Flow Switches

Our Bulletin 839E Flow Switches monitor and display liquid media flow rate from 0.03 to 3 m/sec (0.1 to 9.84 ft/sec). This sensor measures both flow and temperature and is available with two different probe insertion lengths.

Popular Resources/Quicklinks
Condition Sensors Brochure Solid-State Flow Sensors User Manual


  • Rugged, corrosion-resistant 316L stainless steel housing with IP66 enclosure rating
  • Flow rates of liquid media (calorimetric measuring principle) range from 0.03...3 m/sec (0.1...9.84 ft/sec)
  • Four digit 14-segment digital display
  • Dual NO/NC programmable PNP outputs or 4...20 mA analog outputs with single PNP output
  • IP67 enclosure rating to withstand harsh industrial conditions
  • 316L stainless steel probe
  • Selectable units of measurement °C, °F, or %

Flow Switches

Product Selection

  • 3 A authorized only with sanitary adaptor
  • CE Marked for all applicable directives
  • cULus Listed
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To find additional product information including CAD drawing files, 3D models and more use our Product Catalog.


Resource Publication Number Language
Condition Sensors Brochure 836E-BR001
Solid-State Flow Sensors User Manual 839E-UM002
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Allen-Bradley solid-state sensing devices are designed to produce high-quality results in a variety of rugged environments. The flexibility of switch configuration and mounting options make the 839E suitable for a wide range of applications including:

  • Harsh Chemical Wash-Down — 316L stainless steel construction, laser-etched markings and IP66 rating for food, beverage, and other applications requiring equipment wash-down.
  • Water/Wastewater — Monitor cooling water circulation systems of pumps, turbines, compressors and heat exchangers.
  • Pump Protection — Monitor pump functionality and lubrication systems, leak monitoring in process lines. Monitor coolant flow.
  • Beverage — Filter monitoring and flow/no-flow in process lines.
  • Discrete Batch — Monitor process flows.
  • OEM Machine Builders / Large End Users — Programming with ReadWin2000 configuration kit reduces switch setup time.

See how the 839E Solid-state Flow Switches are used in water treatment applications:

Essential Components Case Studies — View our case studies site to discover how customers have applied Allen-Bradley components in their applications.

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