There are many differences between pure (true) and modified sine wave inverters. Knowing which to choose will depend on what will be plugged into the inverter. When using sensitive electronics or medical devices it is recommended to use pure sine wave inverters. Because the harmonic distortion is higher in modified sine wave inverters they tend to be less efficient and may cause a buzzing noise from some audio devices and appliances.
Pure sine wave inverters provide an even steady stream of power that often resembles a wave. The power provided is almost identical to household AC power that is cleaner and will run electronics and appliances more smoothly. Pure sine wave inverters also provide power that allows the items plugged into it to run faster, quieter and cooler. Items plugged into a pure sine inverter will have a longer life than if they were plugged into a modified sine wave inverter.
Modified sine wave inverters are generally better with products that run on batteries. The power from modified inverters tends to be choppy and not consistent and often “square” waves. For this reason, they will do better in industrial situations. Modified sine wave inverters are generally more cost effective than pure sine wave inverters.