RV Electricity | 12 Volt DC | 120 Volt AC | Battery | Inverter All of the electricity coming into the RV is 120 Volt AC. While some of it is going to the outlets within your RV to power your coffee maker, TV, Computer and perhaps a roof AC unit, the rest of that 120 Volt AC is going to a very special box that “converts” those 120 Volts AC to 12 Volt DC. Common 12-Lead Generator Wiring Diagrams PDF fileCommon 12-Lead Generator Wiring Diagrams Series Wye (416/480V 3ø) Voltage L-L: 416/480V Voltage L-N: 240/277V Voltage CT – N: 120/139V Parallel Wye (208/240V 3ø) Wiring Diagrams for Electrical Receptacle Outlets - Do-it Wiring a 20-Amp 240-Volt Appliance Receptacle. This outlet is commonly used for a heavy load such as a large air conditioner. The outlet should be wired to a dedicated 20-amp/240-volt circuit breaker in the service panel using 12|2 awg cable. With this wiring, both the black and white wires are used to carry 120 volts each and the white wire is wrapped with electrical tape to label it hot.