Operation, Operation Devices And Control Equipment

(1) Operation at top and bottom landings shall be of the constant pressure type. (2) Car operating device shall be of the constant pressure push button type with face of button not to project beyond face on button plate, and shall be of the two (2) hand control type. (3) An emergency stop switch shall be provided on or adjacent to the car operating panel. Stop switches shall be of the manually opened or manually closed type with red handles or buttons and conspicuously marked "Stop." Where springs are used their failure shall not prevent opening of the switch. The emergency stop switch when activated shall stop the movement of the car in any direction. (4) A pressure-operated safety switch shall be installed under the lift platform. This safety switch shall cover the entire area of the bottom of the lift and operate if the lift is obstructed in its downward travel by a force exceeding 4 pounds. The under-car safety switch shall be normally closed and momentary operation shall de-energize a normally "ON" control system to stop movement of the lift in downward direction. SEWER LIFT STATION, PERSONNEL ELEVATORS CHAPTER 0800—3—7 (5) The design and installation of the control and operating circuits shall conform to the following: (a) Control systems which depend on the completion or maintenance of an electric circuit shall not be used for: 1. Interruption of the power and application of the machine brake at the terminals. 2. Stopping of the car when the emergency stop switch in the car is opened or any of the electrical protective devices operate. 3. Stopping the machine when safety applies. (b) If springs are used to actuate switches, contractors or relays to break the circuit to stop an elevator at the terminal, they shall be of the compression type. (c) The failure of any single magnetically operated switch, relay or contractor to release, in the intended manner, or the occurrence of a single accidental ground, shall not permit the car to run.