Pure Sine Wave vs Modified Sine Wave

(Credit www.eastwood.com)

All power inverters convert DC power (which is power stored in batteries) to AC power, which is the power supplied by the electric company and fed to your home. Electronic devices need AC power to operate, but power inverters generally output power in two forms, modified sine wave vs. pure sine wave.

Pure sine is a direct replica of the power in your house, and it’s what all 110 Volt electronic devices are made to run on (i.e. anything with a 2 or 3 prong plug).

The more sensitive the device, the less likely it will work well on a Modified Sine. For example induction plates for cooking won’t run on Modified sine.

Newer devices such as camera batteries, air purifiers, computers, tablets, LED TV’s, power tools, etc. may be damaged over time when used on a modified sine wave.

Pure sine is more efficient. The best example is with boiling 1 cup of water in a microwave: on a pure sine it takes 1 minute, on a modified sine it takes 2. Using less energy means you can use more devices, or save money by installing less solar or batteries.

The biggest benefit is not having to replace sensitive gadgets on a semi-regular basis:

• Laptop Battery $140;
• Laptop Charger $80;
• Milk Frother $100;
• AA Rechargeable Batteries $15

Pure sine wave power flows in even, arching waves, whereas modified sine wave power flows to your devices in chunky, square waves. The square waves are giving power to your device “all or nothing,” so to speak. Your device will run properly, or not. The power is coming through in a less seamless fashion. Gaining power that is flowing in modified sine waves does not come through as clean and efficient—it doesn’t flow to the device as “pure.” The devices will get the power they need to operate, but when it comes to devices like fans, TV’s, radios and lights, they will tend to buzz, as they are running a bit “hotter,” due to the way power flows to them.

When considering a pure sine wave inverter vs. a modified sine wave inverter, the thought process can lead you into a side of electricity and power conversion you never cared to see. However, consider the types of devices you’re running and weigh your options accordingly.