Are there any good ways to measure voltage with dynamic content? What meters is everyone using for RMS voltage measurement these days? I need a new meter and just wondering if there are any gems out there that can do stuff I haven't been able to do before. I think my old fluke was only good up to 400hz or so last time I checked a millennia ago.
accurate voltage measuring
- Thread starter Jeff Kenney
- Start date
How dynamic a voltage reading are you looking for? An oscilloscope certainly has no problems telling you voltage over time...
If you're looking for things like voltage sag with load, power quality meters are available from several vendors, and the Fluke 287 series of DMMs has some basic logging functionality built in. None of these options are cheap, though.
If you're looking for things like voltage sag with load, power quality meters are available from several vendors, and the Fluke 287 series of DMMs has some basic logging functionality built in. None of these options are cheap, though.
on a load (like for example I could measure 1kz sine at speaker terminals)... but 1k sine waves are not very ideal for real world applications nor do I want to send maximum amplifier output on a high powered subwoofer...
Mark DeArman
Junior
I probably should have specified AC output voltage from an amplifier
Most mid to high-end DMMs list the bandwidth over which they can measure RMS voltage accurately. I seem to recall the Fluke 179 being good to 1kHz. The larger and more expensive 289 has a wider bandwidth, and I believe selectable aperture.
The thing to be wary of when measuring music or noise signals is that hand-held "true-RMS" meters have a very constricted dynamic range limit, which is enough to measure steady-state signals like square waves and triangle waves, but completely unsuitable for music or noise. Random noise has a peak to average ratio of ~12 dB, whereas the peak to average ratio of music is often much greater. I haven't been able to find a standalone true-RMS meter with wide dynamic range since HP obsoleted the 3403c. They can still be picked up used and cheap, but when they die, there's no way to get them fixed.
Digital oscilloscopes have peak-peak and RMS readouts, but I don't know how they do with dynamic signals. The picture will still tell the tale of course.
Don’t need the load. Amplifiers are voltage devices. As long as you are within operating limits, the voltage should not be affected by the load or lack there of.
Back in the days of tubs or early solid state, amps didn’t like being driven hard without a load. Not so much any more.