Cognex 821-0116-3R, Справочник

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Signal A and B in Quadrature
The distance per cycle is the physical distance that the conveyor system must travel to cause the encoder to output one
full cycle. This distance can be calculated based on the dimensions of your encoder and the length of the image you
want to acquire.
As you configure your Cognex vision software, you determine how encoder cycles affect image acquisition. See the topic
Encoder Resolution and Steps Per Line on page 32 for more information or refer to your Cognex software
documentation.
The DS1000 series sensors support single-channel and dual-channel encoders.
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Single-channel encoders generate only one signal (A). Cognex recommends you use only the PhA+ input of the
I/O cable with a single-channel encoder. Be aware that single-channel encoders cannot determine which
direction the conveyer system is moving, and they are more susceptible to electrical noise than other types of
encoders. See the topic I/O Cable on page 26 for details on the I/O cable.
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Single-ended dual-channel encoders use one wire each for signals A and B. Be aware single-ended encoders
are still susceptible to electrical noise.
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Differential dual-channel encoders use two lines each for signals A and B. Differential encoders greatly reduce
susceptibility to electrical noise.
Single-ended Encoder
Connect PhA+ and PhB+ to the encoder outputs. Derive PhA- and PhB- from the encoder voltage source and make
them equal to 50% of the encoder reference voltage. For example, if the encoder is connected to 24V, set PhA- and
PhB- to 12V.
Differential Encoder
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Image Acquisition