Yep agree Was not 100% sure that can happen with a generator but after some reading know now it canProbably the brownout damaged it. I'm no expert but have been told that sensitive electronics like computers for example are easily damaged by brownout.
Mrs set it for 7 minutes and it was running fine for 5 minutes 20 sec then beep and a restart run one minute and that was it
I had it on the same plug as one freezer
Think the freezer just happened to kick in and as you say brownout
Lesson for Joe next time micro wave all alone on circuit when using