Otis 6940A was Otis's elevator interlock. It was most likely used on all Otis elevators most likely from the 1960s-around 2008. Now, Otis uses a different interlock.
Otis 6940A interlock
Elevator Wiki
Otis 6940A was Otis's elevator interlock. It was most likely used on all Otis elevators most likely from the 1960s-around 2008. Now, Otis uses a different interlock.