On 2025-04-06 4:09 PM, Jim Adney wrote:
Hmmm, I didn't know this was ever a possibility. Can you give some
examples of DVMs that have this "feature", where there's no blocking
capacitor on the AC input?
I can't recall a specific model number, but I know I've seen it.
Keep in mind that "true RMS" is the square root of the sum of the squares of a series of instantaneous measurements. Mathematically, that is the DC voltage on a pure DC (i.e. constant value) voltage reading.
You'd have to look at the mfr specs to know for sure. If there's a DC blocking capacitor (which you can always add externally, of course), there should be a spec for what amounts to a highpass filter.
Steve Hendrix
