Instrument voltage regulator polarity

[Don C]

The IVR circuit has a noise suppressor choke between the IVR and the gauges that also smooths out the voltage swings. An analog voltmeter is easier to read due to internal dampening.

 

[boxgranch]

Don, thanks, that's sort of what I figured on the digital and analog meters. A really good tech told me once that he liked to have both at all times. The digital is easy to read, but doesn't catch a lot of telltales for troubleshooting.

 

[Don C]

I went out and connected mine up to a power supply and tried both an analog and the best digital meter I had. I ran 12.8 volts into it and with the digital meter the highest voltage that it showed was 11.4 volts., which makes sense, because when the contacts close it should put out close to the same as the input voltage. The average voltage should then be around 5 to 6 volts. The analog didn't perform as well as I thought it would. It looks like the only way to measure the voltage is with an RMS meter or an oscilloscope. I have a box full of miscellaneous electronic parts and I might go back out later, and jerry rig a choke and capacitor in series with a small load and see how much they smooth out the reading.