this one can be repaired. It's unclear to me whether the yellow gunk going brown just indicates age, or indicates extreme heat, or just an accumulation of heat over time. Perhaps when the yellow gunk goes brown, the capacitors are near the end of their life.


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## Dan Muugi (Nov 6, 2019)

Hi guys
Im new to this forum, ive been working on electric motorcycle conversions in Africa, Kenya. Ive done one prototype with 72v 55Ah LiFe pack. i have been using an elcon TCCH1K5W charger. the 7 pin com connector was loose and some cables snapped. i attempted to resolder but obviously got the pins wrong since im still getting no communication from the charger.
does anyone have the pin layout for this?


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## pdove (Jan 9, 2012)

Dan Muugi said:


> Hi guys
> Im new to this forum, ive been working on electric motorcycle conversions in Africa, Kenya. Ive done one prototype with 72v 55Ah LiFe pack. i have been using an elcon TCCH1K5W charger. the 7 pin com connector was loose and some cables snapped. i attempted to resolder but obviously got the pins wrong since im still getting no communication from the charger.
> does anyone have the pin layout for this?


Schematic here: https://www.diyelectriccar.com/forums/showthread.php/tcch-elcon-1-5kw-charger-schematics-89470.html

Connector pinout in lower right corner of schematic


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## Dan Muugi (Nov 6, 2019)

pdove said:


> Schematic here: https://www.diyelectriccar.com/forums/showthread.php/tcch-elcon-1-5kw-charger-schematics-89470.html
> 
> Connector pinout in lower right corner of schematic


 so i was able to locate the 12v and gnd wires and re soldered them to pin 3 and 2 respectively but im having a hard time getting the rxd and txd wires. all wires have different markings, by any chance do you know the markings that are on the txd and rxd wires?


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## kennybobby (Aug 10, 2012)

Do you have it open, with the cover off? The round 7-pin connector routes to a 7-pin header on the control board. It is a nasty soldering job and heat shrink tubing should have been used to prevent shorting at the solder joints. Here is a picture showing the header and wiring.


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## Dan Muugi (Nov 6, 2019)

kennybobby said:


> Do you have it open, with the cover off? The round 7-pin connector routes to a 7-pin header on the control board. It is a nasty soldering job and heat shrink tubing should have been used to prevent shorting at the solder joints. Here is a picture showing the header and wiring.


thanks this is exatly what i needed


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## Dan Muugi (Nov 6, 2019)

so ive done the soldering but i still get the waiting for communication signal (green ledflashing)


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## Dan Muugi (Nov 6, 2019)

could the problem be something else other than comunication, the charger was operational, i can't see anything that's blown in the boards the led on the com board blinks red,while on the other side, bottom blinks green.


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## Coulomb (Apr 22, 2009)

Dan Muugi said:


> the led on the com board blinks red,while on the other side, bottom blinks green.


 The small red LED on the control (daughter) board near the 7-pin connector blinks red slowly (once per second or so) in normal operation. It should flash faster (about two to three times per second) when the relay is connecting; that should last only about 5 seconds max, and you should hear the relay click at the end of it.

The main LED (red/yellow/green and visible outside the case in normal operation with the lid on) flashes green when charging. [ Edit: when the battery is nearly full. ] So from your description of the LEDs, the charger is working.

What am I missing?


The usual problem getting these chargers started (assuming a non-CAN model) is that the enable signal isn't connected to +12V. Then you get stuck in state zero, with the main LED flashing R - G - R - G... (from memory).


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## Dan Muugi (Nov 6, 2019)

i should get green-red blinking while charging, also the values of actual voltage and current are at zero on my p.c


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## Dan Muugi (Nov 6, 2019)

Coulomb said:


> The small red LED on the control (daughter) board near the 7-pin connector blinks red slowly (once per second or so) in normal operation. It should flash faster (about two to three times per second) when the relay is connecting; that should last only about 5 seconds max, and you should hear the relay click at the end of it.
> 
> The main LED (red/yellow/green and visible outside the case in normal operation with the lid on) flashes green when charging. So from your description of the LEDs, the charger is working.
> 
> ...


i should get R - R blinking while charging, also the values of actual voltage and current are at zero on my p.c


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## Coulomb (Apr 22, 2009)

Dan Muugi said:


> the values of actual voltage and current are at zero on my p.c


Personal computer? That sounds like you are using the serial port via a suitable circuit (it's NOT RS-232), or are using a CAN bus adapter.

Is it possible to see the actual serial data or raw CAN bus packets? Just to indicate that the serial lines are working after the cable repair.

Or just more carefully check pins 6 and 7; these are the serial data lines, used for either serial interface or after the CAN "box". Perhaps just buzz them through with a multimeter and something small to poke into the 7-pin round socket pins. The serial data will also need "ground" (low impedance connection to battery negative), so that's pin 2.


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## pdove (Jan 9, 2012)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



pdove said:


> Ok, I have Dans charger. I am going to upload some photos for documentation purposes. As you can see it got real hot. All the staking has turned brown. There is a hole in one of the big caps on the input side of the charger close to the heat sink in the middle. Charger powers up with no faults but I could see little sparks coming out of that cap.


Need some help here: 

This charger says it is trying to set the voltage to 511 volts. What do you think is broke to get this wrong? Also, All the status bits are zero at the end of the message.

FFFEF04A020D141400000141DE530841DE5308C20327E042D73A49BCCD03700000000042D779380100C1EE4FC000000000438D0000432FFFFE00000000000000000000000000000000000000000000 
Internal Temperature is: 27.7905
fINTEMP_MIN is: 27.7905
fEXT_TEMP is: -32.7889
f_DC_VOL is: 107.6138
f_DC_CUR is: -0.0250
f_BATTER_VOL is: 107.7368
f_BATTER_TEMP is: -29.7889
f_VOL_TEMP_compensate is: 0.0000
f_PVC_Vout is: 282.0000
f_DC_vol_SET is: 432FFFFE176.0000
f_DC_cur_SET is: 0.0000
f_BATTER_CUR_SET is: 0.0000
f_DVDT_15M is: 0.0000
f_Ah is: 0.0000
FFFEF04A020D141400000141DE530841DE5308C20327E042D7A6E4BCD9D3B00000000042D779380100C1EE4FC000000000438D000043FFFEFE00000000000000000000000000000000000000000000 
Internal Temperature is: 27.7905
fINTEMP_MIN is: 27.7905
fEXT_TEMP is: -32.7889
f_DC_VOL is: 107.8260
f_DC_CUR is: -0.0266
f_BATTER_VOL is: 107.7368
f_BATTER_TEMP is: -29.7889
f_VOL_TEMP_compensate is: 0.0000
f_PVC_Vout is: 282.0000
f_DC_vol_SET is: 43FFFEFE511.9921
f_DC_cur_SET is: 0.0000
f_BATTER_CUR_SET is: 0.0000
f_DVDT_15M is: 0.0000
f_Ah is: 0.0000


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## kennybobby (Aug 10, 2012)

What's in the eeprom--does it look like it has normal data there?

Check the resistors of the voltage dividers that read pack and DC buss voltage.


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## pdove (Jan 9, 2012)

kennybobby said:


> What's in the eeprom--does it look like it has normal data there?
> 
> Check the resistors of the voltage dividers that read pack and DC buss voltage.


I didn’t read the eeprom but I don’t see how that could have changed.

I would suspect the resistors but it’s the target set voltage that is wrong the battery and dc output are spot on.


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## Coulomb (Apr 22, 2009)

*Re: TCCH Elcon charger troubleshooting - 9/25/19 failure*



pdove said:


> This charger says it is trying to set the voltage to 511 volts. What do you think is broke to get this wrong?


I'm really rusty on this stuff now. I vaguely recall that setting the voltage to something ridiculously high is normal under certain circumstances. It basically means "charge away - no restrictions". Remember that the charger is essentially current driven; the voltage check may or may not result in needing to reduce the charge current.

My vague memory tells me it might be to do with getting the relay on. Before connecting the output relay, you want the voltages to be much the same (charger output and battery voltage). To do that, I think they "puff" some charge into the output capacitors, then let it bleed back to about the battery voltage, then close the output relay so there is little surge current into the output capacitors. During this "puff" stage, it may be setting the output voltage set-point to a large value.

Is the output relay on?

Is the small red LED on the control board blinking rapidly? It does that when attempting to turn the relay on or off, mainly turning it on.

Not having the output relay on may result in zero status, I don't recall.

However, the DC volts seem to be very close to the battery volts, so that seems to shoot down that idea.

I'll be busy tomorrow, but I may be able to look in more detail after that.


----------



## pdove (Jan 9, 2012)

I should have added more detail. I wasn’t sure it was fixed so I only ran it for a minute or two. The red led goes into rapid flash the. The relay closed. Then it ramped up the voltage but I never saw any current so I shut it down. It definitely reached state 0 because the external led was flashing red. Maybe it is ok. I will try again and run longer to see what happens. In addition I had it out of the case sitting on the bench so I thought I’d better assemble it first. I only found two issues. The AC wires were brittle and the insulation was cracked. The 270uf cap had torn insulation and was arching. I taped it with Mylar. Will update after I fix the wires and reassemble.


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## pdove (Jan 9, 2012)

The charger was exhibiting weird behavior. The output relay would close weather the charger was enabled or not and even if there was no battery. I could make it open or close by connecting a meter to R20 so.....

I decided to check some parts on the control board. D9 is reading 0.15 volts with the probes in either polarity. This is on the pull up to 12 volts of the transistor that controls the output relay. I guess it was affecting the turn on threshold. There may be other thing wrong there but I did check the battery sense circuit and it seems intact but that makes sense taking into consideration the charger was reading the battery correctly. 

If I can find a diode I'll replace and try again.


----------



## Coulomb (Apr 22, 2009)

pdove said:


> The output relay would close weather the charger was enabled or not and even if there was no battery. I could make it open or close by connecting a meter to R20 so.....


That sounds like there is a bad solder joint somewhere, or the resistor is cracked internally. However, that's contradicted by the fact that the data reads good values. Oh wait; D12 and R2 are across the relay contacts. D12 should be reverse biased for this, so perhaps D12 is leaky or shorted? That would explain those symptoms, I think. It would see battery voltage at the output of the charger. Maybe the charger is also not generating power at all.




> D9 is reading 0.15 volts with the probes in either polarity. This is on the pull up to 12 volts of the transistor that controls the output relay.


That might be because the relay coil is across that diode. Did you remove it from the circuit to test it?


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## pdove (Jan 9, 2012)

Coulomb said:


> That might be because the relay coil is across that diode. Did you remove it from the circuit to test it?


You are correct. There was nothing wrong with the diode.

I checked D12 with a meter and it looks fine. (0.5 Volts)


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## pdove (Jan 9, 2012)

Coulomb said:


> Maybe the charger is also not generating power at all.


I think you are right. It stays in state 0 with he red led blinking and no current. It will adjust the voltage to the battery voltage. 

Sometimes it gets stuck in the rapid flash routine. Usually when I change the battery voltage too low or too high. It flashes the external relay rapidly as well but maybe that is normal.


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## Coulomb (Apr 22, 2009)

pdove said:


> It will adjust the voltage to the battery voltage.


Right. So what I should have said was "Maybe the charger is also not generating _significant_ power at all."



> It flashes the external relay rapidly as well but maybe that is normal.


I assume you mean the externally visible LED. I don't believe that's normal. Perhaps that's telling us that it's rapidly switching between states or something.


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## kennybobby (Aug 10, 2012)

What is the output of the PFC section (Q7,Q8,D1)? Is it held up or collapsed? 

that's in the vicinity of the sparking capacitor, so maybe the FETs are shorted or the diode is open, and no voltage is making it over to the switching FETs of the output side of the central heatsink.

If the control board doesn't measure the expected rectified and PFC'd DC buss voltage on CB pin 11 to pins 8&9, then it is commanding the "500V" in an attempt to get the buss up.

If the output relay is randomly switching, then the battery connected to the output will charge up the caps in the output stage and hold that side up. So you are reading the same voltage on both sides of the relay. i.e. the R10 and the R20 legs, but it is not a real output generated by the switching stage.


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## pdove (Jan 9, 2012)

Not sure I’m following Ken. I measured the voltage at the fets and at the diodes D1 to D4. It measured whatever the battery voltage was and the same as what comes over the serial bus. I had to put it on AC to read the feta. Maybe that voltage was different I don’t remember but there was voltage there. 

What is weird is when I put 150 V battery on there it goes into the rapid flash but when I disconnect the battery it stops the flashing and closes the relay. Then if I connect the battery back it raises the voltage to 150 volts. Strange

Oh, and sometimes when I hook the battery up while the relay is closed the led visible from the outside turns solid red no flashing


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## kennybobby (Aug 10, 2012)

What do you read across the Big Red Jumper pairs, one is the positive DC buss from the PFC stage, the other is the return side. Take a look at the top left and bottom left corners of the HV Output schematic.


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## pdove (Jan 9, 2012)

kennybobby said:


> What do you read across the Big Red Jumper pairs, one is the positive DC buss from the PFC stage, the other is the return side. Take a look at the top left and bottom left corners of the HV Output schematic.



I don't know what you mean but the voltage on CB11 and 9 was 160V. The battery is 128 Volts.


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## kennybobby (Aug 10, 2012)

i'm a bit rusty and puzzled by the 511 V.

Is the float value for the PFC voltage (f_PVC_Vout is: 282.0000) a command set point, or a measurement? 

Have you tried pressing the button to use a different curve? If so does anything change or is the error still the same value?


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## pdove (Jan 9, 2012)

kennybobby said:


> i'm a bit rusty and puzzled by the 511 V.
> 
> Is the float value for the PFC voltage (f_PVC_Vout is: 282.0000) a command set point, or a measurement?
> 
> Have you tried pressing the button to use a different curve? If so does anything change or is the error still the same value?


PFC_VOL_SET establishes a setpoint for the Power Factor Correction "front end" to aim for; this sets the DC bus voltage. If running on 240 V, this set point is 385 V (basically, run flat out), but if the mains is around 120 V, the set point is calculated based on the battery voltage, required power, and a few other factors.(Excerpt from Coulombs post)

PFC_Vout is defined as max_power

I believe these are the same value but I can't tell looking at the code because it is not called f_PVC_Vout in the code. 

I found 512 in the code but I am not sure how it is used.
code:0D32 11 code_D32: .byte 0x11 ; DATA XREF: charge_state_PRO+1Co
code:0D33 44 00 00 00 .byte 0x44, 0, 0, 0 ; FP 512.0


It looks like it sets the output to this in case 0.... for charge state 0

code:0085 csp_case0: ; CODE XREF: charge_state_PRO+12j
code:0085 C2 08 clr bools2.0
code:0087 12 1A B4 lcall RELAY_SET
code:008A 90 0D 32 mov DPTR, #code_D32
code:008D 12 11 A8 lcall code_11A8
code:0090 F6 mov @R0, A
code:0091 78 9C mov R0, #f_AH ; RUN.
code:0093 12 0C 55 lcall StoreFloat_R0


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## pdove (Jan 9, 2012)

Just something I noticed today. There are no jumpers on this daughter board. It is a version 1.4.


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## Coulomb (Apr 22, 2009)

pdove said:


> Just something I noticed today. There are no jumpers on this daughter board. It is a version 1.4.


"Jumpers" is perhaps a bad term. They're just pairs of holes, which can potentially be jumpered. And if course, they're buried under the black gunk.


I can't quickly find a 1.4 board, but I'm 90% sure it will have the jumper holes there.


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## pdove (Jan 9, 2012)

Coulomb said:


> "Jumpers" is perhaps a bad term. They're just pairs of holes, which can potentially be jumpered. And if course, they're buried under the black gunk.
> 
> 
> I can't quickly find a 1.4 board, but I'm 90% sure it will have the jumper holes there.


Well, I took some pictures of the back of the board and compared them to a version 1.7 ..... looks to me that they aren't there. I call them jumpers because the have a J reference designator.


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## pdove (Jan 9, 2012)

photos of the front of the board black partially scraped off


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## Coulomb (Apr 22, 2009)

pdove said:


> ... looks to me that they aren't there.


OK, hard to argue with that evidence. Rev 1.4 control boards must be really old.


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## kennybobby (Aug 10, 2012)

i wonder if wires could be inserted or soldered in some vias to make the same connection that the jumpers produce? 

Maybe scrape off a bit more to identify the chips and pins to compare with the jumper locations of the 1.7 schematic.

Did you replace the sparking capacitor--something is likely failed in the vicinity of the arcing.


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## Coulomb (Apr 22, 2009)

kennybobby said:


> i wonder if wires could be inserted or soldered in some vias to make the same connection that the jumpers produce?


I'd give it a 50% chance. For example, to add J7, does R60 exist? You could probably add it if necessary, but if needed it starts getting a lot of trouble.


J8 looks like it needs no support, and that's an important one (turns off the PFC stage). Maybe add two-pin headers and for this type of board, use a different jumper (an actual traditional jumper). Leave the headers in place for the next repair, though that seems unlikely.


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## pdove (Jan 9, 2012)

Coulomb said:


> I'd give it a 50% chance. For example, to add J7, does R60 exist? You could probably add it if necessary, but if needed it starts getting a lot of trouble.
> 
> 
> J8 looks like it needs no support, and that's an important one (turns off the PFC stage). Maybe add two-pin headers and for this type of board, use a different jumper (an actual traditional jumper). Leave the headers in place for the next repair, though that seems unlikely.


I jumpered across the collector and emitter of U7. No PWM was produced.

I probed the UC3846 PWM chip and the voltages were all low, so I believe this chip is fried somehow. I am going to replace it and see what happens.


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## pdove (Jan 9, 2012)

Coulomb said:


> I'd give it a 50% chance. For example, to add J7, does R60 exist? You could probably add it if necessary, but if needed it starts getting a lot of trouble.
> 
> 
> J8 looks like it needs no support, and that's an important one (turns off the PFC stage). Maybe add two-pin headers and for this type of board, use a different jumper (an actual traditional jumper). Leave the headers in place for the next repair, though that seems unlikely.


I jumpered across the collector and emitter of U7 to force the PWM. Still no pulses. So I probed around on the UC3846 PWM chip. 

Vin = 2.5 V but on the other side of R42 I had 15 V most of the rest were in the milivolts.

I think this chip is fried. I am going to replace it and see what happens.


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## kennybobby (Aug 10, 2012)

Paul and i did some troubleshooting on the charger he is repairing. 

The gate drive output on pin 20 of the PFC chip (U2, 4981A) was zero, just to confirm there was no PFC happening. The Vref was 5V, so the chip seemed to be alive and okay, it just wasn't driving the FETS, Q7&8 on the AC input schematic.

So Paul made some measurements of the input signals such as the AC current (IAC), RMS voltage (VRMS) and feedback voltage (VFEED), and everything seemed to be within normal range. 

Then i wanted to see what the DC current sense (Isense) was reading. This is taken off of the piece of wire on the DC return line on the bottom side of the main board designated as R13. That's when we found a big problem-- the voltage on Con pin 9 was reading 160 VDC when it should only be 10's of mV above ground! And the plated hole thru which the main board screws to the heat sink was also reading 160V! Turns out the X1Y1 safety cap C4 was shorting the +160V to chassis. Yikes this is a really dangerous failure.

With the unit powered off he found that the trace from R13 to Con pin9 was open, so there was no input signal for Isense making it to the PFC chip. That would be a good reason why it was not driving the gates. But finding and following the trace is tough due to all the yellow staking compound.

Paul will be gone out of town for a week or so-- will have more to report after then.


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## pdove (Jan 9, 2012)

kennybobby said:


> Then i wanted to see what the DC current sense (Isense) was reading. This is taken off of the piece of wire on the DC return line on the bottom side of the main board designated as R13. That's when we found a big problem-- the voltage on Con pin 9 was reading 160 VDC when it should only be 10's of mV above ground! And the plated hole thru which the main board screws to the heat sink was also reading 160V! Turns out the X1Y1 safety cap C4 was shorting the +160V to chassis. Yikes this is a really dangerous failure.
> 
> With the unit powered off he found that the trace from R13 to Con pin9 was open, so there was no input signal for Isense making it to the PFC chip. That would be a good reason why it was not driving the gates. But finding and following the trace is tough due to all the yellow staking.


The question remains .... What failure caused the trace to pin 9 to burn.


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## Coulomb (Apr 22, 2009)

pdove said:


> The question remains .... What failure caused the trace to pin 9 to burn.


Yeah. The current may well have gone through pin 9, burning at least part of the PFC chip U2. Strange that it was still able to output 5.0 V on Vref though.


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## kennybobby (Aug 10, 2012)

The little 10 Ohm resistors R107 on pin 5, and R108 on pin 9, were intact, as were all the other resistors in the U2 current sense circuitry.

The sparkling cap was arcing between it's case and the lead of Resistor R15 on the main board AC input schematic (that you found and added). i think that pin 9 trace runs under the cap, so it may have been subject to arcing also. 

And if there was trace metal debris still in the vicinity, then the cap case might be shorting to the remaining trace. The case is connected to neither + or - but can read a charged voltage.

Gonna need to pull the board and remove the caps, then put some eyeballs or camera on what is underneath them.

[edit: note to check continuity between cap case and pin 9 since measurement between pin 9 and R13 was open, and pin 9 was reading 160VDC.]


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## pdove (Jan 9, 2012)

On further investigation.... daughter board pin 9 is supposed to go to right side of the current sense wire so it reads across pins 5 and 9. I get an open on pin 9 so the trace is gone. In addition resistors R8 and R9 are shorted the ones that go to the gates of Q7 and Q8.R6 and R7 still read 10 ohms.

I am not sure the effect this would have on the FETs but is must br raising the Gate current. 

Now it makes sense why it won't ramp the current.


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## kennybobby (Aug 10, 2012)

i thought you looked at the bare control board and it was pin 9 that went to R108..?

On the main board there is a large ground area underneath the big caps with two little traces running to pins 8 and 9 of the control board, these are both "upstream" of the return current sense wire, but only pin 9 runs to the + input of the current op amp inside the PFC chip.


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## pdove (Jan 9, 2012)

kennybobby said:


> i thought you looked at the bare control board and it was pin 9 that went to R108..?
> 
> On the main board there is a large ground area underneath the big caps with two little traces running to pins 8 and 9 of the control board, these are both "upstream" of the return current sense wire, but only pin 9 runs to the + input of the current op amp inside the PFC chip.


You are right I typed the wrong number. I corrected it in my post.

In addition, the insulation on the big red jumper wires is cracked and missing in places.


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## pdove (Jan 9, 2012)

I have TCCH-240-5 1.5kW charger.

When I connect the battery it starts pulling the battery down. I removed the output relay and C14 and it still pulls the battery down. I am struggling with what else could cause this. I would suspect C21 and C13 but the charger is out of the case so the chassis connection is not present. They go to a bolt hole that's not connected. R10 and R2 seem to read fine with a meter. D2 seems to work as well. I also noted that with the charger plugged in and no battery connected I read 2 volts on the output even with the relay and C14 removed. It is just not making sense looking at this schematic.


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## kennybobby (Aug 10, 2012)

Is it a 1.7 version board or something different?


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## pdove (Jan 9, 2012)

kennybobby said:


> Is it a 1.7 version board or something different?


Version 2.0


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## Coulomb (Apr 22, 2009)

pdove said:


> I also noted that with the charger plugged in and no battery connected I read 2 volts on the output even with the relay and C14 removed. It is just not making sense looking at this schematic.


I would not worry about that; it could just be leakage through the MOSFETs. It's also possible it comes from CMPREF on the processor via several resistors and D12.

I'd consider replacing D12 even though it seems to work OK. It's supposed to stop the battery draining.

Is it possible that there is conductive muck on the PCB, perhaps under the output connector? Higher voltage may find a path that a 3 V multimeter does not.


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## pdove (Jan 9, 2012)

Coulomb said:


> I would not worry about that; it could just be leakage through the MOSFETs. It's also possible it comes from CMPREF on the processor via several resistors and D12.
> 
> I'd consider replacing D12 even though it seems to work OK. It's supposed to stop the battery draining.
> 
> Is it possible that there is conductive muck on the PCB, perhaps under the output connector? Higher voltage may find a path that a 3 V multimeter does not.


Turned out to be low or dead cell in the battery. Haven't steps tested the cell yet.


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## Alex A (Apr 16, 2020)

pdove said:


> Turned out to be low or dead cell in the battery. Haven't steps tested the cell yet.


just interested, after checking errors on diagram where was identified problems with connection?


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## dtbaker (Jan 5, 2008)

pdove said:


> Turned out to be low or dead cell in the battery. Haven't steps tested the cell yet.


aha, you mean the pack voltage was not within parameter, charger doesn't 'see' a valid pack voltage, and doesn't start charge?

Thats a trick with these suckers... the final test has to be the charger hooked up to a live pack providing at least minimum voltage set in parameters before they even start up....


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## reedb (Dec 16, 2012)

I have: 



Elcon EV Charger - TCCH-120-15
Alg 521av, 144V2K5W 52CELL

Control board: TCCH1K5W A Ver 1.8


I have a blown control board with a hard (1.2 ohm) short between VCC and DGND. This was caused by a bad simulated battery hookup which fed line voltage back through R39. Removed U3, VCC to DGND still shorted. Powered charger, 12VDC at CON32S pins 22 & 23 is good. Unfortunately I'm not having any luck isolating this short. Do any of the experts here have any ideas? Thanks, -Reed


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## kennybobby (Aug 10, 2012)

*Fuse R39*

On the control board, R39 is actually a Fuse marked "JB" on my board, that connects pin 2 of the 7-pin header (GND) to pin 22 of the control board, DGND.

During this incident did you have any sort of enable circuit connected to the round 7-pin connector on the side of the box?

Did you have any circuit board damage on the Output side of the Main board?


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## reedb (Dec 16, 2012)

I don't remember (it was some time ago). If I did, it would have been just a jumper between pin 1 & 3. I don't see any damage in the output section. 



About that fuse, It didn't appear to blow. It still measures 1.6 ohms.


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## pdove (Jan 9, 2012)

reedb said:


> I have:
> 
> 
> 
> ...







My first guess is that the processor if fried. There may be other parts causing the short. The most common parts to fail are the Opto couplers On pins 6 and 7 of the 7-pin flat connector but they shouldn't cause a short. I have seen D8 D9 D13 and D14 bad before but not usually shorted.I have also seen U6 the LM258 chip bad before.


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## reedb (Dec 16, 2012)

I was afraid of that. I'll try lifting the VCC pin on the processor pin first. It seems that if it's the processor I'm in bad shape. I'd need to get a new processor, a programmer and firmware (I don't have a copy of the firmware). The PCB seems pretty fragile (I had trouble with the voltage regulator pads coming loose). Is there any source of new or used control boards? 



Thanks -Reed


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## kennybobby (Aug 10, 2012)

check the LM20 temperature sensor chip, U11.

It's not clear exactly what happened--you said that line voltage (120vac?) got connected to the charger output? which side of the output, the + or - wire?


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## reedb (Dec 16, 2012)

I was connected to the serial interface through the 7 pin connector to a desktop computer (through the key board USB hub and a USB2Serial cable). I was powering the charger through a small isolation transformer. I was looking at received packets and wanted to see the battery voltage change so I connected a bridge rectifier and cap directly to the line, charged the cap to ~160VDC, disconnected the line then connected that to the battery output on the charger. I did this a couple of times with out a problem, but then forgot to disconnect the cap charger once. DGND is connect to battery ground internally. Blew out the control board, the keyboard and the USB2Serial cable. Didn't destroy the iMac.


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## reedb (Dec 16, 2012)

U5, Phillips P89LPC938FDH was shorted. I got it off without damaging the board. My board has a thick clear coat which makes it hard to work on. I also lifted U11 and U4. U11 I think I can salvage. U4 and U3 I will have to replace. U4 is not on the 2018 May 24 version of the control board schematic. Does anyone have any info on this part? Also any ideas on how to proceed at this point (finding firmware)? Thanks for the help to this point.
-Reed


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## kennybobby (Aug 10, 2012)

U4 is on Paul's eagle schematic of the control board posted in the TCCH schematics thread referenced in the first paragraph of the first post of this (the repair thread). Coulomb has a good schematic index on the first page post#4 of the schematic thread also.

Programming a new chip is possible and Paul has done this several times. It may be described in the TCCH firmware thread, or buried somewhere in this thread--will need to refresh my memory on that.


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## reedb (Dec 16, 2012)

It seems like the firmware links in the Elcon mast link list are broken: 

https://www.diyelectriccar.com/forum...d.php?t=134233
https://www.diyelectriccar.com/forum...ts-134225.html


At this point I'm wondering if there are some quick tests I can make to the rest of the charger to see about its health. I know 12VDC is good. I can power up with ~50VAC and see that the startup relay closes and can measure 12VDC feeding the MCU section of the control board.


Are there some other quick checks I can do with out a working MCU?


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## kennybobby (Aug 10, 2012)

Something goofy going on at the site, links were working yesterday.

Check the status of all the semiconductors, the FETs and diodes on the heatsink. Those can get damaged. Hopefully yours are okay as they are a pain to change.

AC input rectifier, PFC FETs and diodes, switching FETS and diodes, output stage diodes


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## Coulomb (Apr 22, 2009)

reedb said:


> Are there some other quick checks I can do with out a working MCU?


In the index, look for the post about the jumpers. There are several tests you can do, and they don't require the MCU to be working. The last of these has the full bus voltage and the MOSFETs switching.

The firmware topic is here:
https://www.diyelectriccar.com/forums/showthread.php/elcon-tc-charger-firmware-facts-134225.html

If it's not working, I have a backup here:
https://forums.aeva.asn.au/viewtopic.php?t=5618


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## reedb (Dec 16, 2012)

Thanks very much for those links. I think I'll be able to figure it all out from here. Just one more quick question, do you have C source code for the Calibrator.asm file? Thanks, -Reed


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## Coulomb (Apr 22, 2009)

reedb said:


> Thanks very much for those links. I think I'll be able to figure it all out from here. Just one more quick question, do you have C source code for the Calibrator.asm file? Thanks, -Reed


 No. Real men code in assembler 


Well, they (real men) do when they have little choice, and most of the assembler code is already there for them. And when the code isn't all that complex, as in this case.


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## reedb (Dec 16, 2012)

I'm looking for discussion of what kind of signal should be on AD01 and OCA. I'm not sure I see any commands in the calibrator program to monitor/set these. Thanks, -Reed


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## pdove (Jan 9, 2012)

reedb said:


> I'm looking for discussion of what kind of signal should be on AD01 and OCA. I'm not sure I see any commands in the calibrator program to monitor/set these. Thanks, -Reed



Someone may correct me but my understanding is that pin 25, marked AD01, is read into variable AD_PROTECT in the main charger code. 



It is practically digital signal, fed through an opto isolator without any adjustments for Current Transfer Ratio (like gain), or the like.


So every 11th real time clock interrupt, i.e. every 100 ms, this input is checked against fixed thresholds to determine whether the mains is 220 V, 110 V, or low. The name and the speed with which it is checked seems to me to indicate that the PFC stage could be damaged by prolonged operation at the wrong "setting".
Then the resultant uVAC_S is to copied into RUN.VAC_S. RUN.VAC_S is used in PFC_VOL_SET to set the voltage the PFC stage should aim for. If at 220 V, it is set to "wide open throttle" with u=1023; other wise there is a calculation involving the present DC voltage, the turns ration of the transformer (from EEPROM), and a constant called DEF_PULSE_LOSS set at 0.80. This is output to PWM_CHANNEL_A, which has the value 0. I suspect that this sets the duty cycle of OCA (Output Compare A), pin 27, which is smoothed and ends up driving an op amp (U13 pin 8) which drives signal VFEED. This seems to be an important input into the PFC chip, U2.
The tweaking of the thresholds for the PROTECT channel would therefore be a response to problems with the charger not guessing the AC input voltage correctly, presumably under uncommon, adverse conditions (AC voltage very high or very low). 

My understanding is that the Calibrator code is run with AC Input voltage at 50V.


----------



## Coulomb (Apr 22, 2009)

pdove said:


> AD01...
> It is practically digital signal, fed through an opto isolator without any adjustments for Current Transfer Ratio (like gain), or the like.


I would agree with almost digital; I believe that three states are recognized:
a) AC-in < 73 VDC or ~80 VAC
b) AC-in between the above threshold and 150 VDC or ~167 VAC
c) AC-in above the threshold in b).


These would result in very low, medium, and high (nearly Vcc (3.3)) volts respectively at AD01.


OCA would I believe be a square wave with varying duty cycle. When ≥220 VAC is detected, the square wave would have very high duty cycle, perhaps always on (3.3 VDC).


I don't believe that this is terribly critical; it's just a matter of aiming for a bus voltage that can be achieved from the present AC input voltage, and which will result in enough voltage and power to charge the battery without excessive ripple on the DC bus. When 120 VAC is detected, there are lower maximums for charge power and the like.


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## reedb (Dec 16, 2012)

Paul I missed that bit on restricting the input voltage when the Calibrator program is running, thanks for that. 



I think I understand what is going on here now. 



My replacement parts have arrived so I hope to be able to do the jumper tests soon (U1, U7 and U8 are out now). I know that +15VDC and +12VDC are still good. 


Also I have measured all the capacitor values out of circuit in the processor section if any one would like to see them. Thanks, -Reed


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## kennybobby (Aug 10, 2012)

reedb said:


> ...
> Also I have measured all the capacitor values out of circuit in the processor section if any one would like to see them. Thanks, -Reed


Yes thank you, all data helps.


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## pdove (Jan 9, 2012)

reedb said:


> Also I have measured all the capacitor values out of circuit in the processor section if any one would like to see them. Thanks, -Reed





Yes, please. We love data.


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## reedb (Dec 16, 2012)

For the processor section of the control board, TCCH1K5W A Ver 1.8, I read the following capacitor values (out of circuit): 



C7 - 100nF
C8 - 44nF
C9 - 100nF
C10 - 72nF
C11 - 100nF
C12 - 100nF
C13 - 220nF
C14 - 33nF
C15 - 100nF
C16 - 100nF
C17 - 100nF
C18 - 100nF
C19 - 10nF
C20 - 10nF
C21 - 1nF
C22 - 100nF
C23 - 100nF
C24 - 100nF
C25 - 6nF
C47 - 30nF
C48 - 100nF
C64 - 4.7uF
C65 - 80nF



-Reed


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## Coulomb (Apr 22, 2009)

After a particularly gruelling repair, I reassembled the charger for a final test. I plugged everything in, pressed the switch, and ... the house went dark. Dang. The RCD / GFCI had tripped. Maybe I should have let the silicone cure for a bit? I did use that cheap brand, natural cure of course... Back to the bench, and I measured 1.3 MΩ from live or neutral to earth in one direction, and a lot more capacitance than usual in the other direction. OK, so after the bridge, or those two diodes that are used for the PFC chip, but where? I took the cover off again (24 screws), and was surprised to find that the conductivity was gone! I could not coax any conductivity from L to E using the 52 V power supply either.

Was it the cover pressing on something? A screw penetrating? No amount of pressure or prodding would get the fault back. I connected the multimeter to the AC-in L and E, and watched it as I replaced the cover, expecting the fault to return. Nope. I added a few screws... added all the screws... turned upside down... still no fault!

So now it's fixed? I constructed some story in my head about how the silicone hadn't cured, and the cover seals very well, so removing the cover might have suddenly cured the last bit of silicone? So I applied power again, and the lights went out again. Well, at least the fault was back, measurable with the multimeter. I left the multimeter on as I undid those 24 screws carefully, removed the cover carefully... the fault was still there! OK, progress of sorts. Nothing looks amiss. I probe away with one end of the multimeter connected to the chassis, and find that the positive output of the bridge had 1.6 Ω to earth! Well, that would probably do it. The PFC inductor has such low resistance that I couldn't easily tell which side was shorted. Maybe it was the inductor itself? I did notice that the PCB "hat" was at more of an angle than is usually the case. I undid the nut slowly, watching the multimeter... it's gone! It's back! It's ... intermittent.

The inductor wasn't terribly well positioned, and there is that really long metal M3 screw that holds the hat on, which must have rubbed against the enamel of the inductor's wire. I'd say it did so in such a way that it took some voltage to break down the remaining insulation. More than 52 VDC, but 240 VAC was enough. I could not see any worn insulation, but it's pretty hard to see in there. I think that the chances of shorted turns is pretty close to zero. So I added some heat shrink tubing over the screw, applied mains power, and the lights thankfully stayed on. That's the first time I recall coming across that problem.


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## pdove (Jan 9, 2012)

Good to know. Probably should add the heat shrink every time to circumvent this next time.


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## eyup (May 1, 2020)

Hi all
When I first ran into problems with my charger, I searched Google for information about these charges. And of course the only useful information was found only here. For the tremendous work that you all have invested here, a special thank you to all of you.
The first time around, my problem was simple. The contact pad is burnt out into which the output fuse is connected. Then I fixed the issue very easily thanks to this thread.
I have a more serious problem now. Both chargers are out of order and do not want to charge. Looking for a solution, I have read almost the entire thread since 2010. I found a lot of useful information for myself. but also, the more information I received, the more I was convinced that these charges are rather complicated devices. Since yesterday, I stopped trying to repair myself.
I still really hope for information from you that will help me step by step to solve the problem with two charges.
And so, after the prehistory, I can tell you about the features of two charges.
these are the tcch 96v 24A chargers. one of them without CAN and the other in my opinion is the CAN version.
1) first one. Without CAN bus. On the main board, the indicators are off, on the secondary board, the indicators are working and give an error about the lack of communication (R G R G R G R). The fans are spinning. the input relays close and open normally. in pins (22-23) where there should be 12v, there is a voltage of 31v. in pins 1-5 of the black five-pin connector, the voltage is 0v. pins 1-8 have a voltage of 15v. At the output of the rectifier diode d7, the value is 294v. From the visual I drew attention to the resistor R2, which visually has a gray tint on top. But the resistance is working and gives 7.5KoM during measurements. in pins 16-17 also 0v.
Please give me some advice, what should I check next? 
Which part i should to check or remove from board? 
Thank you


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## pdove (Jan 9, 2012)

eyup said:


> 1) first one. Without CAN bus. On the main board, the indicators are off, on the secondary board, the indicators are working and give an error about the lack of communication (R G R G R G R). The fans are spinning. the input relays close and open normally. in pins (22-23) where there should be 12v, there is a voltage of 31v. in pins 1-5 of the black five-pin connector, the voltage is 0v. pins 1-8 have a voltage of 15v. At the output of the rectifier diode d7, the value is 294v. From the visual I drew attention to the resistor R2, which visually has a gray tint on top. But the resistance is working and gives 7.5KoM during measurements. in pins 16-17 also 0v.


If there is 31v on pins 22 and 23 then your viper chip is putting out the wrong voltage it should be 15V. It is on the main board next to the small transformer in your first picture. A small 8 pin chip with a copper heat sink. Also 31v on those pins will most likely fry your Voltage regulator that makes 3.3v for the processor. Pins 1-5 on the black connector should be 3.3V. I will try to post some pictures


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## pdove (Jan 9, 2012)

pdove said:


> If there is 31v on pins 22 and 23 then your viper chip is putting out the wrong voltage it should be 15V. It is on the main board next to the small transformer in your first picture. A small 8 pin chip with a copper heat sink. Also 31v on those pins will most likely fry your Voltage regulator that makes 3.3v for the processor. Pins 1-5 on the black connector should be 3.3V. I will try to post some pictures


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## eyup (May 1, 2020)

Thank you very much for suggestion. İf voltage regulator fried, i need to replace these chips. I could not find it on control board schematic. and it is covered with black material. how i can understand IC code for buying new one?


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## pdove (Jan 9, 2012)

eyup said:


> Thank you very much for suggestion. İf voltage regulator fried, i need to replace these chips. I could not find it on control board schematic. and it is covered with black material. how i can understand IC code for buying new one?


The part numbers are on the schematic. Voltage regulator SSPX-1117M3.


https://www.diyelectriccar.com/attachments/tc15_control_board_mods-sm-jpg.105874/



I would check the output of the viper before replacing the voltage regulator. The viper is on the low voltage supply schematic.








TCCH Elcon 1.5kw charger schematics


This is a project to create troubleshooting and repair schematics for the 240vdc, 5amp version 2.0 board. Pictures and sketches will be added as available. Here is a quick basic overview of the electronics inside the box. The main analog power board is screwed to the heatsink. The big...




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pdf1.alldatasheet.com


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## Coulomb (Apr 22, 2009)

Earlier, I wrote that R3 and C11 are often found under browned yellow gunk, indicating that they got hot. These are snubber components, so they're not essential to getting the circuit working on the bench, rather, they protect components long term and against transients. So they are easy to overlook.

I thought I'd post a picture of where they are, after it took me a long time to find them. The thick wire with the red insulation is actually ground, not the positive end as you might expect from the color. The photo is from a "parts only" charger. R3 is 470Ω, C11 appears to be 47 nF (can't easily be measured in circuit).


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## Coulomb (Apr 22, 2009)

*A and B PWM outputs; the U12 latch*

The way the A and B PWM outputs work on the UC3846N PWM chip isn't well explained in the devices' datasheet; nor is the purpose of U12 obvious. Inside the PWM chip is a toggle flip-flop; it is toggled by the sync pulses between cycles. So this flip-flop has one output high for one cycle, and the other output high for the following cycle. When the output is high, it drives the associated 3-input NOR gate's outputs such that the associated output is low. So in any one cycle, only one of the A or B outputs will pulse high; the other will remain low for the entire cycle. This is intended for push-pull circuits, such as shown in the datasheet as an example use case.

Here we have a full bridge. To adapt these two outputs to a full bridge, the U12 latch is employed. Suppose that the upper gate of the latch is high, i.e. pin 4 is high. This will drive pin 3 low. Pin 4 connects to HIN of U15, the driver for the left side of the full bridge. So the left side of the full bridge is high. Output A is low, ensuring that there is no shoot-through on the left side. As soon as a high pulse appears on the A output, the latch changes state, so that pin 4 goes low and since the B output will be low, pin 3 goes high. It takes about 10 ns for this to happen, so we can't have the LIN go high for a while, plus we need some dead time for the MOSFETs to switch. This delay is provided by R51 and C30 on the left side (R50 and C29 on the right side). After about one time constant, which I think is about 2 μs, the LIN low-side input of U15is high enough to drive the left side of the full bridge low. Now that pin 3 of the latch is high, the right side of the bridge is high, so the transformer primary sees a pulse of current from the right side to the left. At the end of the A output's pulse, the low side transistor switches off, and does so quickly because of D11 shorting R51. The high-side MOSFET stays off however because nothing has caused the latch to change state as yet. So for the rest of this PWM cycle, the left side has both MOSFETs off.

At the beginning of the next cycle, the B output will pulse high, changing the latch state again, turning on the high side transistor on the left side, and pulsing the right side low. This causes the transformer primary to see a pulse of current from the left side to the right side. At the end of the B output's pulse, the right side has both MOSFETs off, while the left side's upper MOSFET remains on.

So at any one time, one of the sides has its high-side MOSFET on, while the other receives a low pulse, followed by both MOSFETs on that other side being open. Thus the transformer sees a pulse of voltage in one direction, followed by a pulse of voltage in the other direction. These pulses are rectified by two of the diodes on the output of the transformer to charge the output capacitors via the output inductor. The wider the pulses at the A and B outputs, the more current is available to charge the battery. Both the A and B output pulses' widths are affected by the current sensing and the error amplifying. In these chargers, the "current sense" inputs are driven by the desaturation protection circuit, and the error amplifier is fed from the difference between the CMP1 output of the processor and the measured current, via opto-coupler U7.

Any asymmetry in output widths during this test (and probably in general) indicates a fault in the desaturation protection circuit.


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## HARDYSOFT (Oct 11, 2015)

I'm just an EV owner. Are these two chargers compatible? The old one is ruined. Can the new one be simply installed in place of the old one?
This connects "ElCon CANbus Interface (Only for ElCon PFC chargers with factory-installed CAN card)" to the CAN bus.























https://www.aliexpress.com/item/1005001857804909.html?spm=a2g0o.productlist.0.0.662d376dTiamwc&algo_pvid=a34dd309-64f8-4005-a5a1-64a6a364b77c&algo_exp_id=a34dd309-64f8-4005-a5a1-64a6a364b77c-0&pdp_ext_f=%7B%22sku_id%22%3A%2212000017880840910%22%7D&pdp_npi=2%40dis%21HUF%21223535.0%21143062.57%21%21%2114405.77%21%21%402101fd4b16675958716492905e843c%2112000017880840910%21sea&curPageLogUid=852ZZJAjpzhJ


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## pdove (Jan 9, 2012)

What is wrong with it? They can be repaired. I don’t know the answer to your question but I can tell you that the Elcon does not have a CAN bus. You need an external device to make the CAN signals that plugs into the front connector


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## HARDYSOFT (Oct 11, 2015)

pdove said:


> What is wrong with it? They can be repaired. I don’t know the answer to your question but I can tell you that the Elvis does not have a CAN bus. You need an external device to make the CAN signals that plugs into the front connector


An expert said it couldn't be fixed. Because the electronic part of the switch did not open.

Maybe just the blue connector should be attached to the control switch of the new device? Would the TC619B pass on the on/off from the CAN?


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## pdove (Jan 9, 2012)

That doesn’t make any sense to me. Is he speaking of the input relay or the output relay? Both can be replaced.


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## Coulomb (Apr 22, 2009)

HARDYSOFT said:


> Maybe just the blue connector should be attached to the control switch of the new device? Would the TC619B pass on the on/off from the CAN?


Charger CAN packets are usually not standardised; you usually can't just replace one with another. Repair would be by far the easiest option. You just need to find someone who actually knows how to repair them.

Having said that, the above new charger does look like an Elcon, albeit the 700 W model, from poor memory. So it might be compatible, but it's far from certain.


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## HARDYSOFT (Oct 11, 2015)

Coulomb said:


> Charger CAN packets are usually not standardised; you usually can't just replace one with another. Repair would be by far the easiest option. You just need to find someone who actually knows how to repair them.
> 
> Having said that, the above new charger does look like an Elcon, albeit the 700 W model, from poor memory. So it might be compatible, but it's far from certain.



I bought an "enable" 1.8KW TC ELCON Charger , (aliexpress) from Deligreencs EV Parts Store,
The ElCon CANbus Interface+ the new TC ELCON Charger, I hope will work.

(I didnt find expert for fixing.)


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## pdove (Jan 9, 2012)

HARDYSOFT said:


> (I didnt find expert for fixing.)


Yes you did but never asked me to fix it


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