Load Indicator (Angle Plate or Load Limiter)
This device is installed near the base of the boom, close to the operator’s position. It moves as the boom angle changes, displaying the angle between the boom and the ground. Based on the boom angle, the operator can refer to the crane’s performance chart and curve to determine key values such as the operating radius, lifting capacity, and lifting height at different angles.
Overhoist Limiter (Also Known as Over-Height Limiter)
Mounted at the pulley block on the boom’s tip, this safety device limits the lifting height of the hook to prevent overhoisting accidents. When the hook reaches its maximum height, the limiter automatically triggers an alarm or cuts off the power source, stopping the hoisting action and preventing overhoisting.
Moment Limiter
The moment limiter cuts off the power to the lifting or boom-adjusting mechanism when the load moment reaches the rated capacity. It also issues a warning signal, preventing overloading and protecting the crane from becoming unstable.
Anti-Boom Back-Tilt Device and Back-Boom Support
These devices prevent the boom from tilting backward when it reaches its maximum allowable boom angle. Once the boom reaches this angle, the anti-back-tilt device ensures it cannot lift further, avoiding accidents caused by the boom tilting too far backward.
