Dwyer Series P1 Brass Piston Flow Switch

Dwyer Series P1 Brass 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 P1 Brass Flow Switches utilizes a piston-type design for accurate detection of excessive or insufficient flow rates. The switches have preset actuation points from 0.10 to 1.5 GPM for liquid flow.


  • Piston-type operation yields accurate detection of low flow rates
  • The piston magnetically actuates a hermetically sealed SPST reed switch


  • Industrial cleaning equipment
  • Detecting loss of fluid in hydraulic systems
  • Assuring proper coolant flow in semiconductor processing


ServiceCompatible liquids.
Wetted MaterialsHousing: brass; Piston: polysulfone; Spring: 316SS; O-Ring: Fluoroelastomer, Other: Epoxy.
Temperature Limits-20 to 225°F (-29 to 107°C).
Pressure Limits1000 psig (68.9 bar).
Accuracy±10% of set point.
Switch TypeSPDT.
Electrical Rating17 A @ 120 VAC, .08 A @ 240 VAC, .13 A @ 120 VDC, .06 A @ 240 VDC.
Electrical Connection18 AWG, 24" (60.96 cm), Polymeric lead wires.
Process Connection1/4" female NPT.
Mounting OrientationAny position. Set points shown are based on vertical, inlet down position.
Required Filtration50 microns or better.
Weight0.66 lb (301 g).
Agency ApprovalCE.

Download Data Sheet: Series P1 Brass Piston Flow Switch

Ref: dwyer-inst.com