Which statement best differentiates a proximity sensor from a limit switch?

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Multiple Choice

Which statement best differentiates a proximity sensor from a limit switch?

Non-contact sensing is the key difference. A proximity sensor detects the presence of an object without requiring physical contact, using methods like electromagnetic fields, capacitance, or light to sense when something enters its sensing zone and then output a signal. A limit switch relies on a mechanical actuator that must be physically touched by the moving part to change state. So, the proximity sensor can detect an object near it without touching, while the limit switch is triggered only by contact. For example, an inductive proximity sensor can sense a metal piece as it passes by without touching, whereas a plunger-type limit switch trips only when the metal piece depresses the plunger. The other statements misstate the nature of sensing, signal type, or typical applications.

Non-contact sensing is the key difference. A proximity sensor detects the presence of an object without requiring physical contact, using methods like electromagnetic fields, capacitance, or light to sense when something enters its sensing zone and then output a signal. A limit switch relies on a mechanical actuator that must be physically touched by the moving part to change state. So, the proximity sensor can detect an object near it without touching, while the limit switch is triggered only by contact. For example, an inductive proximity sensor can sense a metal piece as it passes by without touching, whereas a plunger-type limit switch trips only when the metal piece depresses the plunger. The other statements misstate the nature of sensing, signal type, or typical applications.

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