Pure Sine Wave Inverters

A typical Pure Sine wave inverters device or circuit requires a relatively stable DC power source capable of supplying enough current for the intended power demands of the system. The input voltage depends on the design and purpose of the inverter. Examples include:

12 VDC, for smaller consumer and commercial inverters that typically run from a rechargeable 12 V lead acid battery.
24 and 48 VDC, which are common standards for home energy systems.
200 to 400 VDC, when power is from photovoltaic solar panels.
300 to 450 VDC, when power is from electric vehicle battery packs in vehicle-to-grid systems.
Hundreds of thousands of volts, where the invert-er is part of a high voltage direct current power transmission system.

Pure Sine wave inverters which produces a multiple step sinusoidal AC waveform. This is referred to as a sine wave inverter. To more clearly distinguish the inverters with outputs of much less distortion than the “modified sine wave” (three step) inverter designs. The manufacturers often use the phrase pure sine wave inverter. Almost all consumer grade inverters that are sold as a “pure sine wave inverter” do not produce a smooth sine wave output at all, just a less choppy output than the square wave (one step) and modified sine wave (three step) inverters. In this sense, the phrases “Pure sine wave” or “sine wave inverter” are misleading to the consumer. However, this is not critical for most electronics as they deal with the output quite well.

Where Pure Sine wave inverters devices substitute for standard line power, a sine wave output is desirable because many electrical products are engineered to work best with a sine wave AC power source. The standard electric utility power attempts to provide a power source that is a good approximation of a sine wave`.

With more than three steps in the wave output are more complex and have significantly higher cost. The modified sine wave, with only three steps, or one step types of the same power handling. Power supply devices, such as personal computers or DVD players, function on quality modified sine wave power. AC motors directly operated on non-sinusoidal power may produce extra heat. It may have different speed-torque characteristics, or may produce more audible noise than when running on sinusoidal power.