Which signal indicates the system has reached its full travel and triggers de-energization of the motor?

Which signal indicates the system has reached its full travel and triggers de-energization of the motor?

• A. End-of-travel indicators
• B. Position sensors
• C. Electrical interlocks
• D. Limit switches

Answer: (D)

Reaching the end of travel is detected by a limit switch, a device actuated by the moving part when it hits the preset stop. The limit switch delivers a clear electrical signal to the control system, which then de-energizes the motor or stops the drive to prevent over-travel. End-of-travel indicators just show that travel is complete, without automatically stopping the motion. Position sensors monitor position but aren’t inherently a shutdown signal, and electrical interlocks are about preventing operation for safety rather than signaling that travel is finished.

Reaching the end of travel is detected by a limit switch, a device actuated by the moving part when it hits the preset stop. The limit switch delivers a clear electrical signal to the control system, which then de-energizes the motor or stops the drive to prevent over-travel. End-of-travel indicators just show that travel is complete, without automatically stopping the motion. Position sensors monitor position but aren’t inherently a shutdown signal, and electrical interlocks are about preventing operation for safety rather than signaling that travel is finished.