View Full Version : Wire sizing help

Lee Schierer
05-06-2012, 9:59 PM
I want to install an outlet so we can connect our camper trailer to power when we are home and use it as a guest house and be able to use all the components in the trailer (lights, fridge, water heater and heat pump/ac). The trailer takes a 30 amp 120 volt circuit. From my sub panel to where I plan to install the outlet will be 35 feet (actual wire length), plus the connection cable for the camper which is another 30 feet in length. I plan on getting a single pole 30 amp breaker for the sub panel.

What gauge wire do I need for this circuit?

Bruce King
05-06-2012, 11:39 PM
10 gauge copper (2 wire plus ground, (hot, neutral, ground)) would be typical for that circuit. You should go ahead and install an RV panel that has 50A 240V, 30A 120V and a 20A 120V so any RV can be plugged in. Here is where i got mine: http://www.jamestownadvanced.com/Products/PowerOutlets/tabid/57/Default.aspx

Be careful with that 30A 120V outlet, even electricans have zoned out and wired them to 240V in the panel due to the size of them which causes them to think "240" instead of 120V.

The RV panel should be fed with 6 gauge copper (3 wire plus ground) but that is only good for one RV at a time which would be typical.