A safety device mounted on the counterweight frame that engages the guide rails to stop the counterweight if the suspension ropes fail or the counterweight overspeeds upward.
Full Definition
Counterweight safety gear is required by EN 81-20 and ASME A17.1 in situations where the space below the counterweight travel path is accessible to persons. If the suspension ropes fail and the counterweight falls freely, or if the counterweight moves upward at excessive speed (which can cause the car to descend dangerously), the safety gear clamps onto the counterweight guide rails to stop the motion. The device is triggered by the governor — the same speed-sensing governor that protects the car — through a separate governor rope or by the car safety gear activation. Counterweight safety gear uses the same wedge or roller cam mechanism as car safety gear. Its installation adds cost but is mandatory where occupied spaces exist below the counterweight pit.
