What is the difference between pure wave vs modified wave inverters?

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The main job of an inverter is to convert the (direct current) from the battery bank or solar panels to the (alternating current) needed for most devices that are used in homes. To do that, you have to take the constant DC voltage and change it to a sine wave curve that goes above and below 0 volts.

When the inverters first came out, the most common way to do it was to make the voltage go up and down, creating a block signal. This is called a modified sine wave or “Modified Sine Wave”. The more advanced modified sine waves perform multiple steps, trying to get close to a pure sine wave.

A modified sine wave inverter can be used for simple systems that don’t have any delicate electronic or audio equipment that can pick up the choppy wave and produce a hum. Older tube TVs and brushed motors are generally fine with modified sine wave. Your digital clock is likely to act funky, and battery chargers quite often just won’t work. Some equipment may appear to work fine, but it can run hotter than a pure sine wave and reduce the life of the equipment.

Pay attention if you are considering purchasing a modified square wave inverter to save a few dollars on your system costs. A lot of modern devices will not work as well and some will not work in this waveform:

In general, because the total harmonic distortion is higher in modified square wave inverters, the motors will run hotter (less efficiently, consume up to 30% more power than with pure sine wave inverters) and will probably not last so long.

Also, a modified square wave inverter will often cause a “buzz” in audio devices and sometimes other appliances such as ceiling fans and microwave ovens.

So that you can have an analogy of a pure wave vs a modified wave inverter it is like running a car with square wheels vs a car with round wheels. On the square-wheel drive the journey will be gruesome and, depending on the sensitivity of the car’s occupants, they may not survive the journey. The round wheels would be the pure wave or “Pure Sine Wave”


The pure sine wave is always necessary for a grid connection system. Generally needed for newer LED TVs, CFL bulbs, and inductive loads like brushless motors. Clocks and audio equipment will perform much better with a pure sine wave.


In general, modified sine wave inverters are less expensive than a pure sine wave inverter, so they are still used in simple systems. But as technology advances, the cost of pure sine wave inverters goes down, making them much more affordable and a favorite option.

At Elementz Energy we only use Pure Wave Inverters or “Pure Sine Wave”

¡Únase al futuro!

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