Inductive Proximity Sensor

About Inductive Proximity Sensor

An inductive proximity sensor  typically contains and works using these main parts:

Short contents / components:

1. Oscillator generates a high-frequency electromagnetic field

2. Coil (inductor) creates the sensing field in front of the sensor

3. Detector / Trigger circuit senses changes in the field

4. Signal processor decides when a metal object is detected

5. Output circuit provides ON/OFF signal (PNP, NPN, NO/NC)

6. Housing protects internal components (metal or plastic)

Short working principle:

• The coil produces an electromagnetic field.

• When a metal object enters the field, eddy currents are induced.

• These currents reduce the oscillator amplitude.

• The detector senses this change and switches the output.

Key point (short):
 Detects only metal objects, no physical contact required.