Detecting all areas: Selecting the best sensor

The advantage of inductive proximity sensors is that they offer non-contact detection of both ferrous and non-ferrous metal objects. This means that they are wear resistant and maintenance free, waterproof, widely resistant to chemicals, and are unaffected by moderate levels of dust
and dirt. They also have excellent resistance to shock and vibration and give predictable results. 

This makes these sensors ideal for use in machines where a more traditional switch might prove problematic or impossible to use because of the presence of dirt and moisture.
They are commonly used to detect metallic targets. That is because there are three primary components to an inductive proximity sensor: an inductive coil with an oscillator, evaluation circuit, and an output circuit. When an oscillating signal is applied to the coil, a
magnetic field is created. The presence of metal nearby disrupts this magnetic field. This is detected by the evaluation circuit, which energises an output signal. 

The combination of these properties enables inductive proximity sensors to be used for numerous applications, including gear tooth detection,
speed monitoring, end of travel detection, and positioning/closure detection – in industries such as food and beverage, transportation, agriculture, and packaging.

There are numerous inductive proximity sensors available, so how do you select the best sensor for a particular application?

Read the full article in DPA's October issue