Actually there is only a definition of RMS, not subject to "trueness" :)
http://en.wikipedia.org/wiki/Root_mean_square AFAIK, the old instruments that gave a true-"true RMS" output measured the heat generated by the signal when applied to a resistor. That way the waveform shape did not affect the measurement, and they were able to measure with the DC component included, something fake-"True RMS" instruments can't do. Many of the existing instruments assume sinusoidal signals and thus are subject to gross errors. Gaston On Mar 5, 6:15 am, Nick <n...@desmith.net> wrote: > On Monday, March 5, 2012 8:46:42 AM UTC, Cobra007 wrote: > > > Yes, you're right Nick, the Fluke is indeed AC coupled. I didn't > > expect that to be honest as it undermines the definition of "true RMS" > > but a simple battery test shows 0V RMS :-). > > Its not a commonly known problem, even among professional EEs. One of my > DMMs, a Tektronix DMM916, has the option to include/exclude any DC > component as required. I've had "forthright" discussions with some over > what theoretically constitutes true-RMS vs. what they expect/want in > actuality. > > Nick -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
