Using extension cordsWhen your power cord just isn't long enough to reach the power receptacle, what do you do? Use an extension cord of course. But there are a few caveats to consider before you plug in that old extension cord laying in the garage. Here are some of those caveats offered by RV Forum staff members.
Use the full length of the power cord that came with your RV and use an extension cord only for the remaining distance to the receptacle. i.e. don't leave your RV's power cord coiled/rolled up and use an extension cord for the full distance from RV to the receptacle.
The gauge (thickness) of the extension cord wire will depend on the distance it needs to reach. Those orange extension cords everybody has are not sufficient; They are usually 16 gauge wire and are limited to 13A maximum at something less than 25 feet. You will want 14 gauge or 12 gauge cord and maybe even 10 gauge if the distance is long. Better still, buy a 30A RV extension cord (available at Walmart or RV stores).
If you're plugging into a receptacle at home, you need a 30A-->15/20A adapter for your RV's power cord or RV extension cord, available at any RV store or at a Walmart if it has an RV section (in the automotive area).
Trying to run air conditioning on 20 amp power will most likely pop the circuit breakers but it would be OK for most everything else.
It's not unusual for RVs to be wired such that they will trip a GFI outlet. The most common problem is the ground and neutral being tied together somewhere in the RV, often in the inverter.
Plugging your 30A power cord into a 50A campground outlet via an adapter will not get you 50A power as the main circuit breaker in your load center is 30A. You cannot use both the 30A and 20A outlets at a campground to get 50A power to your RV; It's 30A at most, again because the circuit breaker in the load center is 30A.
Contributors to this article were RV Forum staffers Gary Brinck, Ned Reiter, Ron Ruward and Tom Jones.