6/11/2015 Sensors - Encoders

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Encoders

Encoders Incremental Versus AbsoluteEncoders

Mechanical Installation andAccessories

Applications Accessories

Encoders

To solve positioning problems in automation, lengths and angles need to be measured as accurately as possible. Encoders can

electronically monitor the position of a rotating shaft to measure information such as position, distance, and speed.

Encoders can have various outputs and they can be incremental or absolute.

How an encoder works

The simplified diagram below identifies major encoder components. An encoder consists of a light source, optical disk, and a

light source receiver. As the shaft rotates, the optical disk passes and breaks the light beam. The light receiver and associated

electronic circuitry converts the on/off light states into an electrical signal as shown in the encoder voltage graph below.

Basic Encoder Components

6/11/2015 Sensors - Encoders

http://www.ab.com/en/epub/catalogs/12772/6543185/12041221/12041235/Encoders.html 2/2

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