Incremental Rotary Encoders

Incremental rotary encoders translate rotary motion to electrical output signals; these output signals are input to other electrical devices to determine position, direction or speed.

The most popular type of encoder is an optical rotary encoder. As an encoder shaft turns, a disk with graduated line gaps connected to the shaft and internal to the encoder housing also rotates. An infrared light beam passes through the graduated line gaps on the encoder disk; electrical signals are output as the light beam is interrupted.

Incremental rotary encoders come with a minimum of two square wave electrical output signals: channel A and channel B, phase-shifted by 90 electrical degrees.

When programmed to accept encoder inputs, phase-shifting allows coupled electrical equipment to add in one direction and subtract in the opposite direction, used for bi-directional counting applications. It is possible to use output signals A and B independently for applications that require counting and frequency feedback from one encoder.

A marker channel comes as standard with every encoder. The marker channel emits one pulse per revolution, is used as a reference point to assist location and reset other devices, or can be used to count rotations.

We offer a vast range of incremental encoders from light-duty to extreme heavy-duty with excellent protection ratings, suited to applications where extreme temperature, shock and vibration occur.