Difference Between Pure Sine Wave and Modified Sine Wave

What is a Sine Wave?

A sine wave is a type of AC power output where the waveform of electricity outputted from an inverter, which converts DC power to AC power, forms a smooth wave. The sine wave closely resembles waveforms observed in nature, allowing for stable power supply.

Because sine waves reduce output noise, they are ideal for precision instruments and audio equipment that are sensitive to electrical noise. Additionally, household appliances are often designed based on sine waves, and using different waveforms can lead to malfunctions or breakdowns.

What is a Modified Sine Wave?

A modified sine wave is a waveform based on a square wave, designed to approximate a sine wave but lacks the smoothness of a true sine wave, having sharper edges. As a result, it introduces some instability in power supply.

Specifically, the modified sine wave is characterized by "sudden changes in current." This can result in uneven power supply to connected devices, increasing the risk of malfunctions or failures, especially in precision instruments that require stable power.

However, the lower manufacturing cost of modified sine waves allows portable power stations to be produced more cheaply, which is why lower-priced portable power stations often use modified sine wave output.

While modified sine waves can be used with certain electrical devices, their applicability is limited. Simple electrical devices such as incandescent light bulbs or hot plates can usually tolerate power from a modified sine wave.

Which Should You Choose for a Portable Power Station?

In General, Choosing a Sine Wave is Best

A sine wave is the same type of power as you get from a household outlet. Since household appliances are designed based on sine waves, as long as the power output is sufficient, a sine wave portable power station can be used with almost any household appliance without issue.

While sine wave-compatible portable power stations tend to be more expensive, in recent years, sine wave AC output has become standard, even in lower-priced models. As a result, more affordable portable power stations now offer sine wave compatibility.

Given this, there is little benefit in choosing a modified sine wave portable power station today.

Modified Sine Waves Can Be Sufficient Depending on Usage

If your usage mainly involves simple devices like incandescent light bulbs or hot plates, which can function well with a modified sine wave, and you prioritize cost, then a modified sine wave portable power station could work for you.

That said, as mentioned earlier, sine wave portable power stations have become more affordable in recent years, so if the price difference is small, it is recommended to increase your budget slightly and opt for a sine wave portable power station.