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Installed a new controller in a 1960s Otis and it threw a fit
Was retrofitting an old Otis in a downtown Denver building last month and the new microprocessor board kept erroring out on the third floor. Has anyone else run into ghost voltage issues when mixing new guts with old wiring?
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gibson.nathan5mo ago
Oh man, ghost voltage is a nightmare. Had the same thing on a 1970s Dover.
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ross.jessica5mo ago
I read somewhere that ghost voltage is basically just capacitive coupling from nearby live wires, not actual current flowing through the circuit. It's wild how much it freaks out a multimeter though, I've seen readings over 50 volts on a completely dead wire. Someone on a different forum said you just need a low-impedance multimeter or a simple load like a resistor to bleed it off and get the real reading. Makes sense why old houses with shared neutrals or ungrounded systems seem to have it worse, especially with all that cloth wiring still in place. I swear half the "hot" wires I find in my own place are just phantom readings from that stuff.
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