Often I am seeing my grid usage is all over the place, ESS seems unable to keep it near zero. Its mostly high levels of export when none is expected. Grid setpoint is 0 but its often exporting more than 500w. This isn't just transient as the AC loads change but consistent over many minutes/hours.
It seems to happen when there is excess solar and either ESS is not able to bring the grid to 0 or the commanded value isn't implemented as charging power. Occasionally I see the system discharging higher values from the battery (2-3kw). Once solar is less than the AC loads it works as expected.
As a test if I increase the grid setpoint to offset the discharge power value then this brings it in check so proves the battery is able to accept the excess power level.
All grid meters are ET112 with USB to RS485 cables connected directly to the Cerbo. The solar W readings match the PV inverter and the AC loads values look correct but has not been tested with a meter.
See below for more specifics but if I can add any info then let me know. Any help debugging this would be appreciated. Thanks!
Canbus BMS Params
ESS Setup
DVCC Setup
System Overview:
Cerbo GX Running Large OS 3.11
2x Multiplus 48/5000 running in parallel single phase. v506 Firmware. (internal current sense).
2x Seplos Mason 48v 280Ah batteries connected via BMS-Can and using DVCC
AC Connected 5kwp solar on AC input.