Just posting this in case it helps someone in the future
At 10.20 pm last night the House RCD tripped for our Solar installation
It happens when changeover occurs - ie when the inverter switches after AC power is restored
I started troubleshooting:
AC 1 trips the house RCD which is a type B 30ms
AC 1 charges batteries normally, no trip when inverter is charging
AC 2 out (crtical loads) provides AC power normally while charging
Reduced inverter power to 50W in ESS, Turn on AC 1 isolator - trips
Turned PV isolator off, Turn on AC 1 isolator - trips
Unplugged AC 2 out, Turn on AC 1 isolator- no trip
I now have to find which device on AC 2 Out is the cause - pumps, UV, filters etc for a pond
