The reason I gave up my Vol-Con Elite was because of false-positives on de-energized wires. Same situation as a lot of the ones here: A 277 volt three-way I was trouble-shooting; wires run in pipe. Kept getting strong 120V readings on some of the wires. All the wires are the same color so I'm cussing the original installer thinking I have two different voltages in the same box with the same wire colors. Can't even remember how I finally figured out I was reading induced voltage on de-energized travelers, I just know it took me a long while to do it.
I never really liked the term "phantom voltage" because thinking it isn't really there could turn you into a ghost!
I agree. Went to T/S a light a helper was working on. We're getting approximately 120V on a neutral wire. Being the studious guy, he suggests "phantom voltage", and I was inclined to agree. The neutral was in a conduit about 150' long with about fifteen other conductors. Normally ghost voltage is nothing, but in that case it would've been more than enough to knock someone on their butt. Even with two wiggys on the wire, there wasn't enough of a load to drop the reading below 100V!
-John
