EN 81-77-2018 pdf download.Safety rules for the construction and installations of lifts – Particular applications for passenger and goods passenger lifts – Part 77: Lifts subject to seismic conditions.
5.6 Suspension and compensation
5.6.1 Protection for traction sheaves, pulleys and sprockets
The devices for preventing the ropes from leaving the grooves of traction sheaves and pulleys shall include one retainer within 15° of the points where the ropes enter and leave the pulleys and at least one intermediate retainer every 900 of the angle of wrap. The strength and stiffness of the retainers and their distance to the traction sheaves and pulleys compared to the diameter of the ropes shall be such that they are effective.
The devices for preventing the chains from leaving the sprockets shall include one retainer within 15° of the points where the chains enter and leave the sprockets.
5.6.2 CompensatIon means
Compensation means provided according to EN 81-20:2014, 5.5.6 shall be guided in the pit in order to limit them from swaying and reaching snag points.
5.7 Precaution against environmental damage
Hydraulic lifts shall be provided with a rupture valve. The rupture valve shall comply with the requirements of EN 81-20:2014, 5.6.3.
5.8 Guide rail system
5.8.1 General
The guide rails, their joints and attachments shall comply with the requirements of EN 81-20:2014. 5.7 and they shall also withstand the loads and forces generated by the design acceleration (ad).
Where retaining devices are provided, car and counterweight or balancing weight retaining devices shall be used as frame supporting points in the guide rail verification.
NOTE Annex D describes an example method for selecting guide rails.
5.8.2 Permissible stresses and deflections during seismic event
5.8.2.1 Where retaining devices are not provided, the maximum permissible defiections of the car guide rail system shall comply with the requirements of EN 81-20:2014, 5.7, taking into account the load and the forces generated by the lift system including the forces generated by the design acceleration (ad).
5.8.2.2 Where retaining devices are provided, the requirements stated below shall be fulfilled. The safety factors for guide rails shall satisfy Table 3.
All machinery, pulleys and associated overhead beams and supports, rope attachments, overspeed governor, tension pulleys and compensation rope tension devices shall be designed and anchored to prevent overturning and displacement as a result of the forces imposed on them including forces generated by the design acceleration (ad).
Hydraulic lifts shall preferably use flexible pipe work but where the use of rigid pipe is essential it shall use flexible pipe at the end of each rigid length.
5.10 Electric installations and appliances
5.10.1 Electric installations in the lift well
The fixing of landing switch devices or final limit switches, vanes or similar devices fixed in the well shall be designed and installed to withstand the loads and forces imposed on them including forces generated by the design acceleration (ad). In addition, the devices mentioned above shall be protected against damage caused by ropes and cables swaying in the well.
5.10.2 Behaviour of the lift in case of failure of the mains power supply
For lifts in Seismic lift category 2 and 3, in order to avoid people to be trapped in the car in case of failure of the normal power supply, the lift has to be able to move automatically the car to the next landing in up or down direction.
At landing the lift shall operate as described below:
a) a lift with automatic power operated doors, when parked at a landing, shall open the doors, remove the lift from normal operation and keep the door open;
b) for a lift with manually operated doors, when the car arrives at the designated landing. its door(s) shall be unlocked and the lift removed from normal operation.
Where EN 81-73 applies or local regulations do not permit the doors to remain open, a means shall be provided to open the doors (even with the electrical power on) enabling the rescue service to check whether the car is present and persons are not trapped (see EN 81-20:2014. 0.4.2).
The automatic dispatch to the lowest landing as defined in EN 81-20:2014,5.12.1.10 a) shall be rendered inoperative.
The behaviour of the lift in case of failure of the normal power supply shall not override any of the following:
— the electric safety devices;
— the inspection operation (EN 81-20:2014, 5.1 2.1.5);EN 81-77-2018 pdf download.