What is elevator safety gear?

Safety gear is a set of jaws mounted on the car sling (and sometimes the counterweight) that clamps onto the guide rails to arrest a falling or overspeeding car. It is triggered mechanically by the governor rope, independent of electrical power or the controller.

What is the difference between instantaneous and progressive safety gear?

Instantaneous gear grips the rail almost immediately and produces very high deceleration, so it is limited to 0.63 m/s (0.8 m/s with buffered suspension). Progressive gear uses spring elements to hold deceleration between 0.2 g and 1.0 g and is required above 1.0 m/s.

What is UCM protection in an elevator?

UCM — unintended car movement — protection detects a car drifting away from the landing with doors open and stops it within the distances set by EN 81-20 §5.6.7. It is implemented with a certified rope brake, brake monitoring on the gearless machine, or double-acting safety gear.

How is safety gear tested?

At commissioning the car is loaded to 125% of rated load and dropped onto the safety gear at the governor trip speed, and the arrest, rail marking and deceleration are recorded. The test is repeated at statutory periodic inspection, typically annually.

Can safety gear be reset after it has been triggered?

A qualified technician resets it by lifting the car clear of the gripped rails, releasing the jaws, resetting the governor and inspecting the rail faces and jaw surfaces for scoring. Damaged wedges, springs or scored rails must be replaced before the lift returns to service.

Elevator Safety Brakes & Safety Gear

Matched pair of progressive elevator safety gear blocks with roller wedges, damping springs and mounting fittings, type-tested to EN 81-50 and supplied in Karachi, Lahore and Islamabad — PRT-08 · Elevator Safety Brakes & Safety Gear

PRT-08

In short

Elevator safety gear is the mechanical device on the car sling that clamps onto the guide rails to stop a falling or overspeeding car, triggered by the overspeed governor. Instantaneous gear is used up to 0.8 m/s; progressive gear, which limits deceleration to 0.2–1.0 g, is required above 1.0 m/s. Separately, the machine brake and a UCM device stop unintended movement.

Engineering overview

Safety gear is the arresting half of the fall-protection chain. Triggered by the governor rope, wedge or roller jaws clamp onto the guide rails and bring the car to a controlled stop. Instantaneous gear grips almost immediately and is limited to 0.63–0.8 m/s because the deceleration is severe; progressive gear uses a spring or elastomeric element to hold the retarding force between 0.2 g and 1.0 g, which is mandatory above 1.0 m/s.

The second layer is braking at the machine. EN 81-20 requires two independent braking circuits, each individually capable of holding and decelerating the car with 125% of rated load; disc or drum brakes carry redundant coils, micro-switches proving release, and a manual release for hand winding.

The third layer is UCM (unintended car movement) protection under EN 81-20 §5.6.7 — the lift must detect and stop a car that moves away from the landing with the doors open. Liftech Global implements this with certified rope brakes, brake-monitoring on gearless machines or double-acting safety gear, and verifies stopping distance on site.

Types & variants

Instantaneous safety gear
Wedge or eccentric roller block, immediate grip, ≤ 0.63 m/s (≤ 0.8 m/s with buffered rope suspension).
Progressive safety gear
Spring-damped wedge assembly, deceleration 0.2–1.0 g, for 1.0–4.0 m/s cars and all high-rise duty.
Bi-directional safety gear
Arrests in both directions to satisfy up-overspeed and UCM requirements in MRL layouts.
Counterweight safety gear
Required where an accessible space exists beneath the shaft.
Machine brake (disc / drum)
Twin independent circuits, redundant coils, release micro-switches and manual release lever.
UCM rope brake
Certified rope-gripping device on the suspension ropes, triggered by door-zone plus movement detection.

Technical specifications

Instantaneous gear speed	≤ 0.63 m/s (0.8 m/s buffered)
Progressive gear speed	1.0 – 4.0 m/s
Deceleration window	0.2 g – 1.0 g (progressive)
Brake holding capacity	125% of rated load, each circuit independently
Brake circuits	2 × redundant with release proving switches
Rail head range	b2 = 9 / 10 / 16 mm machined rails
Type test	EN 81-50 §5.3 certified component with data plate
Site test	Full-load drop test at commissioning, periodic re-test
UCM stopping distance	≤ 1 200 mm car movement per EN 81-20 §5.6.7

Gallery

Pair of EN 81-20 progressive elevator safety gear blocks with roller wedges, damping springs, pivot links and complete mounting fittings supplied by Liftech Global in Pakistan — Progressive safety gear pair (left/right) with springs, links and full fitting kit — EN 81-50 type-tested

Two blue cast-body progressive safety gear units with roller wedge stacks and trip levers ready for car sling installation in Karachi — Cast-body progressive safety gear, roller-wedge type — 1.0–4.0 m/s, deceleration held 0.2 g–1.0 g

Elevator safety chain diagram showing overspeed governor, progressive safety gear, oil buffer, governor rope tension unit and steel suspension rope in a Liftech Global safety package — Complete EN 81-20 safety chain — governor, safety gear, buffer, tension unit and ropes

Elevator governor sheave with orange rope wheel, cast counterweight box marked 18 KG and rail-mounted safety gear frame with trip lever for car sling assembly — Governor sheave, 18 kg tension weight and rail-mounted trip frame — safety-gear actuation set

Where it is used

All traction lifts — car safety gear
Counterweight gear over occupied spaces
MRL modernisation requiring UCM compliance
High-rise and hospital cars with progressive gear
Brake replacement and brake-monitoring retrofits

Frequently asked questions