20-10-2017, 12:39 PM
Mike was clear about it being the input to the transformer, not the output from the transformer.
Jeffrey, your Rigol scope will do a pretty good RMS conversion of an arbitrary waveform, providing you've got a sensible display on the screen.
Many DMMs extend to 100kHz or more, with a crest factor of 3 or better. The Fluke 8920A goes to 20MHz and is as true-RMS as it gets.
Back to the original question, I suspect that it's the meter that's the problem. Mike says the reading is half the expected value. Which, in round numbers, should be about 1A. But the meter linked to has a 20A FSD. Moving iron meters tend to be a bit inaccurate at the bottom end of their scale. That's probably all it is...
Jeffrey, your Rigol scope will do a pretty good RMS conversion of an arbitrary waveform, providing you've got a sensible display on the screen.
Many DMMs extend to 100kHz or more, with a crest factor of 3 or better. The Fluke 8920A goes to 20MHz and is as true-RMS as it gets.
Back to the original question, I suspect that it's the meter that's the problem. Mike says the reading is half the expected value. Which, in round numbers, should be about 1A. But the meter linked to has a 20A FSD. Moving iron meters tend to be a bit inaccurate at the bottom end of their scale. That's probably all it is...
