There are typically 3 or 4 things that trip a breaker
OVER CURRENT.. Well that's what is supposed to trip them
Vibration (I mean VIBRATION!!!!!!!) generally this only applies to a generator at shutdown or perhaps washboard alley.
Some do not like very high temperature environments. (Do not think that was the cause we are talking close to boiling here). (May be caused by bad connection)
And last.. this will cause FREQUENT tripping, not once every year or so.
Defective breaker. I had that happen to me a few times at campgrounds with the campground main 120 volt breakers.
