When the elevator speed exceeds the set speed of elevator speed limiter or when the suspension rope is broken and slack, Elevator Safety Gear Device will activate emergency stop and clamp the lift car on the guide rail.
Figure- A certain type of safety gear
The safety gear test should be carried out in free fall, and the following data should be measured directly or indirectly:
a) Total height of falling
b) Braking distance
c) Average braking force
d) Maximum and minimum instantaneous braking forces
e) Allowable mass (P+Q)1=brake force/16
When the lift car with rated load is in free fall, the average deceleration of the progressive safety gear during braking should be 0.2gn~1.0gn (gn is the standard acceleration of gravity, and the value is 9.81m/s2).
Finally, the test engineers can select the appropriate data interval for the collected data, then they are able to use the software to automatically grab the data nodes, and perform specific formula calculations. As a result, related test results such as action speed, deceleration, braking distance, braking force can be obtained immediately.