Question for those who work on these situations professionally... I run sound and lights for band and commonly work in clubs where the only quality power available is an older style 30A to 50A "range" or "dryer" style outlet with 2 hots and a neutral. I have used some "distros" built by others where they split each hot through a 20A breaker to an Edison quad box. The grounds are then simply "tied off" inside the distro box, without any real ground connection. Interestingly, the typical outlet tester shows this combo as valid but I wonder about the safety! Would it be better to bond the Edison outlet grounds to the Neutral line, as I think was done with appliances until the code changed to the newer 4-prong outlets? Or, should I make my own ground connection to available cold water pipe, etc.. ?? None of this optimal, but looking for the safest most logical thing to do for temporary hookups... thanks!
The grounds are then simply "tied off" inside the distro box, without any real ground connection. Interestingly, the typical outlet tester shows this combo as valid but I wonder about the safety!
If the tester is just one of the types with three neons connected across each permutation of the wires, this wouldn't be entirely unexpected. Neons draw only a tiny current, so it's likely the ones tied to the "floating" ground could have a sufficiently low-impedance path to glow via either capacitive coupling or leakage through the various equipment connected to the distro board.
#128401 - 01/27/0709:58 AMRe: Grounding a 3 prong Range/Dryer Outlet?