• Used in 1/2" Lines and Larger
  • General Purpose Enclosure
  • Operates in Liquids, Gases and Slurries
  • 316L Stainless Steel Sensor
  • Low Cost, Designed for Industrial OEM and End Users
  • No Moving Parts
  • Can Detect Increase or Decrease of Flow

The FM series is designed to provide an extremely reliable flow switch at a very cost effective price. This series replaces the standard explosion proof enclosure utilized in our FX series with a general purpose enclosure.


The thermal dispersion principle of operation measures a temperature differential between a heated and a reference temperature sensor. The differential varies as flow across the sensor changes. This allows the flow switch to detect the increase or decrease of flow of virtually all liquids, gases and slurries.


The electronics feature a SPDT relay switch output with options for power input of 120 VAC, 12VDC, and 24 VDC or VAC. Field calibration is easily performed by adjusting a potentiometer on the circuit board.

For more information please download a brochure, call us at 1-800-910-6689, or use our part number configurator to Request a Quotation.

  • Low Flow Shut Down of Pumps
  • Flow Indication/Verification
  • Pump or Valve Seal Leakage
  • Bearing Lubrication Flow Sensor
  • HVAC Flow Monitor
  • Safety Shower Flow Switch