How to Install a Power Inverter in a Car

Ready to install a power inverter in your car but not sure where to start? You've come to the right place!

While small power inverters can be helpful whilst charging small appliances, like a laptop, they are limited by their wattage.

Perhaps, you have a hot plate, microwave, or a hair dryer, in addition to charging your laptop and phone.

At this point, your wattage will be high enough to require hardwiring a power inverter to your car battery, so you don’t end up with a dead battery.

And don't forget, if you need help selecting the right power inverter for your car, check out our detailed guide here.

Step-by-step instructions of connecting the inverter

An inverter under 150 watts can be simply plugged into the cigarette lighter of your car, and you’re good to go. Only you, though, can determine just the right size inverter, so calculate needed wattage for the electrics you plan to hook up.

Choose where to place your inverter

Oftentimes, they are found in the glove box or under a seat, or mounted to the dash. You’ll want the power inverter to be located somewhere dry but not somewhere where it can get overheated.

It also needs to be close to the car battery to avoid losing valuable wattage. If holes need to be drilled in the car, ensure that there are no obstacles on either side and that it is safe to drill.

Additionally, ensure that the wires are away from moving parts or any hot objects. You definitely don’t want your inverter placed on the floor where it could be exposed to water or melting snow.

Lastly, most power inverters come with a fan, so you’ll want to make sure the inverter is located somewhere with good airflow.

Tools

  • Inverter
  • Wire (red and black) 
  • Wire cutters
  • Eyelets
  • Tape measure
  • Cordless drill and accessories
  • Plastic wire ties (to keep the wire in position)
  • Foil tape
  • Circuit Breaker (optional) 

Map out wires

Now that you have a path mapped out for the inverter wires, you need to run two wires (one positive, one negative) through the path. Choosing the right wire for this job is important, because the wrong wire could lead to a loss of power in the car.

Use wire ties to keep the wires in position and if you drilled a hole through the firewall, wrap foil tape around the wires to protect them. If your wires are routed through the car, you will need to seal up the hole with waterproof sealing glue to keep the interior of the car dry.

Mount

Mount the inverter in place. Do not trust glue, but rather ensure the inverter is mounted securely with screws.

Trim

Trim the excess wire and add the eyelets, confirming that they are the correct size for the wire and for their specific terminal.

Circuit Breaker (optional)

If you have purchased a circuit breaker, now is the time to install it. Place it on the positive (+ red) terminal battery, as close as possible to the battery and use sheet metal screws to fasten it.

Eyelets

Install eyelets on your wires if you have not done so already. The eyelets should match the bolts on the battery clamps, so remove the nuts to secure them.

Connect

Connect the positive clamp first, and then the negative clamp. Cross your fingers that it won’t spark or smoke.

Congratulations! You now know how to install a power inverter in a car! You can now charge larger electrical items without worrying about injuring your car battery! 

Emphasis on safety

The advantage of a power inverters is that you can safely charge a multitude of electric devices without risking the battery of your vehicle. It does require careful maintenance though. As with any projects, wiring the power inverter should be done carefully to ensure that the power does not all rush to deliver power to one outlet at one time. That would possibly destroy whatever is plugged into the outlet. Additionally, poor maintenance or installation could also cause the power inverter to be a fire hazard, so make sure that everything is carefully maintained and connected.

Special features to be aware of

Many inverters have a fan in them, and this fan will need to be cleaned occasionally to rid it of dirt. Additionally, if the batteries mounted directly on the inverter leak, they will cause damage, so it is best to use a battery that are sealed to avoid damage. Lastly, an inverter is susceptible to damage from high heat or water, so care must be taken to protect that the inverter remains cool and dry.

Installation of a power inverter in a car is relatively simple, and following both these directions and any further directions that come with your chosen inverter will ensure easy and secure installation for your car power inverter.