A power inverter converts your car's direct current (DC) battery power into conventional alternating current (AC) power which can then run a range of household products such as microwaves, power tools, TVs, radios, computers etc when an AC outlet is not available. Particularly useful for camping or long road trips.
Just connect the inverter to your car battery, and plug your AC devices into the inverter and you've got power on the go. (Smaller inverters will connect directly via the car's cigarette lighter)
The Technical Bit...
Two factors determine how a power inverter works: wave output and wattage output. Wave output describes the physical appearance of electrical signals as they move across an oscilloscope. Square waves appear exactly as their name specifies: like squares on a grid. Pure sine waves, also called true sine waves, appear as visible waves on the screen.
How do I know which Inverter to choose?
The first step in selecting a power inverter is to match the inverter to the voltage of the battery you'll be using for power. In the majority of cases, you'll be using a standard 12-volt car battery, so you would want to select a 12-volt inverter.
The next step is to identify which devices you plan to power with the inverter. Each device should carry a label which that tells you the wattage it requires to operate. The wattage rating of your inverter must surpass the wattage of the highest wattage device or the total wattage of all the devices you plan to run simultaneously, or of the largest device.
Some devices draw a higher wattage than their normal operating wattage rating when they first start up. This is known as peak or surge, and this information should also be listed on the device's label. Most power inverters also have a peak rating, so make sure the inverter's peak rating is higher than the peak wattage of the device you intend to power. Microwaves are a special case. As an example, you may know that your microwave is a 400-watt microwave. This is actually the cooking wattage. The power wattage might be twice that amount. Again, check the label on the device to make sure.
Power inverters which run through your car cigarette lighter are designed for lower wattage devices - laptops, phone chargers etc. In fact, if you try to pass more than about 400 watts through a cigarette lighter connection, it will fail -- and it might even start a fire in your vehicle.
