Rotary Encoder

Measuring Rotational Movements

A rotary encoder is a sensor device that converts a position or motion value on a rotating system into an electrical signal. The rotary encoder can be used on rotating machine or plant parts without great mechanical effort. It is only connected to the rotating element (the shaft) via a mounting flange, holes or grooves. Rotary encoders are also used as encoder, rotary sensors, shaft encoder, angle encoder, angle (position) encoder, Angle sensors or angle measuring encoders.

In the industrial environment, rotary encoders are  used for measuring rotational angles on machine tools, in handling and automation technology and on measuring and testing equipment. The exact angle measurement is of great relevance in many technical applications for which the most exact and synchronized axis positioning is necessary (e.g. in robotics, in (multi-axis) CNC machines or in printers). The angle readings of the encoder can also be used to calculate the speed, velocity or linear motion associated with a rotating motion.

A rotary encoder frequently used in industry is the potentiometer, where voltage or resistance changes depending on the angle of rotation. In the case of the potentiometer, a voltage divider is implemented via a sliding contact. Due to wear and lower reliability, especially in harsh environments, however, non-contact technologies (e.g. optical or magnetic rotary encoders) are now increasingly used, which are characterized by high reliability and a long service life.