voltage of dimmer output not reading same on two different DVM's
Ron D. wrote:
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let's say the following:
TRMS meters generally have AC and AC+DC modes, but usually your interested in the AC portion.
** Not true.
The reason for needing a true RMS value is to predict heating in a resistance or maybe a fuse .
So you cannot omit the DC component.
AC meters have a frequency response.
** But DC ones do not and so are all the same.
We talk about average, but the average of a typical sine wave is zero.
** Correct.
Standard AC meters show the "average *rectified* value " scaled up by 11% to the RMS for a sine wave.
...... Phil
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