Re: Powerwatch
Reply #2 –
What Pierce said. It's almost certainly the extension cord between the coach and the power source. I'd bet that someone has replaced one end (coach end?) and did not connect the wires to the proper pins in the plug. You can Google "wiring 20 amp extension cord" for more info.
On edit: It's possible that your house wiring is not correct (especially older homes that once had fuse blocks and now have circuit breakers). You can buy a polarity tester at any hardware store for cheap. Check the socket at the house with one and then check the end of the extension cord (plugged into that socket).
Also, when you use an extension cord some people just uncoil enough to reach leaving a coil of extension cord on the ground. Do NOT do this with your coach extension cord (of any persuasion). If you have a heavy power draw in the coach that coil of wire will be the first one to heat up and catch fire. Uncoil it and spread it around on the ground.
If you have a heater or an air conditioner going (and only ONE a/c or heater and remember that the engine heater counts so be sure that's off) then be sure you check that extension cord for heat.
The charger/converter that charges your batteries when you're on shore power can also draw a fair bit of current. I'd be careful of what else is running if yours is on.
Craig