I have a multiplus 48/5000 it is grid connected and charges a 58 volt lithium battery made from a 24kw nissan leaf battery, I have a Batrium BMS.
I have 2 issues, my first issue is if I ask the system to charge the battery to a high voltage, for example 57 volts, upon reaching this it sometimes then discharges the battery back into the grid, if I catch this and switch the inverter off and on again it acts normally.
My second issue is with the batrium bms, setting the battery percentage charge. for eample if i set say 55v at 80% charge, within a few short weeks it will sink to say 53v is 80%. this causes the battery to charge less and less and I have to keep re setting the volt/percentage.