Let me start by stating my Trace inverters were replaced with magnum inverters about 2 yrs ago.
While in a park in S Florida running the AC's I had an approximate load of 42-45 amps per leg (other items Fridge, lights, etc on too). Park breaker kept going out every 45 minutes or so. While park breaker was being repaired (Common white wire on park poll was loose/burnt) I shifted to generator. After half hour or so, power to coach dropped out but gen was still running. Breaker on gen was NOT tripped, gen was still providing power. Turned the rotary switch in the lower bay from auto to gen position. Power came back, all ok.
Once electrician repaired park pole I switched back to park power and put rotary switch in lower bay to auto. Power went out again in about half hour with 42-45 amp loads on each line. Breakers were NOT popped. Switched rotary switch in lower bay to Shore and power came back, systems ran at the higher amperage load without any issue.
I know Featherlight ran all AC power through the original Trace inverters. When the new Magnum inverters were installed I believe it was wired the same. I turn OFF the inverter portion of the magnum inverter at the the control panel so if park power would go off I wouldn't be pulling on the battery's. I assumed (and we all know what that means) by turning off the inverter portion of the Magnum's at the control panel I was bypassing the inverters.
What I think happened (Looking for input from folks who know more about electrical systems) is the AC power was still going thru the Magnum's even though I had turned the inverter portion off at the remote. Because I had so much amperage passing thru the Magnum's I think they over heated, although there were no alarms on the Magnum's. Since I have turned the rotary switch in the lower bay to shore (bypassing the Magnum's) I have had no power loss even while pulling a constant 38-42 amp's per leg on the shore.
NOTE: The generator and inverters are in the 3rd bay and I can see the wires coming from the generator to the 3 position rotary switch (gen - auto - shore). From the rotary switch the wires go to the inverters and to the power panel in the coach. I do not see any transfer switch, I think the Magnums do that when in the Auto position.

Any and all thoughts are welcome
Chuck