The Guide to Power Inverters for Homes

Investing in a power inverter is an excellent choice, especially if you want to run your household electronic devices without snags like power interruptions. 

Your household’s power requirements may differ from that of your neighbor’s, so you shouldn’t just blindly get the same inverter installed in your home, too. And that is why this article is here to guide you on the basics of power inverters for home use.

What is a power inverter?

A power inverter is any electronic device that converts low-voltage direct current (DC) power from a battery to standard alternating current (AC) power. It enables you to operate electronics, household appliances, power tools, and other electrical equipment using the power generated by a vehicle battery (a car, truck, boat battery, etc.) or renewable energy source, such as solar panels or wind turbines. 

An inverter draws its power from either a small 12V battery or numerous smaller batteries (wired in parallel). When the power in the inverter is depleted, it will need to be recharged with a car motor, generator, wind turbine, solar panels, or electrical supply.

Power inverters come in various voltage and load capacities, so you should select one according to your requirements. A DC source (battery) is connected to a transformer through the center tap of the primary winding.

inverter used in car adapter

How does a power inverter work?

The DC power from the battery flows in one direction from the negative terminal of the battery, through the completed circuit, and back to the battery’s positive terminal. But typical 12V or 24V batteries provide only low-voltage power. Appliances must run on 120V or 230V AC power, depending on your location.

How are power inverters typically used?

In addition to providing AC power to run your electrical equipment in RVs, cars, trucks, boats, etc., power inverters are used to protect your home electric appliances and belongings during a power outage. They do so by providing emergency backup power to your essential equipment, such as freezers, medical devices, smartphones, sump pumps, microwave ovens, etc. 

There are two types of power inverters (not to be confused with the types mentioned below as they are based on the mechanism of power inverters). The first is a basic power inverter that provides AC power from a vehicle’s battery. The second one is expensive, and it is an inverter charger that is used to provide backup alternating current power in case of an emergency, such as a power outage.

 solar inverter

Types of power inverters

There are three types of power inverters based on output waveforms:

1. Pure sine wave power inverter

AC has a continuously varying voltage that keeps on swinging from positive to negative. This comes in handy while power transmission over a long distance. To get pure sine wave, the power from the grid is carefully regulated. Also, the sine wave radiates the least amount of radio power during transmission over a long distance. However, it is expensive to generate true sine wave in an inverter. At the cost of its expensive process, all the electronic and electrical appliances in your home will work quite well in a sine wave power inverter.

The significant advantage of this type of inverter is that all household appliances are made to operate in sine wave alternating current. Another advantage is that the true sine wave is a type of soft temporal rise voltage that doesn’t produce harmonic oscillations that can result in unwanted counter forces on engines, surge current on condensers, and interference on radio equipment.

2. Modified sine wave or quasi sine wave

Modified sine wave power inverters are used to simulate sine wave, since generating it in the true form is expensive. This modified sine waveform consists of a flat plateau of positive voltage that drops to zero for a short period and then drops to a flat plateau of negative voltage. After this, it goes back to zero again and returns to positive. Quite complicated, right?

In simpler terms, inverters that generate modified sine wave can adequately power household appliances. Additionally, they are more economical compared to their true sine wave counterparts. However, they may encounter certain problems with appliances like laser printers, some music systems, microwave ovens, and digital clocks.

3. Square wave power inverter

Square wave power inverters are the cheapest compared to the types mentioned above. They produce the simplest form of output wave and are used to run simple appliances without any issues. The square wave that these inverters generate can easily be made using a simple oscillator. 

If you want to run essential home appliances and are not looking to invest in an expensive power inverter, then getting a square wave inverter is a great choice.

How to choose a suitable power inverter for your home

1. Understand your power requirement

One of the most important considerations before buying an inverter for your home is your power requirement. To put it simply, you need the power required to run all (or some specific) electrical appliances of your home at the time of power outage, such as fan, tube lights, CFL, television, microwave oven, etc.

For example, you need three fans, 1 CFL, 1 TV, and three tube lights to run simultaneously during the power failure. Below is the power requirement of all these appliances:

  • 1 Fan – 70 Watts (210 watts for three fans)
  • 1 tube light – 60 watts (180 watts for three tube lights)
  • 1 CFL – 25 watts
  • 1 Television – 120 watts

Total power requirement: 210+180+25+120= 535 watts.

2. Find the VA rating of the inverter you need

VA stands for Volt ampere rating. This rating is the current and voltage supplied by the power inverter to the appliance. Most inverters have an efficiency range from about 60 percent to 80 percent, depending on the type of inverter and manufacturer. This efficiency range of a power inverter is also called the power factor. So, most power inverters have a power factor ranging from 0.6 to 0.8.

Hence, VA rating = power requirement / power factor (efficiency).

VA (power of inverter) = 535 watts / 0.7 (power factor)

VA= 765 VA

So, you want a power inverter with a VA rating of 765 or more. According to these requirements, an inverter with 800 VA is available in the market, and it will be the right choice for your house.

What’s the difference between continuous load and peak load?

The continuous load is the wattage that the power inverter always runs at. On the other hand, the peak load is the starting load, which is necessary to get the appliance powered up. Almost all inverters have a peak load double its continuous wattage. For instance, if an XYZ inverter has 500 watts of continuous output, it might have a peak load of 1000 watts (more or less).

Conclusion

A power inverter is an excellent addition to your home to provide instant backup power in case of an emergency. Another best thing about power inverters is that you can carry a lightweight one in your car and use it to convert the car’s battery power to AC power and run your household appliances.