It is being overloaded for some reason.
I would start checking the connections in your rig.
Check all the connections in the 120 volt power distribution panel. Look for melted insulation.
Find someone with an Amprobe to check amperage of the rig when connected. It is possible that something is going to ground in shore power cord. Maybe screw through it or bad metal clamp.
Add you rig to signature, make and model. This would help identifing known issues with that particular unit from others experience.