Inductive Sensor – Working & Its Applications

The inductive sensor is used to detect a metal object. It works on the principle of electromagnetic induction which inducts the magnetic field when current flow through it.
Near the changing metallic field if there is an object then current flow in the object.

The new magnetic field is generated and this new magnetic field opposes the original magnetic field.
The inductive sensor also detects the nonferrous metal target, but it decreases the sensing range.
Its sensing range is the distance from the sensor face to the distance of the sensor to detect a metal target and the sensing distance is 12mm.

It works only if the object is steel and it has a significant amount of iron in it.

Working of Inductive Sensor

It detects metal objects located in their measurement field.
The interaction of the metal object as an electrical conductor with the emitted magnetic field of the sensor.
In the electrical conductor, eddy currents are induced, which extract energy from the field and thus affect the level of the oscillation amplitude.

The core of the inductive sensor is a coil, which allows the magnetic field to flow in a specific direction.
The oscillator located back to the sensor uses an LC resonant circuit to generate a magnetic field, which flows from the sensing face of the sensor.
Then eddy currents are induced in the metal object located in the measurement field.
The oscillator changes the signal level. The change in signal level then switches the output stage in binary sensors via a Schmitt trigger.
In measuring sensors, this change in signal level affects the analog output signal depending on the object distance.

It can be used to detect parts in place at workstations, conveyor stops, and robots.
It is used to detect if an air cylinder is extended or retracted and if a pallet stop or chain transfer is raised or lowered.
It is also used in traffic signals to control the intersection of the road.
Inductive sensors can be used to tell the VFD (Variable frequency drive )when to slow down and stop.
It is also used in Space magnetometers to investigate electromagnetic waves in space plasma as well as natural electromagnetic wave observations on Earth.