AN138 : PTE Article, All About Position Sensors – Electromechanical, Electronic and Fiber Optic

AN138

Sensing The Motion, Rotary Position Sensors – Electromechanical, Electronic and Fiber Optic

Published in Power Transmission Engineering magazine, August 2010

Motion control requires feedback. Without feedback, there is no controlled motion. Position sensors are a key
element of a motion control system, regardless of whether the primary power is hydraulic, pneumatic or electrical.
There are a multitude of position feedback sensor options that reflect a very broad range of technologies—from electromechanical
to electronic to optoelectronic to state-of-the-art fiber optics. Design decisions are usually based on a
multitude of factors—including environmental, reliability, redundancy, safety and reliability. These applications can
also reflect a preponderance of conservatism versus state-of-the-art in a spirited clash of the old school versus new
school of engineering.

This paper provides an overview of the more common position sensor options and references actual case studies to
illustrate the diverse solutions available and the reasons behind some of the decisions. Three cases are used to illustrate
the needs of different applications leading to the choice of a particular type of position sensor. The cases reviewed
include a gantry crane, wind turbine and aerial cable car.This application note introduces the 3rd Generation MR340 series Fiber Optic Incremental Encoders and its relationship and replacement of the legacy incremental encoder series MR30X, MR31X, and MR32X.