# TCCharger Configuration?



## onegreenev (May 18, 2012)

So what information DO you have for your charger? When buying these you need to supply the quantity of cells and AH of the cells and if you had gone through Elcon in Sacramento they would build a profile or use a suitable profile for your needs. Mine is set for 120 volts and 200AH. It shuts down properly every time. I do not have a BMS connected to the charger. Do you? 

Pete


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## TEV (Nov 25, 2011)

Those chargers have a few end voltages programmed ( don't remember the number but is in the manual ) , also in the manual is the procedure to choose the one you want. You should send your serial number to the company and ask for a list with the end voltages.


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## mora (Nov 11, 2009)

Your charger likely has different cutoff points for charge amps instead of different pack voltages. This is because 100Ah and 200Ah cells have different amp readings at the end of charge. 0.05C for 100Ah is 5A but for 200Ah 0.05C is 10A. You might simply have wrong charge program selected for your pack. Charge current should not taper down to zero unless charger isn't operating.

You can ask TCcharger directly what they've programmed to your charger.


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## PeterH (Mar 20, 2009)

Wow, thanks for all the input!

I have my miniBMS controlling the TCCharger to cut off the charge. However, it seems to be acting oddly over the last couple of weeks.

My local EV parts provider took care of ordering the charger and specifying the details with TCCharger. He also sold me my CALB cells so he knew exactly what I needed at the time.

The natural suggestion seems to be to try going back to TCCharger to see what information they have on my charger, based on my serial number. I'll give that a try next. I've not heard of too many people getting the expected response from China latey but I'll give it a try.

Yes, hindsight is still 20/20... I'd have also bought a Warp9 motor rather than the Kostov motor. I'll know better next time for sure!

Thanks,
Pete


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## Yabert (Feb 7, 2010)

Hi Peter

I'm in the same situation than you (Centralized MiniBMS and Elcon charger) and I would like to know more details about the defective bms.
And a question, why you don't asked help to Dimitri from Minibms. It gave me exellent support more than one time.



PeterH said:


> I'd have also bought a Warp9 motor rather than the Kostov motor. I'll know better next time for sure!


Why?


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## PeterH (Mar 20, 2009)

Hi there Yabert,

I'm not 100% certain that the BMS is defective. I've exchanged emails with Dimitri and I owe him a video recording of the end of my charge cycle so he can see how they are behaving.

Here is a pic of my BMS installation.










You can see the terminal strips where everything connects between the BMS and my cells. That is how I can easily monitor individual cell voltages.

For a long time I've let the BMS shut off the charge on its own. That was after I manually monitored most of the first 10 or so charges back in July. Two weeks ago, I finally installed an Arduino driving a display in my dash to show me the temperatures in each of the 5 battery boxes. I was interested in seeing if the temps went up at the end of a charge and that is when I was manually monitoring the cell voltages and found out the system was letting my cells go past 3.65.

Since then, I've been monitoring the end of every charge cycle and the next one will be recorded again so I can post the video. During the last charge my weakest cell went past 3.65 and probably reached 3.75 before I manually terminated the charge. Tonight I'll monitor another charge and won't take the meter off of my weakest cell till the charge is over so I'll know exactly how high it is going.

Does your Elcon connect via a 3 wire connection to the BMS? The TCCharger has a simple enable/disable circuit that the BMS is using to control the charger. I put a simple toggle switch in that line so I can manually open the ciruit between the BMS and the TCCharger to terminate the charge. 

Why would I have bought a Warp9 rather than a Kostov?

Yes, the Kostov probably has more torque and can handle the higher RPM due to the interpoles built into their motor. I doubt I really benefit from those features.

On the down side, their internal rpm sensor design is horrible. My local EV parts vendor installed their sensor while I was overseas, last November and didn't gap the sensor properly. No one thought to check it before everything was installed. So at the moment, I have no tach. I saw loads of conversions using an external sensor on the aux shaft of the Warp 9 for their tach. Wish I had such an easy option. As it is, I'll have to break down the motor to fix the tach sensor, or come up with another way to get a signal. Someone suggested putting two bolts thru the motor's fan blades, 180 degrees apart and using the proper sensor to pick up the signal. Haven't tried that yet. I was laid off the day I returned from EVCON 2012 and don't have a budget for further tweaks of the EV.

I did correspond with they manufacturer of the Kostov and they admitted their tach sensor design was in need of major revisions. 

I also learned that Helwig Brushes doesn't know anything about the Kostov so when it comes time for new brushes, I'll have to hope I can get some from the factory. My local vendor wasn't sure if he could get them or not.

Just an hour ago I reviewed the manual that came with the charger. It mentions charge curves in the lead-acid area of the manual, but doesn't mention anything about different charging algorithms in the Lithium section at all. My charger is programmed for a max of 162 volts and with 45 cells, that means it should shut down at an average of 3.6 volts. Yet I'm sure the pack voltage never gets that high at the end of the charge. But I'll slap another meter on the entire pack during my next charge just to be sure.

Actually, once I have that video recorded, I'll post it here so you can see how my system is behaving. I'd like to think that will be later tonight. 

Thanks,
Pete


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## PeterH (Mar 20, 2009)

I completed another brief charging cycle tonight. I was only about 15 Amp hours low on my pack so it only took 30 minutes to reach end of charge. Unfortunately, I didn't make it back to the garage in time to watch all of the miniBMS circuits slowly go into shunting mode. By the time I got there, all 45 cells were shunting.

That in itself seems odd unless each circuit shunts a variable amount. I thought it was either shunting or not shunting and if that were the case, I'd expect that once all cells reached the shunting mode, then the charge should end because the BMS was trying to shed power from all cells so at that point, there aren't any cells still trying to catch up.

However, guess I'm wrong about that.

In tonights test, the main pack voltage stayed at 157.6 VDC through out the end of the charge and the one cell I was monitoring reached 3.6775 VDC when the BMS shut off the charge.

I guess no matter how many meters you have, you always want one more. I could use one more to check the other cells in the pack while my two meters were clipped to the system monitoring the entire pack and one specific cell.

I'll have to drive to town again tomorrow so I'll try then to get a better video recording of the end of charge behavior.

Pete


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## TEV (Nov 25, 2011)

I find this a while ago , didn't read all so may or may not be what you are looking for :

http://priuschat.com/threads/elcon-charger-end-voltage-and-other-mods.104914/


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## onegreenev (May 18, 2012)

> In tonights test, the main pack voltage stayed at 157.6 VDC through out the end of the charge and the one cell I was monitoring reached 3.6775 VDC


What is wrong with this charge. I see it as being real good actually. That equals 3.506 volts per cell average. Nearly full but not quite. The cell reaching 3.6775 is still quite safe. The cells should be quite safe up into the 3.8 volt range at those low currents as the charge is tapering down. 

Is your BMS allowing the charger to get to the CV portion of the charge cycle? If so your information should be just fine. Your BMS. I'd think if you actually had a balanced top that your BMS would never need to shunt.


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## mora (Nov 11, 2009)

If you have 3.6V boards shunting starts at 3.5V. More current is forwarded to shunt when voltage rises. At 3.6V shunting current is at its max and won't go higher. Cut off point might be something like 3.65 or 3.70V. I hope I got it right, I've asked Dimitri about this years ago. He can confirm all this.


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## mk4gti (May 6, 2011)

Not sure if this will help but I would try "opening" the cell loop while charging -it should stop the charge within 5 seconds. I have a distributed minibms and elcon so it could be a little different logic.


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## Yabert (Feb 7, 2010)

Hey Peter, what about the different length of your sensing wires? Great difference? What is the wire gauge?

Mine are all in the 36''-48'' range of length and they are 18 Awg.
I will try to watch the ending voltage with my board. Maybe I falsely supposed than the my Minibms turn off the charger when first cell hit 3.6v.


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## dimitri (May 16, 2008)

PeterH said:


> In tonights test, the main pack voltage stayed at 157.6 VDC through out the end of the charge and the one cell I was monitoring reached 3.6775 VDC when the BMS shut off the charge.
> 
> Pete


Pete,

your system is working well and there is no danger to your cells. Its working exactly as designed. Initially your pack was not well balanced, that is why your highest cell was tripping BMS before all cells got to shunting phase. Over time your pack got well balanced so all cells shunt at the end together.

The only imperfection in your system is that BMS and charger aren't in sync for ideal CV voltage to minimize shunting phase.

You don't have to fix it, really, but if you can lower your charger's CV point from 162V to 158V then it would stop charging at the bottom end of shunting phase. 

Alternatively, if you can add one more cell to your pack, then your pack voltage will rise slightly and will end up exactly in the sweet spot for your charger's CV point, so no need to reprogram the charger.

Your BMS has 3 spare channels, one of which can be enabled if you decide to add one more cell.


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