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RMS Value for non periodic signals

Hello,

 

to calculate the RMS value of periodic signals there is the VI "NI_MAPro.lvlib:Averaged DC-RMS.vi" available. Is there also a vi to calculate the RMS for non periodic signals?

 

Thanks a lot and best regards,

Michael

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Can you provide a file with an example of your file?

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You will find the VI "NI_MAPro.lvlib:Averaged DC-RMS.vi" by right clicking in the block diagramm "Signalverlauf -> Analoger Signalverlauf -> Signalverlaufsmessungen -> Mittelwert und RMS".

2016-04-28_17h15_05.png

But I think my statement above is wrong. Inside the "NI_MAPro.lvlib:Averaged DC-RMS.vi" for RMS values the VI "RMS.vi" is used. The helpfile tells, the following formula:

 

2016-04-28_17h21_21.png

Because it uses sampled data it calculates an approximation of RMS which should work for periodic and non periodic signals. Am I rigth?

 

Best regards,

Michael

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Hi Michael,

 

RMS = root mean square - and that's what is calculated according to the formula in your last post.

 

What's the difference for periodic and non-periodic signals? There is none: you just calculate the RMS of the samples in your array/waveform…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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