- #1

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I think I would use arithmetic mean because RMS is just to account for the +/- direction of voltage, but I'm looking for confirmation.

Thanks!

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- Thread starter RMSquest
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- #1

- 1

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I think I would use arithmetic mean because RMS is just to account for the +/- direction of voltage, but I'm looking for confirmation.

Thanks!

- #2

vk6kro

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I think I would use arithmetic mean because RMS is just to account for the +/- direction of voltage, but I'm looking for confirmation.

Thanks!

You should collect the RMS values and take an average of them over a day or whatever time you like.

The RMS process not only allows for the alternating polarity, it also allows for the fact that the heating effect of a waveform depends on the

So, the top of a sinewave has a much greater effect on the heating than the lower parts. More than you would expect from just the voltage. This is the main advantage of using RMS, especially for waveforms that are not sinewaves.

RMS is the DC voltage that gives the same heating effect as the waveform you are measuring.

If you are sure that the waveform is a sinewave, it is possible to measure average voltages allowing for the polarity and then calibrate this to RMS. Cheaper multimeters have been doing this for years.

- #3

sophiecentaur

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You should collect the RMS values and take an average of them over a day or whatever time you like.

The RMS process not only allows for the alternating polarity, it also allows for the fact that the heating effect of a waveform depends on thesquareof the instantaneous voltage.

So, the top of a sinewave has a much greater effect on the heating than the lower parts. More than you would expect from just the voltage. This is the main advantage of using RMS, especially for waveforms that are not sinewaves.

RMS is the DC voltage that gives the same heating effect as the waveform you are measuring.

If you are sure that the waveform is a sinewave, it is possible to measure average voltages allowing for the polarity and then calibrate this to RMS. Cheaper multimeters have been doing this for years.

If you want to get a meaningful result from 'averaging' your RMS values then you really need to know the length of time over which the 'M' in 'RMS' was calculated or assumed. The above answer seems to assume that we are dealing just with normal AC mains, which is just one example of where RMS is used.

As long as you are taking RMS readings at

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