smkettner wrote:
These wires should never melt unless poorly installed.
Everything is protected with a circuit breaker to prevent overload.
This is THE correct answer.
If the wiring was overheating at the converter panel, connections and (splices if any) were not done properly at the factory and/or the tech did not do it right. It is not uncommon to find inadequately tightened terminals in a converter panel. OP should check them all.
If the shore power cord plug blades are pitted and dirty, that can cause heating and a meltdown.
If the CG breaker tripped, and you are near the nominal 120 volt level, it's because you just had too much on. If the AC and water heater were on and not much else and the breaker tripped, the voltage was probably low.
If the voltage is at or near 120V, the AC and water heater should work together fine. Only an AC unit will cause the current to go up, for everything else, it goes down so as the voltage drops, you will get closer to the point where the 30A breaker will trip.
As long as terminations and splices in the main 30 amp circuit are all good, either the CG breaker on the one in your TT should trip. Usually the CG one does because it's a bit on the tired side.
I wonder how OP is making out with this?