Sensor School
Every sensor wired to your PLC is here. Click any card for a free explanation, 30-second animation, and a hands-on Pro exercise.
Beginner Sensors
(4)Start here — the four sensor types you meet on every shop floor.
Industrial Sensors — A First Look
Meet the three sensor families — discrete, analog, and safety — and learn which one your application needs.
Photoelectric Sensor (Photoeye)
Detects parts as they pass — outputs a discrete bit when something blocks the light beam.
Inductive Proximity Sensor
Detects metallic targets without contact by sensing changes in an electromagnetic field.
Mechanical Limit Switch
A mechanical contact switch that changes state when a moving part physically depresses its actuator.
Intermediate Sensors
(6)Add discrete and analog devices used in everyday machine builds.
Float Switch (Level Switch)
A buoyancy-driven switch that opens or closes when liquid level rises to or falls from a set point.
Photo-Fork Sensor (Slot Sensor)
A U-shaped optical sensor with emitter and receiver built into opposite tines — detects objects passing through the gap.
Pressure Transmitter (4-20 mA)
Converts process pressure to a 4-20 mA current loop signal proportional to the engineering-unit range.
Thermocouple (Type K)
Two dissimilar metal wires joined at a measurement junction produce a millivolt signal proportional to temperature.
Ultrasonic Distance Sensor
Measures distance by timing an ultrasonic pulse echo — output is proportional to the target distance.
Incremental Encoder (Quadrature)
Converts shaft rotation into a pulse train — two channels (A and B) in quadrature give position and direction.
Advanced Sensors
(5)Smart sensors, safety devices, and specialised analog inputs for production environments.
Strain Gauge / Load Cell
Measures mechanical force or weight by detecting tiny resistance changes in metal foil bonded to a structural element.
Safety Light Curtain
An optical safety device forming a grid of infrared beams — breaking any beam immediately stops hazardous machine motion.
E-Stop Circuit (Cat 3 / Cat 4)
A dual-channel monitored emergency stop circuit that safely removes power from hazardous motion and detects single-point failures.
IO-Link Smart Sensors
IO-Link turns an ordinary point-to-point sensor cable into a bidirectional digital channel — unlocking remote parameterisation, rich diagnostics, and event data alongside the normal process value.
Intrinsic Safety in Hazardous Areas
Intrinsically safe sensors limit the electrical energy in a hazardous area circuit so that no ignition-capable spark or hot surface can form — even under fault conditions. Zener barriers and galvanic isolators enforce the energy limits between the safe zone and the explosive atmosphere.