Specifications

Types of Inverter
There are 2 types of inverters available for use in consumer applications. These are:
Pure Sine Wave Inverters:
The name pure sine wave inverters come from the wave form of its output. They have pure sine
wave form output as show in above diagram. This is identical or to replicate as close as possible to
general mains. As most electronic products are designed to be powered by mains, pure sine wave
inverters are suitable for all applications, especially motorised devices where it is proven that pure
sine wave power will lengthen the product’s lifetime and run much quieter.
Pure sine wave inverters are more expensive than modified sine wave inverters because they involve
a much more sophisticated design in order to simulate the smooth output of standard mains power.
Modified Sine Wave Inverters
Again modified sine wave inverters are named after their output waveform. The output of the
modified sine wave inverter cycles through positive, ground and negative voltage as shown in the
diagram above, to give a similar output waveform to pure sine wave.
Modified sine wave inverters are a much cheaper alternative to pure sine wave inverters as they
don’t require the complicated system needed to smooth and render the output waveform. The only
down side with a modified sine wave is that it introduces harmonic distortion to inductive and audio
equipment. This is caused by the harsh clipping in the on and off phase changing in voltage.
However, modified sine wave inverters are suitable for heat element devices (kettle, heater, etc) and
devices that have an external or built-in adaptor (laptop, TV, etc).
How do I choose between Modified Sine Wave or Pure Sine Wave Inverters?
Advantages of pure sine wave inverters over modified sine wave inverters:
a) Output voltage wave form is pure sine wave with very low harmonic distortion and clean
power like utility-supplied electricity.
b) Inductive loads like microwave ovens and AC motors run faster, quieter,
cooler and more efficient.
c) Reduces audible and electrical noise in fans, fluorescent lights, audio amplifiers, TV, games
consoles, fax machines, and answering machines.