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Vent: I used to think the old trick for a sticky door operator was just shop talk
Had a 90s Otis unit in a downtown building last month with a door that kept hesitating on close. The usual cleaning and adjustment did nothing. An old timer I used to work with said to check the 24 volt DC at the motor while it's under load, not just at rest. Sure enough, under load it was dropping to 18. Found a corroded splice in the junction box on the car top. Fixed that and the door smoothed right out. Saved me from replacing a motor I didn't need. Anyone else run into voltage drop issues that looked like a mechanical problem first?
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veraj537d ago
Man, that's a solid find. So you're checking load voltage at the motor itself, not just at the board, right?
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cora8637d ago
Remember my buddy who kept blowing boards on his project. He swore he was checking voltage at the source. Turns out he was only probing the controller output. Had him run leads all the way to the motor terminals under load, and bam, we saw a huge drop. That's exactly what @veraj53 is getting at. The voltage at the board means nothing if the motor isn't getting what it needs. He had a bad connection in a crimp that only showed up when things got hot. You ever run into something sneaky like that?
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