Battery disconnect

A battery disconnect is a handy gadget in the electrical system of motorhomes, travel trailers, and fifth-wheel trailers, particularly in the 12-volt setup. It works like a switch, using a device called a solenoid. When you activate this switch, it either opens or closes, turning the 12-volt power on or off in the system. It’s like a master power control for your recreational vehicle’s electrical system.

Most motorhomes have two of these disconnect systems. One is for the house batteries, which power things inside the RV like lights and appliances. The other is for the chassis batteries, which are involved in running the motorhome itself. You can control these switches in a couple of ways. Some need you to manually turn a knob or move a lever. Others are more modern, with an electronic switch that you can operate with a remote control from inside the RV.

When the battery disconnect is turned off, that particular battery circuit becomes ‘dead’. This means no power flows from the batteries. However, big power users like generators and starter motors don’t go through this disconnect system. They’re wired directly because they need a lot of power to operate.