A number of years ago, I came up with the expression, "All the world is a voltage divider" I think it started with explaining the voltages to ground on battery strings measured with Fluke 77s Vs Simpson 260s. To gain greater understanding, first grab your meter manual and check the specs for the Mohms and pF that reflect it's input impedance. The cut sheets don't usually show these specs but they should be in the manual's expanded specs. Next, draw a circle with a sine wave in it that represents an AC voltage source. Place an "N" and the ground symbol below the source and write 120 VAC or Vrms beside it. To the right, draw a vertical resistor in parallel with a vertical capacitor. Add a ground symbol below them, the values from the manual, and the "M" in a circle meter symbol pointing across them. These things represent what you know. Next, draw a line up and then to the right of the source to a rectangle, then from the right side of the rectangle, over and down to the RC combo. In the rectangle, write inductive coupling, capacitive coupling, and resistive losses??? These are the values that you don't know, yet measure the effects of on your meter.
Now, I guess you decided to perform the death defying 34 volt to ground touch. Yet, you sought out the tingle without the enlightenment. Had you had a meter probe tip in each hand while touching the wire and ground, you would have gained another useful measurement. Had you then switched to ohms and touched the tips with the same pressure, you would know about the amount of parallel resistance that you added to the RC mix.
In a simple, purely resistive world, we could see that we dropped about 1/4 of the voltage with our meter loading. We would assume that if our meter was 10Mohms, that the other 3/4 of the 120 volts was getting dropped over about 30Mohms of lumped effects. But in the real world of AC circuits and reactive components, the voltages across all of the series components will likely add up to more than the total due to phase shifts involved.
I never really liked the term "phantom voltage" because thinking it isn't really there could turn you into a ghost! So could someone killed by induced voltage, be accused of over reacting???
Joe
