What is the function of the hoist limit switch?

• A. To start the hoist motor.
• B. To reverse the crane rotation automatically.
• C. To adjust load capacity.
• D. To stop the hoist at its designed travel limits to prevent cable over-travel and damage.

Answer: (D)

The hoist limit switch is a safety device that stops the hoist when it reaches its designed travel limits. When the hook reaches either the upper or lower limit, the switch is activated and interrupts power to the hoist motor or sends a stop signal to the control system. This prevents the wire rope from over-traveling beyond what the drum and rope can safely handle, protecting components like the rope, drum, and winch gears from damage and avoiding jams or unsafe operating conditions. It isn’t involved in starting the motor, reversing direction automatically, or adjusting the crane’s load capacity; those functions are managed by other parts of the control system.