Hi, i habe a MP System, a 7,5kWh Battery wirh BMS connected over CAN. A raspberry Pi is doing the Cerbo part.
The MP is charging from PV - then discharging when needed. It stops at 20% (that is my low limit configured in the GX). It holds the 20% over the whole night as suddenly it starts discharging to 0%.
This happend sometimes the last days at different times. Is there a parameter that i didn’t recognise?
Regards
Wanni
Are you on grid when this is happening?
Or off grid and the inverter is not switching off at the correct SOC?
What is giving the system the soc? And is the voltage the same each time?
Are you sure your batteries are not switching off because of cell imbalances?
Hi Alexandra, i‘m on grid (Germany)
The SOC is provided by the BMS from a chinese LiFePo4, wall mount, 7,5kWh from Taico. BMS is Victron and Pylontech compatible (you can choose from around 10 different protocols)
I think i came closer to the failure: the battery didn’t charge fully for the last month (only some sunny hours) and that fore the SoC was at 20% but the voltage was down to 46V. And suddenly the SOC dropped (is my opinion)
Yesterday it charged to 100% absolutely full, and over night the SoC of 20% still was at 51V. So i think it needed the optimization with one full charge.
My problem is thatnonce the Soc is at 0% the battery switches to CCL of 0A. Then i habe to disable the Canbus, switch to „keep charged“ an wait for the SoC / Voltage to reach a certain level. After that the automatic is stepping in again.
Thomas
