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You are talking about the brake for if the cable breaks. I'm talking about the control system that prevents the doors opening while it is moving, opening in between floors, shutting down if there is a problem, etc.... https://en.wikipedia.org/wiki/Elevator#Manual_controls

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Those doors have also safety systems. Formerly, the circuitry to open the door was closed only, when the cabin was in floor level. Opening and closing required constant push of the push button.

(Have some history in elevation control, because we made some standards in the industry.)

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