With our new Victron system, 3x MP2, 3x 15 kWh LiFePo + JK-BMS and Cerbo GX,
VM-3P75CT HQ2423DYNPJ energy measurement, I am exploring various possibilities of Mode 1, 2 and external control (mode 3).
Our house also has 47 panels 400Wp with enphase inverters installed.
Mode 3 is controlled via our Loxone domotics system and is working quite well. No problem here. If charge or discharge mode is requested the system nicely imports or export constantly.
A few anomalies though here in mode 3:
- The max charge current is not determined by the DVCC setting, but by the Max current setting of the first JK-BMS. This looks to me as a software error. Can probable be solved in a next Cerbo- release
- The power setpoints (MB addr 37, 40,41) has to be repeated every 10 second. The documentation reports 60 seconds. It took some time to figure this.
Mode 1 DESS Green mode I was testing next (Tibber provider).
Charging is fluctuating between 0 and 100 A.
- When charging the battery from AC, the power fluctuates strongly. I am puzzled how to avoid this.
- Initially I thought that the Modbus power setpoint, set at 0, that is sent every 10 sec from Loxone spoils the charging process. But after disconnecting the modbus messages from Loxone, the charging remained strongly fluctuating.
How can this be solved?