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Battery unbalancing

Remember it was applying two amps to the entire battery bank of 96 cells, so if it was discharging 0.1 amps on the peak cells they should have been dropping (right?) even with the two amps of charging because those two amps were distributed across the entire bank, but they weren't they were going up. Now that it's in standby the top cell is dropping like a rock and the bottom cell is barely moving.
 
trig2 said:
Well I certainly do not know what is going on inside this thing but I didn't seem to get any balancing until it had no input or output.
Click to expand...
Overvoltage cell shutdown is a different criterion. It should enable balancing dump even if battery is disconnected from charger or load. If BMS does not bleed an overvoltage cell during overvoltage charging cutoff it could take hours for the BMS to reset charge disabled.
 
It's been a little over an hour and this is the progress it's made.
 

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trig2 said:
Remember it was applying two amps to the entire battery bank of 96 cells, so if it was discharging 0.1 amps on the peak cells they should have been dropping (right?) even with the two amps of charging because those two amps were distributed across the entire bank, but they weren't they were going up. Now that it's in standby the top cell is dropping like a rock and the bottom cell is barely moving.
Click to expand...
If you have 2 amps of charging and 0.1 amps of balance bleed you still have 1.9 amps of charging on cell.

When balancing starts at 3.4v, it starts a race to balance all cells before one of them reaches overvoltage shutdown. The greater the charging current, the more likely it is to lose the race.
 
RCinFLA said:
If you have 2 amps of charging and 0.1 amps of balance bleed you still have 1.9 amps of charging on cell.
Click to expand...
I don't think that's correct, consider 2 amps = 110 watts at 55v. Those watts should be evenly distributed over every cell in the bank. 110/96=1.14 watts per cell. The balancer appears to discharge five watts per cell. Should have been a net drain on the cells that were being balanced of about four watts. Yes the bank as a whole would go up but the top cells should be dropping if it's balancing.
 
Looks like the 5 watts was just inverter idle draw when I had it on grid mode?‍♂️ At least it seems to be balancing one way or another now.
1682978439025.png
 
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