The current value of the inverter is an unintended value (PW3390)

QUsed instrument: Power Analyzer PW3390 When I measured a newly installed inverter device, the current value came out lower than before. Why is this?

A

In general, the current waveforms of the primary and secondary sides of an inverter are greatly distorted.
When measuring these kind of current, the measurement value will differ depending on the method used to convert the AC to RMS value in the measuring instrument.
The Power Analyzer PW3390 has a switching control of RMS (true RMS value) and MEAN (mean value rectification), which makes it an ideal instrument for measuring inverter devices.

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