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That week in the Hudson building nearly broke me
Last Tuesday I got a call about a stuck car in a 12-story office tower downtown, figured it was a simple door lock issue. Spent three straight days chasing intermittent faults on a 20-year-old controller, only to find a corroded wire nut hidden behind the selector tape. Has anyone else dealt with phantom faults that vanish the second you open the cabinet?
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mason36125d ago
Corroded wire nut, that's rough. Mildly pedantic point though, those old controllers use a voltage selector tape, not a selector tape. The tape's the thing with the little holes that tells the car where it is, the selector's the whole mechanism. Totally get the phantom fault thing, had one in a 14-story building where the door lock relay would drop out for like 50 milliseconds only when the building's AC kicked on. Three days of staring at a scope before we found the ground wire was sharing a terminal with the HVAC transformer. Drove me nuts, but at least you found the wire nut.
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ivan21125d ago
Did you ever find that the problem only showed up when you had someone else watching? I spent two days on a phantom short in a parking garage elevator, and it finally clicked when I went to grab coffee and left the door open. Soon as the AC kicked on in the stairwell, the thing acted up right in front of me.
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