6.1.5 Driving Machine, Motor, and Brake
(a) Each escalator driving machine shall be provided with an electrically released and mechanically or magnetically applied brake. If the brake is magnetically applied, a ceramic permanent magnet shall be used. There shall be no intentional time delay designed into the application of the brake, except as permitted in 22.214.171.124.4(b).
(b) The brake shall be applied automatically if the electrical power supply is interrupted. The brake shall be capable of stopping the down-running escalator with any load up to the brake rated load [see 126.96.36.199.3(a)(2) or 188.8.131.52.3(b)(2)]. The brake shall hold the stopped escalator with any load up to the brake rated load [see 184.108.40.206.3(a)(1) or 220.127.116.11.3(b)(1)].
(c) Driving-machine brakes shall stop the down-running escalator steps at an average rate not greater than 0.91 m/s2 (3 ft/s2) as measured over the total retardation time. No peak horizontal retardation value exceeding 0.91 m/s2 (3 ft/s2) shall have a time duration greater than 0.125 s (see Nonmandatory Appendix I, Figure I-11). (See also 18.104.22.168.6.)
(d) The escalator brake shall be provided with a data plate that is readily visible and located on the machine brake, and when necessary, a duplicate data plate with the certification mark shall be placed adjacent to the machine brake. The data plate shall indicate
(1) brake torque and related data as follows:
(-a) for fixed-torque brakes, the range of brake torque that complies with 22.214.171.124.1 and 126.96.36.199.6
(2) the method of measuring the torque, designated "BREAKAWAY" or "DYNAMIC," based on the method used when measuring the torque
(4) the type of brake, i.e., fixed or variable torque
(5) the maximum stopping distance with rated load in the down direction that corresponds to the minimum distance between either
(e) Where means other than a continuous shaft, mechanical coupling, or toothed gearing is used to connect the motor to a gear reducer, the escalator driving-machine brake shall be located on the gear reducer or main driveshaft.
(b) multiple and separate chains, each with an individual drive-chain device in accordance with 188.8.131.52.4 and each with connection to the escalator driving-machine brake(s) and/or other brake(s) with capacity capable of stopping and holding a down-running escalator with brake rated load (see 184.108.40.206.3), shall be provided
(b) The escalator driving-machine brake complying with 220.127.116.11.3 and 18.104.22.168.1 shall be applied not later than when the escalator has stopped. Interruption of electrical power to the escalator or driving-machine motor shall automatically cause application of the machine brake.
(c) Activation of electrical protective devices that do not specifically permit dynamic braking shall stop the escalator only by the removal of electrical power from the driving-machine motor and brake.
(d) Stopping performance shall be monitored in conformance with 22.214.171.124 throughout the retardation period at intervals not greater than 25 ms and shall cause the removal of electrical power from the driving-machine motor and brake if the deceleration does not conform to the requirements in 126.96.36.199.1(c) or it is determined that the stopping rate will not result in a stopping distance conforming to the requirements of 188.8.131.52.1(d)(5), where applicable. Nonconformance shall require a manual reset.