Thanks grsthegreat! This outage was mid-afternoon and only lasted about an hour. We ran errands during the first part of the outage and only cranked the genny when the power was still out upon returning to the house. We never ran the microwave during this outage, but ran it successfully in previous outages. The meters (A & B) on the switch never reached 50% when I switched to genny power, so I don't think it was an overload condition that caused the failure.
I'm wondering if something failed in the generator windings, or other internal parts, and fried the caps in the inverter. While running the genny after the failure, I tried to push the 'Overload Reset' button and it attempted to reset. It sounded like a gang of switches (crickets) trying to engage and the engine reved up, but returned to the idle speed with 100% load LED lit again in about 5 seconds. Really don't know what to try next. B&S factory service is non-existent and local shops will not return my calls. Any help is appreciated.