Absolute Rotary Encoders

Absolute rotary encoders translate rotary motion to a unique binary output code parallel to the mechanical movement of a rotating shaft providing accurate positional feedback.

Absolute rotary encoders maintain positional values on the loss of power. The synchronisation of new positional values resumes on power restoration, so unlike incremental encoders, there is no need to reset the encoder or other electrical devices on restart.

The most popular type of encoder is an optical rotary encoder. As an encoder shaft turns a disk with multiple tracks, one graduated track for each binary bit also rotates. An infrared light beam reads the bit track on the encoder disk, generating a binary code relative to the angular position of the shaft.

There are two absolute rotary encoder types:

• Single-turn encoders repeat the binary output code for each revolution, restricting their use to a 360° cycle, used for speed or angular positioning.
• Due to their mechanical design, multi-turn encoders offer a unique binary code over many revolutions and are generally used for measuring applications.

We offer a vast range of absolute encoders from light-duty to extreme heavy-duty with fieldbus interfaces such as Profibus, Interbus, CANopen, CANlayer2, DeviceNet, EtherCAT, PROFINET, SUCOnet, BiSS, SSI and parallel wiring.

Absolute rotary encoders are available with high resolutions, IP and temperature ratings for applications that demand the best encoder technology.