SP1800 Paddle Flow Switch

The SP1800 Flow Switch can detect liquid movement in pipes.




The SP1800 Flow Switch can detect liquid movement in pipes. When the liquid is static or nonexistent the switch is in the open position. As flow occurs and the paddle is thrusted forward causing the switch to actuate (closing the circuit). The length of paddle can be adjusted to the pipe’s diameter.

Stock Unit Model Number:

  • SF1800

Housing material: Aluminum Alloy, IP 65
Operation temp: -30BC~150BC
Wetted material: SUS304
Operation pressure: Max. 355 PSIG
Pressure drop allowance: 3 PSIG
Set point tolerance: K25%
Repeatability tolerance: K5%
Contact capacity: 60W 220Vac/200Vdc, SPDT

Please send us an enquiry should you need a different configuration in the SF1800 series.


  • Standard and explosionproof versions
  • Field customizable paddle length, 1~3″ (25.4~76.2mm)
  • Maximum pressure up to 355psi (25bar) and operating temperature to 302⁰F (150⁰C)
  • 1″ PT threaded process connection
  • SPDT output contact, 60W@220VAC/200VDC rating



  • Detect adequate fluid flow for operation of downstream process
  • Protect machinery requiring coolant flow


  • HVAC chillers
  • Petrochemical
  • Power
  • Food processing
  • Many others