Multi-Turn Magnetic Absolute Encoders

Bulletin 842A Multi-Turn Magnetic Encoder is a 25-bit absolute multi-turn shaft encoder. It provides up to 8192 pulses per turn or a maximum of 8192 turns. It uses a technology called Synchronous Serial Interface (SSI) to provide 24-bit resolution over just 5 wires. The SSI output from the 842A encoder can be interfaced in several different ways.

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842A Absolute Encoders Installation Instructions


  • Reduced wiring cost and complexity
  • Noise immunity achieved via differential communication format
  • Simplified start-up
  • Choice of gray code or natural binary formats

Multi-Turn Magnetic Absolute Encoders

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Resource Publication Number Language
842A Absolute Encoders Installation Instructions 842A-IN001
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Typical applications for Bulletin 842A Multi-turn Magnetic Encoders include:

  • Steel mills
  • Overhead cranes
  • Punch press
  • Transfer lines
  • Oil rigs
  • Wind mills
  • Machine tools
  • Packaging

Motion Control Case Studies — View our case studies site to discover how customers have applied Allen-Bradley Motion Control products in their applications.

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