Dwyer Series P3 Polypropylene Piston Flow Switch

Dwyer Series P3 Polypropylene Piston Flow Switch

Flow includes Flow Transmitters, Flow Sensors, Flowmeters, Sight Flow Indicators and Water Meters. Mass Flowmeters, Controllers, Flow Indicators and Controllers are ideal for measurement of flow rates. Flow Switches come as paddle, thermal, piezo, and shuttle/piston. Flow Switch Sensors with an electrical contact output at a specific flow rate have different types of switches, which are paddle, thermal, piezo, and shuttle/piston.

Shuttle or piston flow switches are sensors with an electrical contact output at a specific flow rate. Models are used with oil, air, water and gases. Applications include oil flow control, low flow detection in cooling lines, and high pressure lubrication systems. Rugged construction and excellent chemical compatibility simplify flow/no flow detection. The Series P3 Polypropylene Flow Switches fit almost any piping requirements with compatible liquids. Choose the inlet and outlet port to be 3/8" male NPT or 1/4" male “Quick Disconnect” then select a quick disconnect acetal adapter for straight through flow or with a shut off valve.


  • Piston design incorporates a hermetically sealed SPST magnetic reed switch
  • Easy integration to existing piping with a variety of fitting options
  • Selectable shut off valve will stop line flow when the adapter is removed from the switch
  • Economical design


  • Pure water equipment
  • Filter life monitoring
  • Heat exchangers
  • Cooling applications


ServiceCompatible liquids.
Wetted MaterialsHousing: Polypropylene; Piston: PPS composite; Spring: 316SS; O-ring: Fluorocarbon.
Temperature Limits0 to 212°F (-18 to 100°C).
Pressure Limits125 psig (8.6 bar) @ 70°F (21°C); 50 psig (3.4 bar) @ 212°F (100°C).
Accuracy20% of set point.
Switch TypeSPST, N.O.
Electrical Rating08 A @ 120 VAC.
Electrical Connection24" (60.96 cm) polymeric wire leads, 22 AWG.
Process Connection3/8" male NPT or 1/4" quick disconnect.
Mounting OrientationAny position. Set points shown are based on vertical, inlet down position.
Required Filtration100 microns or better.
Weight5 oz (0.14 kg).
Agency ApprovalCE.

Download Data Sheet: Series P3 Polypropylene Piston Flow Switch

Ref: dwyer-inst.com