The input to the PLC indicating a part is present on a typical stepper motor indexing table comes from which component?

The input to the PLC indicating a part is present on a typical stepper motor indexing table comes from which component?

• A. Sensor
• B. Stopper Motor
• C. Conveyor
• D. Actuator

Answer: (B)

Detecting that a part is at the correct position is a sensing task. In a stepper motor indexing table, the PLC needs a reliable signal that a part is actually present before proceeding with the next action. That signal comes from a sensor placed at the index station—such as a photoelectric or proximity sensor—that detects the part’s presence and feeds a digital input to the PLC. The motor itself simply positions the table; it does not provide a presence indication. A stopper motor can move a physical stopper but doesn’t confirm that a part is there. A conveyor might bring parts into the area, but without a sensor at the station, the PLC wouldn’t know when a part is present. An actuator moves components, but again, it doesn’t serve as the presence detector.

Detecting that a part is at the correct position is a sensing task. In a stepper motor indexing table, the PLC needs a reliable signal that a part is actually present before proceeding with the next action. That signal comes from a sensor placed at the index station—such as a photoelectric or proximity sensor—that detects the part’s presence and feeds a digital input to the PLC. The motor itself simply positions the table; it does not provide a presence indication. A stopper motor can move a physical stopper but doesn’t confirm that a part is there. A conveyor might bring parts into the area, but without a sensor at the station, the PLC wouldn’t know when a part is present. An actuator moves components, but again, it doesn’t serve as the presence detector.