Appreciation post: I swapped the standard brake coil on a 20-year-old Dover for a generic one and it chattered like crazy.

Turns out the old Dover coil had a specific resistance of 42 ohms, and the generic was 38, which the controller didn't like at all. Anyone know a good source for true OEM-spec parts for these older units?

4 comments

4 Comments

patriciarivera2mo ago

Oh man, that's the worst sound. I had the exact same thing happen on an old elevator at my apartment building. We tried a universal coil from a big parts website and it sounded like a bag of rocks in a dryer. The super finally tracked down the right part from a local supplier that specializes in older elevator models. Have you checked with any of those smaller, specialized industrial parts places?

stella222mo ago

Yeah those universal parts are such a gamble. Did your super have to call a bunch of those specialty places, or did they find one that had a catalog for really old models? I've heard some of those suppliers keep records for stuff that's like 50 years out of date, which is wild.

abby_martinez2mo ago

Tbh that bag of rocks sound is exactly why I avoid universal parts for old systems. The local suppliers usually have the right specs to match the original motor. Honestly it's worth calling a few even if their websites look outdated.

felixlane16d ago

Did they check the coil's impedance at operating temp or just cold? Because I've had that bite me back on an old Genie - cold it read fine, but once it warmed up it was way off and caused that same chatter. Those older Dovers are real picky about matching the original controller tune. If the local guys can't help, sometimes the elevator service companies that do retrofits still keep a shelf of those exact spec parts for their old accounts.