Pure sine wave or modified sine wave inverters?

There are generally two types of inverters on the market for residential use. These are pure sine wave and modified sine wave inverters. The differences between the two are quite substantial in overall usefulness and cost.

They are ‘pure’. This means a cleaner running system that allows most equipment that would run on standard electrical power outlets to be powered by the inverter. This purity of this sine wave allows for a lower harmonic distortion factor similar to the standard power outlet.


With a pure sine wave power inverter sensitive electronics will run better overall with more efficient processes and less audible noise. There are some types of electronics that will not work at all with a modified sine wave and this much more expensive version is the only true answer to your power needs.

Modified sine wave power inverters are generally much cheaper in cost than the pure sine wave inverters. However, the price drop comes with a cost in efficiency and noise reduction. They will reliably run equipment that isn’t as sensitive as some high-end electronics but they may generate an electrical hum or distort sounds in some manner.


There are a few types of electronics that a modified sine wave power inverter cannot run effectively. Generally any highly technical piece of electronic computer should be checked with the manufacturer to determine if a modified sine wave will work for you. Laptops, laser printers, optical hard drives, and a great deal of medical equipment such as oxygen concentrators will not work properly with this type of power inverter.