The rope, belt, or chain system that suspends the elevator car frame from the traction machine sheave, transmitting the traction force and supporting the weight of the car, cabin, and rated load.
Full Definition
Elevator cabin suspension systems are classified by suspension ratio: 1:1 (ropes connect directly from machine sheave to car and counterweight), 2:1 (ropes reeved through sheaves on the car and counterweight, halving rope tension but doubling rope travel), and 4:1 (used in high-capacity slow-speed goods lifts). Traditional suspension uses multiple strands of steel wire ropes (EN 12385-5); modern gearless traction systems increasingly use coated steel belts (aramid-core or steel-core, polyurethane jacket) that allow smaller sheave diameters and higher efficiency. Minimum number of ropes/belts is two (EN 81-20 Section 9.2); each must independently support 1.25 times the suspended load. Rope factor of safety ≥12 (wire rope), belt factor of safety ≥16 (coated belt) per EN 81-20. The suspension ratio determines the overspeed governor calibration speed (governor trip speed = rated speed × suspension ratio for 2:1 and above arrangements).
