Chargery Issues

[RobRoy]

You are being "gentle" and no that should be fine. Again, Passive Balancing really isn't good for bigger cells. I see that similar bounce as well but it's not severe as it is occurring while balancing but I have Active balancers doing that. I trod down the path of the passive balancers starting with one understanding and learning the difference.

BTW I can tell you this, the bulk cells I have do start the nutiness right around 3.400vpc (27.2) but not seriously till above 3.45 (27.6). The matched cells pack doesn't flinch till 3.5 (28v).

Dumb question maybe but I do not see you mention it. Have you ever just swapped the BMS' between you two packs ? if they both do it on the same battery pack well... that would answer questions.

I was taught that a dumb question doesn't exist, embarrassing maybe.
Snooblers suggestion dropping the charge voltage to 27.4 seems to help, at least stopped charging before exceeding the 300mv diff.

I have swapped the lcd panel first and that went batsit crazy - soc changed from 60% to 95% and the balancing issue appeared on both, so they were put back. Right now they seem to be working okay after a big discharge. If the problem continues, swapping them is priority.

If what I'm seeing was present in both units I could understand enhancing its performance. But I have one working good enough to use and one that is quickly becoming unruly. The only way to lower the diff voltage is to discharge and chucking watts (a really big dude) out the window in the dead of winter is not an option for me.

Based on what I see, I don't think its an issue naughty cells, its an issue of constantantly and consistantly keeping them in line.

 

[RobRoy]

The heatsink is on the bottom of the main board. This means a lot of heat goes "through" the board. Turn the main unit up side down. This will help the heat escape without going through the board. Add a low speed PC fan as I did and the overheat condition went away.( unfortunately there were BMS voltage problems causing imbalance in the cells) when the BMS failed, I went a different direction.

Right on Grizzman but there is no turning these boards upside down. Taking your advice as I noticed them getting fairly warm yesterday. Hoping they produce more of that heat in the winter to keep the container from getting to cold

 

[grizzzman]

I'm saying just flipping the whole main box not the board inside.

 

[Steve_S]

OK... Your description of what happened would tell me they have two different Firmware Versions.
The LCD Module is NOT the brains, it's just the UI. Swapping that only accomplishes nothing. Although it shows they are different versions so, you should update the firmware, there were some issues that were resolved "fluttering reading was one".
Current Version is 4.05 for Main Unit & 4.03 for LCD Display.

chargery power, download product specification or user manual of charger,balance, adapter for R/C model

Word of Caution (reminder it is in the manual) never allow any wire (neg or pos) to contact any part of the BMS casings.

 

[RobRoy]

@Steve_S @grizzzman @snoobler
Follow up - Swapped the Bms modules this morning - problem did not follow. Started checking wiring and found the terminal screws loose at the shunt. Tightening them immediately lowered the diff voltage, balanced the charge amps and fixed the balance issue. I checked the battery terminals and found one not very tight - this corrected the erratic bounce I was seeing and also seems to stabilize that cells voltage - the same cell that was peaking first.
I'm confident that I now have a happy system but will watch the high end today. Thanks for your help, input, comments and suggestions.

Grizzzman - you have taught me to first check wiring and connections. Thank you

 

[RobRoy]

OK... Your description of what happened would tell me they have two different Firmware Versions.
The LCD Module is NOT the brains, it's just the UI. Swapping that only accomplishes nothing. Although it shows they are different versions so, you should update the firmware, there were some issues that were resolved "fluttering reading was one".
Current Version is 4.05 for Main Unit & 4.03 for LCD Display.

chargery power, download product specification or user manual of charger,balance, adapter for R/C model

Word of Caution (reminder it is in the manual) never allow any wire (neg or pos) to contact any part of the BMS casings.

Yes I noticed that. I was on Chargery website and saw the 4.05 update. My update is 4.04 on both of them. I have yet to hook up the wifi but now that the problem is resolved its gaining importance. I was aware of the contact issue. Thank you

 

[RobRoy]

I'm saying just flipping the whole main box not the board inside.

understand. My installation makes that an impossible task without a rewiring. I find it surprisingly odd that the module has no legs to cool the underside. I had mine on a foam pad, which is now gone and the box propped up to get air under it.

 

[Steve_S]

Yes I noticed that. I was on Chargery website and saw the 4.05 update. My update is 4.04 on both of them. I have yet to hook up the wifi but now that the problem is resolved its gaining importance. I was aware of the contact issue. Thank you

Like I said in post in Post #5. Wiring connections are often a problem that creates many issues, as you just verified as well. Glad you got it all sorted and running.