The W.E. Anderson Division of Dwyer Instruments introduces the Series TDFS thermal dispersion flow switches.
Dwyer Instruments is the preferred source for a complete range of practical and affordable instrumentation.
Series TDFS thermal dispersion flow switches are a range of thermal flow switches designed to indicate whether the flow rate is above or below a user-set flow rate with NO and NC NPN outputs.
The set point can be easily field set by simply tapping the included magnet on the set point target three times at the desired flow rate.
Two LED status indicators incorporated into the unit on opposite sides provide visual switch indication with green indicating when the flow is above set point and red when the flow is below set point.
Series TDFS thermal dispersion flow switches employ an impulse thermal dispersion measurement technique to measure the flow rate wherein the probe is heated above the process temperature and then allowed to cool down to the process temperature. An empty pipe is not a problem with the TDFS unlike some competitor units that will overheat.
Thermal flow switches are superior to mechanical flow switches, offering better long term reliability and life expectancy.
Key advantages of TDFS thermal flow switches over mechanical flow switches:
- No paddles or vanes that can break off into the flow media
- No jams or material stopping the paddle movement
- No seals on movement assembly to wear or leak
- Better long term reliability and life expectancy












