Can I Use a Cigarette Lighter Inverter?

When and where should you sue a cigarette lighter inverter?

Close-Up Of Automatic Cigarette Ignition Lighter

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While there’s nothing wrong with plugging an inverter into your cigarette lighter socket, or any 12V accessory socket, there are some limitations on what you’ll be able to power with that type of connection.

If the electronics you want to plug in draw less amperage than the cigarette lighter fuse is rated for, then the inverter should work fine. That’s typically about 10 to 15A. If you need more amperage than that, then you'll need a different wiring solution.

The Problem With Plug and Play Cigarette Lighter Inverters

While cigarette lighter inverters are convenient, they all suffer from the same design limitations. Unlike inverters that are wired directly to a car battery (or to a dedicated circuit), a cigarette lighter inverter draws power from the cigarette lighter circuit. That means you can’t put a load on this type of inverter that draws more current than the cigarette lighter fuse can handle, or else you’ll blow the fuse.

Additionally, cigarette lighter circuits may have more on them than a lighter socket. These circuits often have additional 12V accessory sockets tied into them, and they sometimes also provide power to dash lights, the head unit, and other electrical components. If the cigarette lighter circuit in your vehicle has any of these additional loads, that further diminishes the amount of current you can draw from an inverter that’s plugged into it.

Bigger Isn't Better (When It Comes to Fuses)

Before you swap out your 10A cigarette lighter fuse with a bigger one, consider the following: Every fuse in that fuse block is sized appropriately for the corresponding circuit, and those fuses serve a vital function. They are designed to sacrifice themselves to save the rest of the circuit. In some cases, this may prevent a fire.

If you simply replace your cigarette lighter fuse with a bigger one, you may be fine. But since the circuit in question was only designed to handle 10A (or whatever the fuse is rated for), you may also be creating unnecessary risks.

Say, for example, some of the wirings in the circuit are only designed to handle a little over 10A. If you plug enough stuff into your cigarette lighter inverter to pull 20A, then those wires are going to be the primary point of failure instead of the fuse. In a best-case scenario, you’re then looking at some inconvenient, costly rewiring. If you aren’t that lucky, you might end up with an electrical fire.

What Can You Plug Into a Cigarette Lighter Inverter?

First find out the size of your cigarette lighter fuse, as well as how much amperage your equipment draws. If a device draws less amperage than the cigarette lighter circuit is rated for, then the inverter should suffice.

Remember there is a difference between the amperage that an AC device draws and the amperage that the inverter draws in order to convert the ~12V DC from your car’s electrical system into 110V AC. As a rule of thumb, a cigarette lighter inverter shouldn’t draw more than 100-120W. Some dual-use car power inverters are wired with this in mind. If that’s the case, the inverter will be limited to around 100W when plugged into the cigarette lighter and, thus, able to handle its full continuous rating when hooked into the battery.

Some devices you may be able to plug into a cigarette lighter inverter include:

  • Laptops.
  • DVD players.
  • Handheld video game chargers.
  • Mobile devices.
  • Phone or battery chargers.

These devices fall into the general range of amperage usage that a cigarette lighter inverter uses. But if you want to use a cigarette lighter inverter, you should check the amperage rating of the device to make sure the inverter can handle it.

Of course, anything that you can safely plug into a cigarette lighter inverter you can also be powered directly from a 12V accessory socket with the correct adapter, which is much more efficient.