Solid-state flow switches

A thermal flow switch in use
A thermal flow switch in use

Reliably and accurately monitor liquid flow

Flow sensors are critical to many industrial applications where the continual flow rate of liquid must be ensured, such as in the monitoring of cooling lubricant in machining centers. Our BFF flow sensors include a switching output that is activated when the flow falls below a user-defined rate.

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When a reduction in flow is detected, the sensors can alert the user to a failure of a critical pumping system, a clogged filter, leaks, or other potential system problems.

The completely solid-state calorimetric sensing technology measures temperature differential on each side of the sensing probe and has no moving parts. So, unlike mechanical flow switches, they are resistant to failures caused by dirt or foreign object buildup.



  • Calorimetric sensing principle with no moving parts
  • More reliable than mechanical switches
  • Threaded-in and in-line versions available
  • Visual display of flow with integrated LEDs
  • Flow velocity range: 1...150 cm/sec

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