Going into the technical details of the topic might take us a couple of pages to get through but I think most people just want to know why Pure Sine inverter seems more expensive and if they need to buy one. We’ll try to answer the question here.
All Power Inverters work by converting Alternating Current (AC, from Utility or Generator) into Direct Current (DC). The majority of the electronics in your house need Alternating Current (AC) to work; this is what the Power company supplies; so your inverter needs to be able to convert the DC store in the batteries to some form of AC. Pure AC has the shape of Waves(or arches) which is why it is called a Pure Sine Wave. The cheaper inverters will attempt to mimic this by generating a modified sine wave which looks like a square instead of a wave. Most non-sensitive electronics will work with this will little or no problem but this might cause a problem for sensitive appliances.
When working on a modified wave source, fans might have some buzz and generate a little more heat and you might notice that the different speed settings are very similar. There will probably be no difference on things like TVs, bulbs, and chargers. Also, due to the slightly higher power usage on modified sine wave inverters, pure sine wave inverters are considered more efficient.
Some devices and appliances that require a pure sine inverter are:
- Laser printers
- Variable speed tools
- Cordless tool battery chargers
- Some TV’s
- Key Machines
- CPAP machines with humidifiers
- Medical equipment
- Sensitive electronics
The major reason why people by Modified Sine Wave inverter is the initial lower cost. If you can afford a pure sine wave inverter, I will say go for it but if you are not using very sensitive equipment or you don’t mind the minor buzz some equipment might give; a modified sine wave might be the way to go.