Finally got that 1980s Otis controller talking to the new display panel

It was a retrofit job at the old Grandview Hotel downtown, and the new panel just would not sync with the old logic board. I spent almost three full days tracing wires and checking voltages before I found a single bad relay, part number KUP-11A, buried in the back of the machine room. Has anyone else had a modern display fail because of one old relay like that?

3 comments

3 Comments

wyattbennett3mo ago

Check the voltage across the coil first.

nancy_owens3mo ago

Oh, the classic "check the voltage" advice. That's the first step for like 90% of electrical problems, honestly. Might as well tell me to make sure it's plugged in.

jordanc6813d ago

Ha! So @wyattbennett's advice to check voltage across the coil was the right call but man, that's like telling someone to check the tire pressure after their engine blew up.