Inductive Proximity Sensor
Explore the fundamental principles behind one of industrial automation's most reliable components. This guide interactively demonstrates how inductive sensors detect metallic objects without physical contact, leveraging the power of electromagnetism.
How It Works: An Interactive Simulation
Follow the four-stage process of detection. Use the slider below to move the metallic target closer to the sensor and observe how each stage is affected in real-time.
Stage 1: Field Generation
The sensor's internal LC oscillator circuit generates a stable, high-frequency electromagnetic field at the sensing face. This field is the medium for detection.
Oscillator Amplitude
Detection State
Performance Deep Dive
Understand the key factors that influence a sensor's performance in real-world applications, from sensing distance to target material and physical construction.
The Critical Influence of Target Material
The sensor's detection range is specified for mild steel. Other metals induce eddy currents differently, affecting the range. The chart below shows typical correction factors. Click a bar to see how it affects a sensor with a 10mm nominal range.
Sensing Distance (Sn)
The "range" is defined by several specifications. For reliable design, always use the Assured Operating Distance (Sa).
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Nominal (Sn): The ideal, rated distance.
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Real (Sr): Actual distance, accounting for manufacturing tolerance (±10% of Sn).
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Usable (Su): Accounts for temperature and voltage variation.
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Assured (Sa): The guaranteed "safe" range (0-81% of Sn).
Shielded (Flush) Design
A metal shield contains the magnetic field, projecting it forward. This prevents interference from adjacent metal, allowing the sensor to be mounted flush in a metal fixture.
- ✔ Allows flush mounting in metal.
- ✖ Shorter sensing distance.
Unshielded (Non-Flush) Design
The field emanates from the sides as well as the face, creating a larger detection zone. It cannot be mounted flush in metal but offers a greater sensing distance.
- ✔ Longer sensing distance.
- ✖ Requires clear space around the head.