Reading RMS Voltage on DMM's while in Waveform Mode Hardware: Modular Instruments>>Digital Multimeters (DMM)
Problem: I am using my NI DMM in waveform mode to acquire an analog waveform and display it on my front panel. However, I would still like to show a digital display of the measured RMS voltage, much like a hand-held DMM. I tried wiring in the niDMM Read function to retrieve this value, but ended up getting the following error: Solution: It is true that the AC Volts measurement is not supported in Waveform Mode, and only supported in the IVIDMM mode. (The only valid function types for the Waveform Mode are WAVEFORM VOLTAGE and WAVEFORM CURRENT). The simplest workaround is to take advantage of the LabVIEW signal processing tools. There is a VI that calculates RMS, found on the function palette at Mathematics»Probability & Statistics»RMS.vi. Wire the output of the Fetch Waveform VI to the input of the RMS VI to calculate the RMS value of your waveform. Related Links: Attachments:  - DMMerror.JPG
Report Date: 02/08/2007 Last Updated: 02/25/2007 Document ID: 467G39JQ |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
