What are the two main components of a limit switch?

• A. The actuating mechanism and the contacts
• B. The coil and the actuator
• C. The housing and the wiring
• D. The timing relay and the solenoid

Answer: (A)

Limit switches work by converting the motion of a moving part into an electrical signal. The two main components are the actuating mechanism and the electrical contacts. The actuating mechanism (plunger, lever, or roller) is what the moving part presses or moves, and its job is to trigger the switch. The contacts are the conductive parts that open or close the circuit when the actuator moves, determining the electrical state (normally open or normally closed).

Other descriptions, like a coil and actuator, refer to solenoids rather than a basic limit switch, and housing or wiring are support features rather than the defining functional parts. Timing relays and solenoids belong to other devices, not to the essential two components of a limit switch.