Seeing MuliPlus-II warnings “Low battery voltage” evn the BMS shows cell voltage fare away from warning or alarm level.
When the warning chage to alarm status the ESS (I think) stops discharging and change to grid supply. This happens when SoC is in a range of 20-30%.
SoC is set to 10% in the ESS.
There is a Lynx Shunt between the battery connetor and the distributor box. However I could not measure any voltage drop across the shunt. I wounder because a shunt is a resistor and the voltage across it is the measured parameter ??
Measure voltage at the inverter terminals, then measure it at the battery terminals - compare?
The shunt drop is for its own measurements.
Make sure you have correctly torqued and crimped all connections.
The other way to do it is to use the DMM on AC and measure voltage from pos to pos or neg to neg (one probe on battery terminal and one on the inverter terminal) and check voltage.
Its important to A. Be careful and B. Do so underload.
A third way is to use ve config and check DC ripple (under load)
SoC 43% Load ~8kW
Battery: 49.5V MP2: 49.0V
Load ~12kW >> Low bat alarm >> switch to grid >> Battery goes to more than 50V
In any case DC cell voltage is more than 3V; no alarm from BMS all time
All connections are perfect!
Measure DC ripple to be done soon. Question: DC ripple is shown in ve config?
Batt-Voltage is min ~49V DC (16cells). Ripple is 400mVpp at the MP2 terminal (load. 8kW).
Measurment was done by a battery powered Oszi.
Attached the ESS battery setting. Does “Optimiert” mean the alarm limits are calculated? In other words … when I put the min SoC to 10% in the settings this has no meaning?
Thank you for the tip.
Same here, with SOC limit set to 10% (and active ~10-15%), I had shutdowns at ~28%.
Setting for 0.005C was at51.5V, while battery was going <50.50V at SOC <20%.