# Needed: CellLog8s Relay Circuit



## major (Apr 4, 2008)

major said:


> I need some help. I know I have seen a diagram of the circuit needed to connect multiple CellLog8s devices to a common relay to interface with the charger on LVC and the vehicle controller on HVC. I have searched, but even the post I think might have had it, the photo link no longer works. I also used google and endless sphere searches to no avail.


O.K. I found these.



















Has anybody tried these? Any other comments or help appreciated


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## honn1002 (Nov 26, 2008)

major said:


> O.K. I found these.
> Has anybody tried these? Any other comments or help appreciated


The bottom wiring diagram is from my old post. Here is the updated wiring diagram for 44 cells. I have been using it about 6 months. It's very reliable. Just plug in to charge and forget about it. No worries about overcharging on any cells. The same way as for driving, the LVC will kick in when any one of the cells hits a set low voltage limit. It reduces the power to 50% throttle. Here is a link to my car in the garage 
http://www.diyelectriccar.com/garage/cars/281

Here is another post http://www.diyelectriccar.com/forums/showthread.php/bms-not-bms-53768p7.html


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## major (Apr 4, 2008)

honn1002 said:


> The bottom wiring diagram is from my old post. Here is the updated wiring diagram for 44 cells. I have been using it about 6 months. It's very reliable. Just plug in to charge and forget about it. No worries about overcharging on any cells. The same way as for driving, the LVC will kick in when any one of the cells hits a set low voltage limit. It reduces the power to 50% throttle. Here is a link to my car in the garage
> http://www.diyelectriccar.com/garage/cars/281


Thanks, honn.


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## spdas (Nov 28, 2009)

Major, did you ever build one? I am looking to build/get someone to build one for me. Honn any updates or comments on your design? 
thanks
Francis


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## Jimdear2 (Oct 12, 2008)

Major,

We are using a modified version of Honn's circuit on our pulling tractor. 

We do not use the HVC protection circuit because our charging system is unable to charge any individual cell stack above 3.5 volts. For the LVC we decided to go with complete shutdown rather than a partial throttle signal he used. We may change that to something other then 50% first we need to see if we will get any cells pulled down to under 2.1 volts during a pull. If we start seeing LVC we plan to try various percentage cutbacks. 

This setup, now that we have it working, is wonderful. We can see at a glance how all 50 cell stacks of the battery are doing while charging and know when all 50 cell stack charger boards have reached 3.5 volts. It also shows us any cell stack imbalance after a pull which might indicate a weak cell in a stack. Another unintended benefit has been the ability to spot a bad charger board (the DC to DC boards we are using are incredibly moisture sensitive and go bad often) before it damages a cell stack.

The system was a bit of a pain to get up and running because of our (my) design/material choices. I used a male/female SCSI cable to wire the Cell Logs to our battery. The cable was cut in half and the ends plugged together. One end of each wire (by color code) went to the individual battery parallel stack, the other went to the mapped Cell Log pin. The system is turned on and off by simply unplugging the male/female cable connectors.

The two difficulties with this set up was my choice to build up the Cell Log plugs myself. The 26 gauge wire used in the SCSI cable is just not tough enough to stand much flexing so even using the correct crimping tools I was having problems with wire breakage when handling the plugs. The other problem was bad (high resistance) in some of the SCSI cable circuits that required replacing some wires.

We will be rewiring the tractor over the winter and we plan to clean up the installation using perfboard, phoenix connectors and some pre made connectors for the Cell Logs I found on eBay. 

Hope this info helps
Jim


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## major (Apr 4, 2008)

spdas said:


> Major, did you ever build one? I am looking to build/get someone to build one for me. Honn any updates or comments on your design?


Believe it or not, we're still working on it. We have tested the circuit boards on charge and discharge and they look good. Hopefully next week we can actually test with them turning off the charger.


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## major (Apr 4, 2008)

Jimdear2 said:


> We will be rewiring the tractor over the winter and we plan to clean up the installation using perfboard, phoenix connectors and some pre made connectors for the Cell Logs I found on eBay.


Hi Jim,

I used #22 wire and MiniFit Jr connectors. Maybe a bit bulky, but durable and I hate working with real small stuff. So eBay beat my connector deal?

Regards,

major


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## Jimdear2 (Oct 12, 2008)

major said:


> Hi Jim,
> 
> I used #22 wire and MiniFit Jr connectors. Maybe a bit bulky, but durable and I hate working with real small stuff. So eBay beat my connector deal?
> 
> ...


Major,

Yah I agree making up those connectors was a MAJOR (pun intended) pain.  I'm in my late 60s so my eyes and dexterity aren't what they used to be.

The connectors I found use 20 AWG silicone wire with about 1 foot of wire lead. At $4.50 each they are hard to beat. 

http://www.ebay.com/itm/130419112764?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

<EDIT>

There are also these with 24AWG PVC wire at $3.79 each

http://www.ebay.com/itm/150608613045?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

<End EDIT>

They come from China so there is a long lead time. 

I plan to use the plugs and leads from the Cell Logs to one side of a barrier strip and the SCSI cable leads to the other side or I might use Phoenix connectors with both wires under the screw.

I could swear that I sent you a post about them.


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## honn1002 (Nov 26, 2008)

spdas said:


> Major, did you ever build one? I am looking to build/get someone to build one for me. Honn any updates or comments on your design?
> thanks
> Francis


Here is my updated wiring diagram. I added a solid state relay to completely turn off the charger, especially the cooling fans that run off the AC. My battery monitoring system using celllogs has been reliable. Currently I have 26,500 electric miles. I never overcharge any of my cells. Just plug in and walk away. I used a small ac-dc converter connected to the charger's AC wires to automatically power my celllogs and the charger external relays. I used two direction diodes to isolate the +12V aux source (from key switch) and +12V ac-dc source for powering the celllogs. See pictures in my diygarage. 

Brian has designed a PCB for the celllog to make the wiring less headaches. Check out his blog for more info. http://s2kev.blogspot.com/


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## frodus (Apr 12, 2008)

those long wires won't allow accurate voltage readings....

[edit]
I know lead length doesn't effect the measurement, but some people have had issues with accurate readings on these cell-logs....whether that was noise, capacitance, etc, I'm not sure, but it should be considered.


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## spdas (Nov 28, 2009)

frodus said:


> those long wires won't allow accurate voltage readings....


I was getting things together to make this cellog setup. So 6' runs of 26 gauge wire (25pr telephone wire) will throw off the reading enough to make the setup not worth it? 

francis


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## rwaudio (May 22, 2008)

frodus said:


> those long wires won't allow accurate voltage readings....


Voltage drop is a function of current, if they are simply voltage sensing wires there is no problem, if you are using wires that carry charging current then as frodus stated it won't work very well.


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## honn1002 (Nov 26, 2008)

frodus said:


> those long wires won't allow accurate voltage readings....


Why not? There is very little current flows through those celllogs wires. What causes the celllog voltage reading appears to be lowered than usual is the external resistance in the high power connections like 2/O gauge wire. For example, during high current load if a 2/O gauge wire connected between two cells is too long, you will notice the voltage reading on one cell is slightly lower. I found this out by swapping the cells. The voltage reading varies depending on the current draw under load. 

Honn


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## frodus (Apr 12, 2008)

No, it's low current I know that, but I know people on ES have issues with long cables and inaccurate readings. Maybe has something to do with some noise? 

can someone test this? I mean, compare his reading at the cell to the reading back at his cell-log?


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## tomofreno (Mar 3, 2009)

I haven't used them with leads longer than about 12" but they always agreed with my Extech 830 dvm - they only read to 2 decimal places though.


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## Jimdear2 (Oct 12, 2008)

As mentioned by others in a couple of posts we also had some trouble at first with inaccurate readings. In the end it appears that the problems were the harness wires themselves. We used a six foot 68 pin (34 pairs) SCSI cable with a male and female plug. We plugged the two ends together and cut the cable into the lengths we needed. One half was affixed to the battery and the other to the tractor, cellog8s and control relay. Since the battery was made to be removable we use the plugs as a means to turn the cellog8s off and to allow battery removal without major wire rework.

At the battery end we connected each wire to a dedicated phoenix connector on the charger boards and noted the color code of the wire and the battery stack number (one through fifty), At the other end I initially built plugs for the cellog8s using plugs and terminals. Although I did have the correct crimping tool it still became a real problem because the wires themselves were not able to withstand all of the mechanical stress while building and installing the plugs. I later found the pre made plugs I noted in a previous post and used them to replace the plugs I built. We still had a few problems that were corrected by switching to a different wire. Since we finally got all of the cellog8s up and reading we find them to be quite accurate within +- 0.002 volts compared to two very accurate VOMs.

So yes, you may get some funny readings at first, but with a bit of care and detailed diagnosis you should be able to get good accurate results. We still don't know why some wires would give an erroneous reading and others would be OK. I'll do some checking this winter when we take everything apart for painting and rewiring.


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## spdas (Nov 28, 2009)

Good morning all. Ok I am starting to build it. I have the cellogs and pre-made cellog wiring connectors and have ordered the alarm relays. But what is the part number for the three on/off DPDT cellog relays? Is this it:

http://www.ebay.com/itm/Tyco-V23079...913?pt=LH_DefaultDomain_0&hash=item256782afe9

And everything else I can get at Radio shack or should I ebay for more of the components? 

thanks
francis


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## T1 Terry (Jan 29, 2011)

Does anyone have the link to the modifiction to the cell log 8 to make it power off all 8 cells rather than the first 6 cells? We are using 2 loggers on a 24v pack in a motorhome, one for LVC and the other for HVC, suprising just how much they put the pack out of balance. We have resorted to readding 4 cells from each logger and not having an LVC till we can get it sorted. 

Thanks
T1 Terry


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## honn1002 (Nov 26, 2008)

spdas said:


> Good morning all. Ok I am starting to build it. I have the cellogs and pre-made cellog wiring connectors and have ordered the alarm relays. But what is the part number for the three on/off DPDT cellog relays? Is this it:
> 
> http://www.ebay.com/itm/Tyco-V23079...913?pt=LH_DefaultDomain_0&hash=item256782afe9
> 
> ...


Francis, 

Yep, that is the same relay brand and part number I used to turn ON/OFf the celllogs.


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## honn1002 (Nov 26, 2008)

T1 Terry said:


> Does anyone have the link to the modifiction to the cell log 8 to make it power off all 8 cells rather than the first 6 cells? We are using 2 loggers on a 24v pack in a motorhome, one for LVC and the other for HVC, suprising just how much they put the pack out of balance. We have resorted to readding 4 cells from each logger and not having an LVC till we can get it sorted.
> 
> Thanks
> T1 Terry


I have a couple pictures show the mod.


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## spdas (Nov 28, 2009)

So, as I understand it, the cellogs do not turn off #7and 8 with the relay on the cellog PC board you made, unless u do this jumper?

Also, I guess my relays coming from China will take 3 weeks or so, but can I make the rest of the board and use it without the alarm relays and just power on via a toggle switch until the parts come in?


thanks. 
Francis


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## major (Apr 4, 2008)

spdas said:


> So, as I understand it, the cellogs do not turn off #7and 8 with the relay on the cellog PC board you made, unless u do this jumper?


No. The CellLog8s draws the power it needs from only the first 6 cells. Although it can operate with fewer than 6. But if you have 7 or 8 cells connected to the CellLog, then cell 7 (and 8) do not contribute current to keep the CellLog lit up. Even though it is only a few milliamps, cell 7 (and 8) will tend to drift higher in voltage than the first 6 cells over long periods (days or weeks).

This is why I disconnect the CellLogers when I am not using them on my 7 cell applications. Opening the most negative connection with a switch or relay will also turn off the CellLoger and mitigate this. 

I just yesterday bled down cells 7 and 14 in my Kokam pack. They had gotten about 50-70 mV high. I am about to try the jumper modification myself. On the 12 cell batteries I use, no problem as each CellLog is just for 6 cells.

That is my understanding.

major


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## spdas (Nov 28, 2009)

To cut to the chase, setting up this cellog8 system is actually a 
B-Monitoring-S. Using and observing Per cell HVC/LVC control with Alarm for the operator to take action. Add to that, intervention on the OP to raise or lower the cell voltage as needed on top or bottom. And carrying in your EV a good jumper to bypass a cell if it goes ballistic or you are forced to limp home and you see a low cell. What more is needed??

francis


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## T1 Terry (Jan 29, 2011)

honn1002 said:


> I have a couple pictures show the mod.


 Thnks for that, looks simple enough that maybe even I could do it, if I can keep the shakes under control

T1 Terry


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## Otmar (Dec 4, 2008)

honn1002 said:


> I have a couple pictures show the mod.


I would suggest that people do not do only this mod and run 8 cells. I've been wondering why they did not connect this from the factory? So I reverse engineered the power supply circuit to find out.

The 3V loads on my non-logging model are 8.8mA peak and 4.4mA with the backlight off. This power is controlled by a B817-40W NPN transistor whose base is tied to the top of a 431 Zener. The Zener takes it's control voltage from a resistor divider on the emitter of the NPN. There is a 2K pullup resistor on the top of the 431 that provides base current to the NPN and keeps the 431 running. The trouble arises with the power dissipation of that resistor and or the transistor. 

If you assume your max worst case cell voltage is 4.2V then I figure that resistor dissipation is .233W for 6 cells at 25.2V and .45W for 8 cells at 33.6V. This is a 1206 resistor which is commonly rated 1/4W and can also be found in 1/2W for a lot more money. Those ratings are on a cold day so normal practice is to halve the rating. I tested mine at 25V input and the resistor got hot, but not too hot. Putting in that jumper can double the heat produced and I think it would fail before long. It could also start a fire and that would not be good. 

Overall I think the listed spec of 43V is quite optimistic! 

I've been wondering how to work around this and I think that if we replace R37 with a 1/2W 4.7K ohm resistor it may survive and allow running off 8 cells. In that case I calculate that at a 8 cell max input voltage of 33.6V the resistor would dissipate .191W and the transistor would take .08W which should be safe. I will add 10 of the 541-4.70KUCT-ND on my next digikey order and report back when I've tested it.


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## major (Apr 4, 2008)

Otmar said:


> I would suggest that people do not do only this mod and run 8 cells.


I never did the modification. Procrastination. I did hear that a fellow did this mod and his 8s model would no longer communicate via the USB.

It'll be interesting to see what Otmar comes up with


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## swoozle (Nov 13, 2011)

major said:


> I never did the modification. Procrastination. I did hear that a fellow did this mod and his 8s model would no longer communicate via the USB.
> 
> It'll be interesting to see what Otmar comes up with


I did the jumper mod and have to attach a 3-cell pack (small cells) to the cell logs to get them to talk via usb. They are no longer happy with just usb power.

I also remember seeing a post (or maybe they sent it to me in email?) by the manufacturer where they describe another mod to reduce the power usage for cellogs that have had the jumper mod done. It involved changing a resistor. I would not be surprised if that addresses Otmar's discovery. I'll dig it up.


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## swoozle (Nov 13, 2011)

Here we go:

The original Junsi direction was to jumper the pads with 0-100R resistor.

"Any value ranges from 0 to 100 ohms is OK, as there is no strict request.
It's related to voltage regulation power consumption issue. Now it's used for 8s, but before this it is used for 6s*4.2V, then it short down 3V. If add the resistor, it will be 8s*4.2V. However, we have not thought about the battery non-balance problem. Later, we will improve it in our next version.
Regards,
Junsi "
http://www.rcgroups.com/forums/showpost.php?p=13429978&postcount=137


Then they mention changing another resistor (looks like the one you refer to) to reduce power usage:
"The red circle in attached pics-- 202 resistor is 2k, if you measure 7s pack, you can replace it to 10k, which would decrease the power consumption."

http://www.rcgroups.com/forums/showpost.php?p=13452879&postcount=143








Otmar, does this address the overheating danger sufficiently?


Oh, and look at this:
http://ev-power.com.au/webstore/index.php/instrumentation/junsi-cell-log-8s.html


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## T1 Terry (Jan 29, 2011)

After we had dramas with a cell logger no longer recording properly we ditched the idea of the bridge. As the difference in current draw is so small we figured a once a year balance would sort the issues if they came up, they haven't after 18mths. Maybe on small cells on a push bike conversion but not on the larger capacity cells anyway, 7 & 8 are rarely the cells that go high at the end of charge, it seems to be a random thing really. We use the logger alarm port to trigger a timer to stop charging for 5 mins or switch a load on for 2 mins greater than the charging amps if a cell goes over 3.6v, they have self balanced ever since.

T1 Terry


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## Otmar (Dec 4, 2008)

swoozle said:


> Then they mention changing another resistor (looks like the one you refer to) to reduce power usage:
> "The red circle in attached pics-- 202 resistor is 2k, if you measure 7s pack, you can replace it to 10k, which would decrease the power consumption."
> 
> http://www.rcgroups.com/forums/showpost.php?p=13452879&postcount=143
> ...



Thanks for those links! Now I'll get nothing done today due to reading all the forums! 

I'm concerned about the 10K for R37 and here is why: 
At 33.6V input, R37 drops 30V for 3mA and .09W heat. That's fine. 
But then the Q6 the B817-40W has to carry the rest of the heat load. 
Max current draw is 8.8 mA, R37 provides 3 of those leaving 5.8 mA for Q6 to dissipate at 30V of drop. 
30V * 5.8mA = .174 W. The internal silicon temperature is rated to rise 625 deg C above ambient per watt. So we multiply .174W * 625 and get 109 deg C of temp rise. 
Theoretically if the air in the unit is under 40 degrees C (104F) then the transistor should not blow up right away, but in my book that's way too hot to be reliable!

My suggestion of using a 4.7K 1/2 Watt rated resistor moves more of the unavoidable heat into the resistor. 30V at 4.7K = .191W. and less into Q6 30V at 2.4 mA = .072W for a temp rise of 45 degrees C which is probably ok. There still is the possible problem that the heat from the resistor will heat up the transistor due to proximity and that's why I intend to test it on the bench. A good rule of thumb is that if you can hold your finger on it for ten seconds without it being so hot that you have to pull away then the part is not too hot. I'm not sure the resistor will pass that test, but we'll see.


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## honn1002 (Nov 26, 2008)

Otmar said:


> I would suggest that people do not do only this mod and run 8 cells. I've been wondering why they did not connect this from the factory? So I reverse engineered the power supply circuit to find out.
> 
> The 3V loads on my non-logging model are 8.8mA peak and 4.4mA with the backlight off. This power is controlled by a B817-40W NPN transistor whose base is tied to the top of a 431 Zener. The Zener takes it's control voltage from a resistor divider on the emitter of the NPN. There is a 2K pullup resistor on the top of the 431 that provides base current to the NPN and keeps the 431 running. The trouble arises with the power dissipation of that resistor and or the transistor.
> 
> ...


I did this jumper wire mod on 6 celllogs. They have been operating over 2 years with no thermal issues.


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## Otmar (Dec 4, 2008)

honn1002 said:


> I did this jumper wire mod on 6 celllogs. They have been operating over 2 years with no thermal issues.


That's great to hear! 
I assume you are running them on 8 cells. 
Can you tell me what the max charge voltage you use per cell? 
I have the resistors and plan to do some testing soon.


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## honn1002 (Nov 26, 2008)

Otmar said:


> That's great to hear!
> I assume you are running them on 8 cells.
> Can you tell me what the max charge voltage you use per cell?
> I have the resistors and plan to do some testing soon.


I set the HVC per cell to 3.6V. The average voltage for 8 cells is ~28V as when one of the cells goes to 3.6V, the charger is turned off. The voltages on 8 cells vary between 3.40 and 3.6V.

Honn


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## Otmar (Dec 4, 2008)

honn1002 said:


> I set the HVC per cell to 3.6V. The average voltage for 8 cells is ~28V as when one of the cells goes to 3.6V, the charger is turned off. The voltages on 8 cells vary between 3.45 and 3.6V.
> 
> Honn


That sounds good and very reasonable. I'm glad to hear that it works well for you. 

So your top of charge is under 28V which is better than the worst case 33.6V that I used for the power calcs. 
I see also that you turn them off when you are not charging or driving, that sure helps the safety and reliability concerns a lot. If your backlight is dimmed while charging then that reduces the load further and I would guess you are in a safe range of power dissipation. 

I was calculating for worst case 4.2V overcharge and hot weather with full backlight on. But that's what engineers do, try to be very careful and plan on worst case conditions all the time. I'm helping design this setup for a friend, what I do on my own cars, well maybe I don't want to talk about that!


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## honn1002 (Nov 26, 2008)

Here is a link to youtube. In this video I set the HVC per cell to 3.65V. 
http://www.youtube.com/watch?v=QY8D-PFX__o

I have put over 60K miles on my electric Civic. 
https://secure.mr2ev.com/evclub/evlist.php?sid=402f79b4b47865f824359cafbdd9516e

Honn


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## honn1002 (Nov 26, 2008)

Otmar said:


> That sounds good and very reasonable. I'm glad to hear that it works well for you.
> 
> So your top of charge is under 28V which is better than the worst case 33.6V that I used for the power calcs.
> I see also that you turn them off when you are not charging or driving, that sure helps the safety and reliability concerns a lot. If your backlight is dimmed while charging then that reduces the load further and I would guess you are in a safe range of power dissipation.
> ...


Yes, I set the backlight to turn off after 70 mins. This may help a lot.


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## Otmar (Dec 4, 2008)

Otmar said:


> My suggestion of using a 4.7K 1/2 Watt rated resistor
> ......I'm not sure the resistor will pass that test, but we'll see.


It has now been tested, but rather than try to keep two threads running I'm posting the results in the endless-sphere forum, you can see my results here: 
http://endless-sphere.com/forums/viewtopic.php?f=14&t=20142&p=682228#p682228


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## DanGT86 (Jan 1, 2011)

I have a couple of noob style questions about the setup in Honn's diagram. I am wanting to basically duplicate it on my 16s 10ah headway pack. I have a basic understanding of the diagram but am curious about how the cells behave when they hit the HVC and stop the charge.

If a cell hits the HVC value, triggers the alarm and shuts off the charger, is there any advantage to using a timer and restarting the chage? 

Would that help bring up the other cells at all or will that just re-trigger the alarm right away?

If non latching relays were used would the relay and charger oscillate at the hvc point or do cells maintain enough surface charge to keep the CL8 alarm active and charger off for a few minutes?

If I understand Honn's setup correctly, using latching relays once its off its off?

The charger I am using has a bulk HVC at 58.4v (3.65v per cell) so I was thinking I would use the Cell log as a safe guard and set the alarm slightly higher. If I find the charge terminated by the CL8 alarm I will know its time to balance with my 8s RC charger.

Also as far as the CL8 8cell power mod is concerned, Could a few LEDs or other resistive loads be used across cells 7 and 8 when the cell log is on to keep the cells more in balance?

Thanks for any info. Its my first LiFePO4 adventure. I planned on having Cell logs anyway as a learning tool and this seems like a great alternative to a full BMS.


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## honn1002 (Nov 26, 2008)

"I have a couple of noob style questions about the setup in Honn's diagram. I am wanting to basically duplicate it on my 16s 10ah headway pack. I have a basic understanding of the diagram but am curious about how the cells behave when they hit the HVC and stop the charge."

"If a cell hits the HVC value, triggers the alarm and shuts off the charger, is there any advantage to using a timer and restarting the chage?"

No need to use a timer to restart the charger. Why to restart the charger, you don't want to overcharge your batteries. They are near full even though not all of them reach the set HVC. 

"Would that help bring up the other cells at all or will that just re-trigger the alarm right away?"

Nope. There is no balancing going on. If you manually balanced your cells, they should be very close to each other in capacity even though their voltages are different at the top end.

"If non latching relays were used would the relay and charger oscillate at the hvc point or do cells maintain enough surface charge to keep the CL8 alarm active and charger off for a few minutes?"

Yes, the relay would turn off and on (cycle) the charger. In this event your charger may not be happy.

"If I understand Honn's setup correctly, using latching relays once its off its off?"

Yes.

The charger I am using has a bulk HVC at 58.4v (3.65v per cell) so I was thinking I would use the Cell log as a safe guard and set the alarm slightly higher. If I find the charge terminated by the CL8 alarm I will know its time to balance with my 8s RC charger.

"Also as far as the CL8 8cell power mod is concerned, Could a few LEDs or other resistive loads be used across cells 7 and 8 when the cell log is on to keep the cells more in balance?"

Once you made the jumper mod, all 8 cells will draw the same power. No need to add additional resistive load to undue the mod.

"Thanks for any info. Its my first LiFePO4 adventure. I planned on having Cell logs anyway as a learning tool and this seems like a great alternative to a full BMS." 

Good luck


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## swoozle (Nov 13, 2011)

honn1002 said:


> Once you made the jumper mod, all 8 cells will draw the same power. No need to add additional resistive load to undue the mod.


Apparently that is debatable. There's mention of non-symmetric continued low level current draw in that endless sphere thread that Otmar referenced and I recall seeing that assertion awhile back in the manufacturer's thread too.


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