Which device would prevent crash if hoist rope slackens?

• A. Slack-Rope Device
• B. Final Terminal Stopping Device
• C. Capacity Sign
• D. Data Plate

Answer: (A)

When rope tension can change unexpectedly, the system needs a way to detect slack and stop motion before a crash can happen. The Slack-Rope Device is built to monitor the hoist rope tension and trip the drive or apply the brake as soon as slack is detected. That direct response to a rope slack condition stops the escalator or moving walk before the rope loss leads to uncontrolled motion, keeping the car from crashing into limits or other equipment.

The other devices serve different safety roles. A Final Terminal Stopping Device is designed to stop the car at the end of travel to prevent a collision with the terminal, but it doesn’t address slack along the run. Capacity signs and data plates provide information or limits; they don’t trigger safety actions to stop motion.