Technical Support

I have 2x12Kw Sunsynk inverters in parallel with 8xGSL parallel batteries. The setup is 50m from the house and have installed an Eastron sdm630 v2 modbus meter as per the Sunsynk instructions. The problem i am seeing is an error W04_meter_comm_fail on a regular basis. The configuration is working and I am getting meter readings but the error appears on a regular basis throughout the day.

I have tried 120ohm resistors, connecting the ground wires etc to no avail - I am using cat 6e shielded cable and the meter shows a steady telephone connected symbol.

The only possible suggestion I can find online is to ensure the modbus id of the meter does not clash with anything else. The meter has ID 1 and changing this just stops the meter talking to the inverter which suggests this is hardcoded into the Sunsynk firmware. The battery BMS is set to 0, the master inverter is 1 and the slave 2.

My though was to change the master and slave ID to 2 and 3 but doing this just stops the parallel set-up and stops the inverters working. No matter how long I leave it and how many times I “reboot”. Changing back to the original Modbus ID’s results in everything working again.

I suppose my question is - is modbus ID 1 significant for the master inverter in a parallel configuration? I could factory reset the inverter just in case something is cached but I am reluctant to do this. Also if anyone has any other suggestions on the meter error it would be much appreciated. It is mention in online forums but nobody has posted a solution yet - it is possible the problem is a Sunsynk firmware issue.