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High-Frequency Incremental Optical Encoders

Bulletin 844D High-Frequency Hollow-Shaft Incremental Optical Encoders

Bulletin 844D Blind-Shaft and Through-Shaft incremental encoders mount directly to the monitored shaft by a split collar clamp on the encoder, eliminating the need for mounting plates and flexible couplings. You install through-shaft models by inserting the monitored shaft completely through the encoder, while blind-shaft models only require insertion of the end of the shaft.


  • High frequency response
  • Blind-shaft and through-shaft front coupled models
  • Flexible coupler not required
  • Adaptor plate not required
  • 120…16,384 PPR
  • 3.5 in. diameter housing
  • Supports 1/2…1 1/8 in. shafts
  • Cable, connector or terminal block connection options


  • 844D High-Frequency Incremental Optical Encoders


  • CE Marked for all applicable directives

Certifications apply when product is marked. See our Product Certification site for Declarations of Conformity, certificates and other certification details.

Frequently Viewed Publications

Bulletin 844D Incremental Encoder Installation Instructions844D-IN001
More Encoder publications in Literature LibraryAll Languages

Product Catalog

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See our Product Certification site for Declarations of Conformity, certificates and other certification details.

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We offer a variety of accessories for your High-Frequency Incremental Optical Encoders, including:

  • Differential encoder buffer boards
  • Mating connectors
  • Pre-wired cables

View all accessories in the Encoders Catalog [PDF]