How to Install A Power Inverter

Connecting a small-load power inverter

For current loads of 150 watts or less, you can connect your power inverter by using a cigarette lighter adapter. This is a good way to go if you are only going to use the inverter occasionally and won't be using large equipment.

Connecting a heavy-load power inverter

For powering loads of over 150 watts, you should connect the inverter directly to your car battery. This requires a 4-gauge power cable and draws power directly from the positive battery terminal. An in-line fuse or circuit breaker (typically 80 amp) installed near the battery is a must. Without one, an accidental short circuit could pose a fire hazard and damage your inverter, not to mention your car itself.

Power rings will simplify the connection of the cables to the power source. Unscrew the nut that secures the positive (+) battery terminal to the battery post, slip the power lead terminal over the bolt that secures the battery terminal to the battery post and replace the nut. Do not attach the power lead terminal directly to the battery post.

How and where to ground your inverter

The ground wire should be the same gauge as the power cable and must make direct contact with bare metal of the car or the negative battery terminal.

Look for an existing bolt or screw that makes contact with the car body near the inverter. Remove the bolt or screw, and scrape away any paint or grime. A star washer will help your ground wire maintain solid contact with the car body. Crimp or solder a ring terminal onto the end of the ground wire, slip it underneath the washer, and replace the bolt or screw.

If you can't find a convenient ground screw or bolt, drill a hole for one. Be careful not to drill into the gas tank or a gas or brake line.