How to Wire an RV Campsiteby John Cagney Nash
A recreational vehicle, or RV, campsite must be wired to supply the 20-amp needs of the most modest truck or pop-up camper, the 30-amp needs of a C-Class motorhome and the 50-amp needs of the largest converted motor coach. The most convenient way to establish these supplies is to wire a campsite hook-up box, called a supply pedestal. These are weatherproof, self-contained upright boxes fitted with 20-, 30- and 50-amp outlets all subscribing to the American National Standards Institute designations for plug/outlet shape and size. They are manufactured with integral circuit breakers, and can be purchased with a pedestal light and a usage meter.
Switch off the main breaker box which supplies the RV campsite by throwing the 100- or 200-amp master switch to “Off." Take out the dead-front panel, then test across the power conductor and neutral bus with a voltage meter to ensure the box is disconnected. Confirm that two big hot wires, one neutral and one ground, feed the power conductor, the neutral bus and the ground block in that order. This configuration is called split single phase, and can supply a 50-amp campsite.
Install a 50-amp double-bus circuit breaker in a vacant receiver. Using Type UF–rated, 4-conductor 6-gauge wire, connect the two 120-volt hot wires--typically color-coded black and red--to the 50-amp breaker’s terminals. It is unimportant which color mates to which terminal. Connect the neutral wire to the neutral bus, and connect the green wire to the ground bar.
Site the campsite pedestal where it is protected from accidental contact and the elements. Run the wire from the breaker box to the pedestal, securing it where it cannot be damaged, using cable clips or plastic zip ties.
Follow the pedestal manufacturer’s instructions to remove its case front and install supply. There is usually a grommet-protected knock-out toward the base of the pedestal through which the wire is inserted, and a connection panel nearby with four terminals. Screw the interchangeable red and black hot wires to their marked terminals, the neutral wire to the white-painted terminal and the ground to the green-painted terminal.
Reinstall the pedestal case front and the breaker box dead-front panel, then throw the master switch to “On” to reinstate supply. Using a voltage meter calibrated to 240-volts, test that power is supplied to each pedestal outlet.
- The big wires feeding the circuit breaker box carry unfused current even when the master switch is thrown to “Off.” Touching the unfused circuit shorts metal tools and could be lethal.
Items you will need
- Electrical toolkit
- Voltage meter
- 50-amp fuse (optional)
- Type UF–rated, 4-conductor 6-gauge wire
- RV pedestal
- Cable clips
- Plastic zip ties (optional)
- motorcoach,motorhome,rv image by Greg Pickens from Fotolia.com