Rodwha
I have a Xantrex freedom inverter, it has two circuits that it inverts power to. Microwave is on the 20 amp circuit and the entertainment system and three other outlets on the 30 amp circuit.
When shore power or generator is supplying power the Xantrex simply passes thru the power. So, if connected to shore power I could just simply flip the breaker off to the Xantrex and it will supply inverted power to those two circuits.
Apologise for some of the nasty posts above! Some, not all of us long time members can get rather crankey. I learned it shortly after joining years ago.
Welcome to the forum!