RV Electrical Systems

Recreational vehicles operate primarily on 12 volt (battery) power. This battery can be charged by the power converter or the tow vehicles alternator. When the RV is plugged into AC power, the power converter converts it to DC power. The tow vehicle charges the battery through a charge line off the starting battery. The charge line must have an isolator to prevent drawing the starting battery. The fridge, air conditioner and 110 power outlets have direct AC power when the RV is plugged in. Most of the newer units have gas and electric hot water tanks and microwave ovens which get direct power as well. All appliance ignitors, pumps, stereos, fans, interior and exterior lights run on 12 volt power. Trailers that have 12 volt electric brakes, are equipped with a break-away switch that is connected to the tow vehicle. If this switch is pulled, it will lock up the trailer brakes to stop the trailer in the event of a break-away. The brakes are activated by an electronic brake control, located in the tow vehicle. Lastly, the 12 volt system has a fuse box (similar to automobiles) and the 110 system has breakers.