There are a few things to keep in mind when purchasing an auto 12v inverter. There are many options available to consumers and you really need to look closely at what your needs are before making a purchase. It’s easy to buy the wrong inverter and end up being unhappy with it.
First, you need to decide why you are buying a car power inverter. If all you want is a small power inverter to charge your laptop or digital camera batteries, your needs will be much different than if you want to run power tools from a power inverter in your work truck.
Power inverters should be sized according to the type of use that you anticipate putting them too. Most electrical devices have a sticker or metal plate on them somewhere that lists the wattage requirements to run them. For example, I just looked at the back of my small television an it says 25w. If I was buying an inverter solely for the purpose of powering my small TV I would just need to buy one that was at least 25 watts.
Power tools are usually rated in terms of amps instead of watts. You can calculate the wattage if you know the amps and voltage. The formula is Amps = Watts/Volts. The best thing to do when trying to decide how large of an auto power invert to buy is to make a list of all the items that you will be running at once and add up their individual wattage requirements. It’s also a good idea to try and anticipate the electrical device you plan on using that has the highest energy requirement. Then buy and inverter that is larger than you anticipate needing.
It’s not a good idea to run and car power inverter at or near full capacity. If your device requires 190 watts and you have a 200 watt inverter, you would be working the inverter pretty hard. It would be better to buy a 300 watt unit and it won’t have to work as hard.
For this quality of auto power inverter, you are probably best off purchasing online. High end power inverters are specialty items and it’s rare to find a store that will carry them. Sometimes you can find larger inverters in shops that cater to semi trucks. You’ll find a much better selection and be much more likely to find just what you’re looking for if you shop online.
I’ve purchased a few of these low end car power inverters in the past and none of them lasted very long. I used them quite frequently though. They might have lasted longer if I was only using them on the rare occasion here and there.