which kinds of electrical equipment need a pure sine wave inverter to work correctly?
Some people claim that certain loads &quot;may&quot; not work as well, or &quot;may&quot; be damaged, with anything other than a pure sine wave.
Since the power coming out of my wall sockets is significantly different from a pure sinewave, I suspect these sincere and well-meaning people are merely repeating propaganda from the manufacturer of a pure sinewave inverter,
much like people repeat urban legends.
There is only one kind of device that I know doesn't work as well with a non-sine-wave inverter: devices that use a &quot;capacitive power supply&quot;
-- see
How efficient is a capacitive power supply?
for details.
Since a &quot;capacitive power supply&quot; has a power factor near 0, it is questionable whether any &quot;capacitive power supply&quot; meets EU-mandated power factor laws, such as EN61000-3-2.
I suspect that all products -- as long as they were designed after EU-mandated power factor laws went into effect -- should work just as well on &quot;modified sine wave&quot; as with &quot;pure sine wave&quot; inverters.
Of course, I can't possibly know about every product ever designed -- if there is any specific product (that was designed after those EU-mandated power factor laws went into effect) that can't work or doesn't work as well with &quot;modified sine wave&quot; power, I would be interested. If anyone can explain why it doesn't work, in enough detail that I can try to avoid that kind of failure, I would be fascinated and grateful.