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nicoddg avatar image
nicoddg asked

Distorted output waveform Phoenix 400W 12V 500VA inverter

Hi, I’m using a Phoenix 400W 12V 500VA pure sine wave inverter in an off-grid system for some household utilities. As a result of operating problems with the home gas boiler I performed measurements on the inverter output voltage and I noticed that the phases, though presenting a voltage between them of 220Vac, show a shift towards earth (measured values of the two phases to earth: 70V ac and 140 V ac against the 126 of the mains voltage). Furthermore, the positive half wave tends to distort under load. Is there anyone who has had the same problem?

Phoenix Inverter
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1 Answer
Alexandra avatar image
Alexandra answered ·

@Nicoddg

On the secondary side of an inverter, the voltage and current’s fundamental wave includes harmonic components Some meters pick up voltage how you are testing in inverter systems as they do not have the filtering for that.

I do get some voltage between the L and N (with the basic meter) to the earth point on the inverter. There is no amperage though. I consider this normal.

I would still check the outgoing circuit. If you removed or unplug the circuit and test the circuit (no inverter connected) separately do you have and continuity to earth? Are there dimmers or similar controllers on the circuit. These also cause voltage readings to earth.

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