I'll check the controller tomorrow, I know it's a UCL but not sure of the number. Otis machine with the flying sheave, pie plate selector up on secondary slab with machine (car calls up here also, what a pain in the ass to run the car), slimline/telephone relays up at top of controller, standard Otis relays and contactors at the bottom, different terminals than the standard C1, C2 etc. etc.. they are MKO-1, MK3-5 etc. One of the big four had this contract for years and didn't do Crap. All the relays, rivots, armatures, selectors.. everything's wore slap out from lack of maintenance.

These cars will re-level on the pie plate if they over or undershoot.

Also-

Is the loop at least in the high k ohms to ground?

I yank all the brushes out of the motor and gen set, and put a megger on the loop. Should be meg ohms, or at least like over 200 k ohms.

Got any brush dust carbon trails, taking the loop to ground?

Sounds like a UCLS -maybe 10-21-30 ?

Carbon everywhere, guess I'll meg it. I forgot to check the controller. The machine says 330DM on the side. Went through and ohmed lots of circuits, those Otis contacts are different than I'm used to, my rubber eraser wasn't working, I forgot an old Otis guy suggested I use krokus cloth - it works well. Replaced a couple rubber band shunts, to short arm leveling switches on the selector and adjusted the brake relaxing voltage from 13v up to 20v like the other car. It never tripped the OL today, be back Monday.

Great..As they say down here..

"Small town boy makes good!". 😁

Both the 22 and 29ct machines are great machines...could be a car/ctw..weight problem..didn,t say what operator you removed hope it wasn,t a 6970a they weigh quite a bit..compared to todays operators...balanced load center of the hatch tach your leveling speed in both directions record your armature current as well..good luck.

Dover changed out the old Otis operators years ago to GAL's. We were trying to push a mod and all the customer would spring for is operators, that's all they were willing to do now. We put in Schindler/ECI QKS15's.

i just had one where once a week it would trip the 2p dashpot overload, this is the overload in the loop, vintage is a 21ucl 1961,checked everything oil, shuts, brake, put a megger on everything i could. what i found was carbon tracing on the big resistors on the top rear of the controller, they are the resistor's in the loop to feed your MG set, hit them with some compressed air and a rag(power off LOTO and test and verify)have not had a call back on that elevator in over a month.