How to buy a power inverter
A power inverter buying guide
The function of a power inverter is to turn DC current into AC current so that you can use an appliance you would normally use at home, such as a laptop, from a dry cell source, such as your car battery. They differ from generators in that generators burn some kind of fuel to create electricity. Learning how to buy a power inverter that suits your specific needs will allow you to power your devices safely and without problems.
While there are many power inverter brands, a careful reading of the specs of any power inverter you are considering should help you narrow down which one will best serve your purposes. A careful comparison will help you understand the basics of power inverters.
>> Consider where and how you will use a power inverter
One of the biggest power inverter advantages is mobility. A good power inverter will allow you to use your devices as seamlessly as if you were plugged directly into a proper AC outlet. Power inverter uses are as varied as the people who purchase them, but they fall into broad categories: in a vehicle, at a work site and at your home or in an RV.
In a vehicle such as a car or an RV, you would use a power inverter to run a piece of equipment that you would normally run from alternating current. In an RV, for example, you could run a microwave by using a power inverter. Power inverters for cars, trucks, or RVs may be found under auto electronics.
At a work site, power inverter uses would include providing power for one or more tools when you are not near a regular AC power source.
In your home, you might use an inverter to power a personal appliance, such as a hair dryer, when there is no available outlet nearby.
For short duration use, a power inverter can be used instead of a generator.
>> Consider the type of inverter
The following power inverter comparison chart shows the wattage of the most common power inverter categories and the safest uses for the most common types of power inverters. Lightweight inverters are the only ones safe to use in cars, because inverters with wattage load over 300 might cause your car's fuses to blow.
RVs / boats
Homes / work sites
|Compact / lightweight ||300 ||Yes ||Yes ||Yes |
|Heavy duty ||600-1750 ||No ||Yes ||Yes |
|Inverter / charger ||3000 ||No ||No ||Yes |
>> Consider the size
There are also two other types of power inverters: grid-tie inverters, which are designed to tie into and feed an electric power system, and solar inverters, which are designed to either feed into a commercial electrical grid or be used by an off the grid electrical network. Solar inverters are used with photovoltaic arrays, such as solar panels. Any of the types of power inverters noted in this paragraph may be available as surge power inverters, that is, power inverters with surge protection. Being able to distinguish between the different types of power inverters is the most important function of learning how to buy a power inverter.
Part of understanding how to buy a power inverter is learning the different sizes inverters come in. The most common are:
- 300 watts: This is the size needed for running household appliances, such as desktop computers, VCRs, laptop computers, other mobile office equipment and TVs that are 27" or smaller. These appliances usually connect by a 12-volt plug, such as a car cigarette lighter adapter. You can often find these power inverters in automotive supplies departments or stores.
- 600 watts: This size will run things like 5-amp power tools, TVs larger than 27" and bread machines. These generally connect directly to a 12-volt battery. They also have several grounded outlets, so that multiple appliances can be used simultaneously.
- 1750 watts: Inverters with 1750 watts are used for power tools larger than 5 amps, hair dryers, toasters and microwave ovens. They connect directly to the battery network.
- 3000 watts: This size is useful if you need to run all your household appliances and office equipment off of one inverter. Since these inverters provide power for a continuous load you may need special wiring and/or battery banks to use them.
Power inverters with wattage above 300 watts can generally be found in electronics supplies departments or electronics supply houses.
>> Consider the duration of use
Another important factor to consider when you are learning how to buy a power inverter is how long you intend to use the inverter each time you employ it. Most power inverters are designed for short term use. The power inverter/chargers, however, are designed to provide continuous usage for a longer period of time and for a greater number of appliances or tools.
>> Consider the voltage
Another factor to consider when learning how to buy a power inverter is the input and output voltage. As you look at input voltage, check to see that it matches the voltage of the battery supplying the power. For example, if you are using a 24-volt battery, then you will need to choose a 24-volt DC inverter. When looking at output voltage and you live in the USA, Canada or South America, most AC power is 120 volts. Should you live in another part of the world then the output voltage is typically 220-250 volts AC.
>> Consider special features
Power inverters can actually produce four types of sine waves: square, modified sine, pulsed sine and sine. The two most common in commercially available power inverters are the modified sine wave and the sine wave. Most lightweight/compact power inverters are of the modified sine wave variety, which is fine, since they are only used for powering one device at a time, and the user is usually more concerned with powering a personal device such as a laptop or reading light. These power inverters can generally be found in auto accessories departments.
Once you move up to buying either a heavy duty power inverter or an inverter/charger, however, it is advised to invest the extra money to get a sine wave inverter rather than a modified sine wave inverter. Partly, this is because there is no way to upgrade or clean up a modified sine wave signal. Purchasing the best power inverters you can afford will mean that you will be getting the best output and signal for running your devices. Many power inverter brands in the heavy duty and the inverter/charger classes are sine wave inverters. Again, this is easy to determine by reading the specs.
When choosing among the different types of power inverters, you also need to take into account what type of device you are planning to use it with. This is because many devices, such as hair dryers or televisions, use a high initial burst of power when they are first turned on. Learning how to choose a power inverter that will meet your needs ensures that you will be using it in a proper manner.
Another point to consider when learning how to buy a power inverter is the GFCI outlet. GFCI stands for Ground Fault Current Interrupter. Most current models, and all of the best power inverters, are GFCI compliant and this should not be an issue. Still, a quick perusal of the inverter specs should tell you if the one you are considering is in compliance.
Again, taking the time to learn how to buy a power inverter will ensure that the inverter you buy meets your expectations and needs.