New 48V battery, potential issue

[Samcat]

You can also increase bms high cell to 3.500 V but set Inverter to never reach this cell voltage ( pack Voltage 55.200 V )
That will be 3.450 V per cell. 3.370- 3.400 with absorption should be your cell target Voltage. Also need to check Voltage drift from charger to the pack terminal ( before bms not after BMS) to adjust. This should be done while charging at various different current ratings. You will need quality voltmeter and if possible calibrated for fine tuning and Voltage drops between battery terminals and charger.

 

[dpappyp]

Thanks for input, Samcat. My inverter settings were more conservative than the BMS (goal being to have the battery capture solar energy when the loads didn’t fully utilize the available solar, but still have available capacity in a power outage and extend life). Back to grid was set at max allowed 51V and back to discharge at 53-54V. Before I had done any kind of balance on the pack the BMS was recording events when voltages were getting outside limits. After I balanced the pack the BMS was still cutting out with no abnormal events recorded and I was nearby to confirm there was no valid reason for the cutting of power, as well (moderate discharging away from the “knees”, for example).

 

[Samcat]

When you start heavy user watch your voltage drop across all cells....and if some drop more than the rest inspect bus bars and make sure you have no gap under the bus bars ( you can use flash light you should not see any light across the cell terminal and where bus bars meet). Also make sure you have clean surfaces. Inspect also under load drop across wiring from battery terminals before bms to inverter voltage drops. 0.2 V is not good connections. It will work but you will have more losses on the efficiency lost over wiring. Make sure you have adjusted proper values for BMS. Right out of the box they are all over the board for cell V, current limit for charging and etc.