I was dockside, AC power was on, outlets were being used for tv and A/C and the battery charger (built in) was also working. The AC Circuit breaker/on off switch popped, I shut off all other circuit breaker switches and reset the main AC breaker. I get power to this, but when I turn on any other circuit breaker switch (with the smallest load possible)the main pops again. I can turn on the switch for electrical outlets, it and the main will remain on without a load, however, even the smallest load, I.E. a 5 watt nightlight, is activated then the main, not the outlet breaker/switch will pop again. I have the correct amount of 110 coming onboard through the shore cable. I checked the shore power connections (30 Amp) also the AC panel for any burn marks, odd smells, or loose/corroded wires or connectors. The AC Panel has 5 circuit breaker switches. AC power, Water Heater, Battery Charger, Electrical Outlets, & Microwave. I'm really scratching my head on this one, any ideas for solution will be appreciated and applied.