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Inductive Proximity Sensors
For non-contact detection of metallic targets at shorter ranges
For non-contact detection of metallic targets at ranges generally under 50mm (2 inches). Inductive proximity sensors emit an alternating electro-magnetic sensing field. When a metal target enters the sensing field, eddy currents are induced in the target, reducing the signal amplitude and triggering a change of state at the sensor output.
Advantages of inductive proximity sensors include:
Ignores water, oil, dirt, and non-metallic particles
Insensitive to target color or target surface finish