18.104.22.168 Requirements for Electrical Means
(a) render the terminal speed-reducing device inoperative
(b) permit the car to restart after a normal stop
(a) be operated by the movement of the car
(b) have metal operating cams
(c) have contacts that are positively opened mechanically
(d) be the enclosed type
(e) be securely mounted in such a manner that horizontal movement of the car shall not affect operation of the device
(a) One or both means to control upward movement of the elevator shall be controlled by the terminal speed-reducing device, either directly or through an intermediate device.
(1) Where an intermediate device is implemented with a solid-state device or software system to satisfy (a), the failure of any single solid-state device or a software system failure in the intermediate device shall not render the terminal speed-reducing device ineffective.
(2) Redundant devices used to satisfy (1) shall be checked prior to each start of the elevator from a landing, when on automatic operation. When a failure as specified occurs, the car shall not be permitted to restart.