Inverter sensing GFCI issue

[nothermark]

Ummm, An unbonded neutral will get inductively coupled eddy currents thus potentially tripping the GFI. Basically it is the same mechanism that gives you a meter reading when the probes are in a field but not making contact. The problem in both cases is that without a connection the variable range is too wide to accurately predict what will happen at any time.

[TQ60]

You likely have a ground to neutral bond someplace or a fault.

Step one is to turn every breaker off and test.

If okay then turn on one at a time until trip then troubleshoot that circuit.

If it trips with all breakers off look inside load center and verify all white wires on one buss bar and all bare and green on a different buss bar and there is no connection between them.