Free online Sensor Technology Course - This short PLC sensor training introduces the three most common industrial sensors.
A little PLC sensor training free.
Learn more, see Instrumentation: Discrete and Sensory training
Various sensors types help us throughout life, often with one not realizing the sensors behind the scene feeding sensor signals to control devices. Above training module is a brief intro to sensor technology. We review three of the most common sensor types found in industrial equipment...
Photoelectric Sensors: Also used on your garage door.
Inductive Proximity Sensors: Also used in elevators. Inductive detects only metallic objects.
Capacitive Proximity Sensors: Also used on your smart phone when you put your ear to the screen during phone call. Detects liquids and other dielectric (ex: porcelain, glass, plastic) materials.
If you prefer, or in addition to going through the material sensor technology material above, you may want to see the Sensor Technology Course video (subscribe while there). It may also be of use to you to know the photoelectric sensor and the inductive proximity sensors are typically less expensive than the capacitive sensor. Then there are sensors even more expensive like the ultrasonic sensor, sonar, the vision sensor, etc.
Most reading this page might be more familiar with the industrial sensor technology applications. With photo sensors being the most popular. Out the two basic photoelectric sensor type, retro-reflective (break the beam) is the most reliable, the other type being the diffused type (light reflects off object being detected). When metal is to be detected like on a machines safety gate, inductive proximity sensor is most reliable. Capacitive sensors are big in the assembly and packaging industry detecting product or bulk material.