Hi. I had an installer setup a Growatt 5KW with a Hubble 5.5KW battery. Since installation, I’ve had three blown coils - (2 on the garage door motor and 1 in the sliding gate motor. Both motors are ET. I’ve now had to remove this circuit from the solar backup supply. The Frequency on the inverter is set to 50Hz - which I thought could be causing the problem. Any ideas what is causing this? 

Edited February 2, 20223 yr by Bashir

Maybe test thee neutral and earth  and check the voltage between them.