ABOUT INDUCTIVE PROXIMITY SENSORS

An inductive proximity sensor is comprised of an LC oscillating circuit, a signal evaluator, and a switching amplifier.

The coil of this oscillating circuit generates a high-frequency electromagnetic alternating field. This field is emitted at the sensing face of the sensor.

If attenuating material nears the sensing face, eddy currents are generated in the case of non-ferrite materials. In case of ferromagnetic materials, hysteresis and eddy current loss also occurs. These losses draw energy from the oscillating current and reduce oscillation. The signal evaluator detects this reduction and converts it into a switching signal.

The terms "attenuated" and "unattenuated" are used to describe the two switching states of the inductive proximity sensors.


LINKS
Inductive Proximity Sensors Product Information (PDF)