I have an induced voltage of 9-14VAC from a 200+ foot cable run of 120VAC. In other words, the 7-wire cable has 120VAC present, which is inducing somewhere between 9 & 14V in one of the wires that comes from an open contact. This is enough to barely turn on a 15V LED pilot light. (I know we should have used twisted-pair or shielded cable.)
I'd like to know if a capacitor to ground could be used to bleed off the induced voltage, when the circuit is open. And what would happen when the circuit is closed, providing 120VAC to the LED light fixture. The manufacturer says the fixture does not contain a dropping resistor, but that the 15V LED bulb doesn't care.
If the capacitor would work, how do we figure the size of the capacitor?