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How to upgrade a Modified Sine UPS to Pure Sine? Answered

Hello,

How could I upgrade an uninterruptible Power supply that has a Modified Sine Wave to Pure Sine wave?

I got a cheap 400 watt HP UPS (for a tenner) with a modified sine wave;  then got to discover it would be much nicer that is was a Pure sine Wave ^^. The purpose is to use it as an inverter for most household items (in a solar set-up).

There are videos to increase wattage but I have not found yet something informative enough to upgrade to pure sine.
Thank you!

Discussions

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iceng

Best Answer 3 years ago

Pass the output through a line to line transformer=XFMR or a step-down xfmr wired to an identical xfmr wired step-up.

This xfmr procedure diminishes the third harmonic such that you get a good sinewave.

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steveastrouk

3 years ago

Put the pseudo-sine through a Pi filter, and take off some of the harmonics.

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Downunder35m

3 years ago

You won't find anything as it would mean replacing most of the electronics inside.
And what exactly is nicer about it?

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RincewindTDownunder35m

Answer 3 years ago

ok, thanks. didnt think it would so clear cut.

There is a fair amount of points of views that say that modified is not suitable for long term use on household electronics, can cause the electronics to be noisy and not as efficient than a pure sine counterpart.