Inductive Linear Position Sensors Solve Application Challenges

Continuous linear position sensors are used in various industrial automation applications. They come in various mechanical form factors and use several different sensing technologies. In typical industrial automation applications, magnetostrictive linear position sensors are probably the most used type. They use a magnet as a follower to track the position of a moving machine part or mechanism. Known for their reliability, durability, and accuracy, magnetostrictive sensors have a proven track record in linear position sensing.

So, what’s the problem?

Although magnetostrictive linear position sensors perform well in most industrial applications, they may not be ideal in certain situations. Applications with strong electromagnetic fields, like welding (both traditional and ultrasonic) or locations near large AC motors, can cause issues. These powerful fields can interfere with the defined magnetic field that the sensor relies on, resulting in signal anomalies or dropouts.

So, what’s the solution?

In these cases, the solution is to use a sensor that does not rely on a magnetic field. This is where inductive technology-based linear position sensors come into play. Unlike magnetostrictive sensors, inductive linear position sensors use oscillating inductive coupling technology instead of magnets. In practice, this means that inductive linear position sensors are extremely immune to interference from external magnetic fields.

Inductive linear position sensing technology basics

Inductive linear position sensors generate an oscillating inductive field that couples with a passive resonator (a coil) attached to the moving part of the machine or mechanism being monitored – like how a magnet is used in magnetostrictive sensors. This inductive energy is then decoupled back into the sensor, allowing it to determine the precise position of the passive resonator and, thus, the machine’s position through its receiving electronics. This coupling/decoupling process occurs more than 10,000 times per second (10 kHz), ensuring rapid and accurate position tracking.

Inductive linear position sensors are not only problem-solvers in demanding applications — they’re a strong choice for any linear positioning or measurement need that requires accurate, dependable, high-speed position feedback. They are the undisputed go-to choice for environments where electromagnetic interference is a concern.