Interlock between master and station start controls is typically designed to ensure that the system starts only when:

Interlock between master and station start controls is typically designed to ensure that the system starts only when:

• A. The operator holds the start button for three seconds
• B. The motor overload is cleared
• C. The master enable and all required starts are satisfied
• D. The power switch is in the ON position

Answer: (C)

Interlocks gate the start sequence so the system can begin only when there is an explicit authorization from the overall control and every required starting condition is ready. The master enable acts as the primary permit, and the station start controls are allowed to initiate motion only if that permit is active and all necessary starts or safety conditions are satisfied. This ensures the entire system is in a safe, prepared state before any motion occurs. Other ideas don’t fit the interlock purpose: holding the start button for a set time isn’t about system readiness, it’s just a timing habit. Clearing a motor overload is a fault-handling action, not the gating condition that permits starting. Simply having the power switch ON only confirms power availability, not that the machine is permitted to start or that all safety checks are complete.

Interlocks gate the start sequence so the system can begin only when there is an explicit authorization from the overall control and every required starting condition is ready. The master enable acts as the primary permit, and the station start controls are allowed to initiate motion only if that permit is active and all necessary starts or safety conditions are satisfied. This ensures the entire system is in a safe, prepared state before any motion occurs.

Other ideas don’t fit the interlock purpose: holding the start button for a set time isn’t about system readiness, it’s just a timing habit. Clearing a motor overload is a fault-handling action, not the gating condition that permits starting. Simply having the power switch ON only confirms power availability, not that the machine is permitted to start or that all safety checks are complete.