For two years, my Multiplus2/5000 (GX) 3Ph setup worked fine with external control in ESS mode. In my system, I set the power setpoints with an external script at Modbus registers 37, 40, and 41, and that worked flawlessly.
Last week, I updated the software to the latest version, V3.33. I think everything still worked well after that. However, after I selected the ESS mode 'Keep batteries charged', I encountered an issue. I have no external meter connected to the GX, and I have no loads connected to AC out. The system started to charge the batteries at full power. I switched it back to External Control within a minute.
After switching back to External Control, the system continued charging at full power, which did not correspond to the setpoint. Only after stopping the external script from sending new setpoints to 37, 40, and 41 did the system fall into Passthru mode.
I have now disabled the script and tried setting some setpoints manually, but setting a setpoint for one phase causes that phase to start charging at full power immediately. When I read back the input register, the value is written correctly, but upon writing, the system always reacts with full power charging of that phase, stopping after approximately one minute.
Is someone familiar with this behavior? Did I mess up a register value somewhere? How to fix this?
Thank you in advance for your help.
Bart