I have recently installed 3 x Multis in single phase parallel system. Everything works OK but as soon as I switch on the grid the one inverter starts humming a couple of times and the goes into passthrough. Thinking one of the inverters could be faulty I configured inverter 1 and 2 in parallel and it worked. Then configured inverter 2 an 3 together and it worked. It is just if the 3 inverters are configured in parallel and i switch grid on that it won’t work. No error codes or error Leds it just won’t work with grid connected. If the 3 inverters are connected in parallel with grid switch of everything is OK but when we switch grid on the one inverter starts humming a couple of times and then the system goes into passthrough. I would be really grateful if someone can help me to understand where I could be going wrong with this.
Are all your ac in and ac out wires the exact same lenght? And same size (awg/mm)?
Go trough all your settings to see if there is any difference
I used 6mm in and out to each inverter. There could be a 3 or 4cm difference from the ac busbar to the ac in and output MCBs
Thank you Marc i will check up on that