In the following wiring tutorial, we will demonstrate how to properly wire a NEMA TT-30 receptacle using both standard and GFCI breakers. The included wiring diagrams show the correct breaker size and wire gauge for a 30-amp receptacle, making it suitable for travel trailers, RV hookups, and temporary 120V appliances.. What size wire for 30 amp RV service If you are looking to hook up your trailer to a 30-amp, 120V service in your home, then you will need to use at least a 10-gauge wire (or an 8-gauge wire just to be on the safe side).
Black (HOT), 1 White (NEUTRAL) and 1 Ground Correctly sized wire The 30-amp service for an RV is 120-volt with a 3 prong receptacle and a single 30-amp dedicated breaker.. That's because your 30-amp RV outlet needs one neutral, one hot and one ground wire to be connected properly, as shown in this diagram. In fact, it's wired exactly the same way as your 15- or 20-amp home outlets are, albeit with heavier 10-gauge wire, instead of 14- or 12-gauge wiring.