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Bulletin 873C Proximity-Style Ultrasonic Sensors

Proximity-Style Ultrasonic Sensors

Bulletin 873C Proximity-style Ultrasonic Sensors can detect solid and liquid targets from a distance of up to 1 m (3.3 ft). We offer two versions of this sensor: a background suppression unit with analog voltage output or a standard diffuse mode with a digital output.

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  • 3-wire operation
  • 3-conductor connection
  • 18...30V DC
  • Analog or digital (discrete) output
  • Metal, nonmetal solid and liquid sensing capability
  • Short circuit, false pulse, reverse polarity, overload and transient noise protection
  • Adjustable sensing distance (digital/discrete model)
  • Adjustable background suppression (analog model)


  • 873C Proximity-Style Ultrasonic Sensors


  • UL, cUL, and 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.

Related Products


Bulletin 873C Ultrasonic Proximity Style Sensors Installation Instructions873C-IN001
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Typical applications for the Bulletin 873C Ultrasonic Proximity-style Sensors include:

  • Material handling
  • Packaging
  • Food processing
  • Transportation

Customer Success

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