Papa Bob 1* 2008 Brookside by Sunnybrook 32' 1* 2002 F250 Super Duty 7.3L PSD Husky 16K hitch, Tekonsha P3, Firestone Ride Rite Air Springs, Trailair Equa-Flex, Champion C46540 "A bad day camping is better than a good day at work!"
What type of circuit are you trying to plug the rig into? Is it a 50 amp service, a 30 amp service, a standard 20 amp household plug or a ground fault 20 amp plug? What is a amperage rating of the breaker that is tripping? Very likely you have some items that are "on" in the RV that are overloading the circuit if it is a standard 20 amp household plug. The amperage from a battery charger, a converter, the refrigerator and the hot water heater can add up real quickly if they are set to electric.
Try isolating the issue by turning off all the circuit breakers in your power distribution center and turn them on one by one independently. Common culprits seem to be shore power cord cap, failed converter, or a shorted element in the hot water heater.
I had this happen to me with my last RV. I finally found that it was the plug on the trailer. It had a bad connection that was causing a high resistance problem and drawing too much current. The plug was one of those that you could take apart. I opened it up, cleaned up the connections, retightened and never had a problem again after that.
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