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Trim to Size Paddle Type Liquid Flow Switch


FSW-25:Trim to Size Paddle Type Liquid Flow Switch

Paddle Type Liquid Flow Switch Trim to Size

$279.00 FSW-25

1 year warranty
  • Aluminum Alloy IP65 Head
  • Easy to Install
  • Less than 3 psig Pressure Drop
  • 1" PT Connection
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The FSW-25 flow switch utilizes the force of liquid flow to propel its paddle and to detect the incoming flow or movement of the existing liquid in the pipe. In static liquid or no liquid, the spring is in expanded and presses the magnet downward. The reed switch is normally open.

As flow occurs and the paddle is raised at an upward angle of 20 to 30 degrees (or more), the paddle will push the magnet upward to actuate the reed switch which then closes the circuit. The length of the paddle can be adjusted to the diameter of the pipe. 1" trim size can only be used with metal pipes.

The installation is simple. Cut the paddle to desired pipe size. No smaller than 1" pipes for metal pipes. The FSW-25 is not recommended to be used in 1" plastic pipe (1-1/4 is the minimum for plastic pipes). Before installing the unit to a tee pipe, be sure to apply tape seal to the screw then tighten up. The FLOW mark on the screw hexagon must be parallel to the pipe and the ground.

Housing Material: Aluminum Alloy, NEMA 4 (IP65)
Operation Temp.: -30 to 150°C (30 to 300°F)
Paddle Material: SUS304 (Similar to 304 SS)
Operation Pressure: 355 psig
Pressure Drop Allowance: 3 psig
Set Point Tolerance: ±25%
Repeatability Tolerance: ±5%
Contact Capacity: 30 Watts/200 Vdc, SPDT
Max Viscosity: 200 SSU or 43 centistokes

Pipe Line Sizes
1" 1-1/4" 1-1/2" 2" 2-1/2" 3"
Approx Actuation/Deactuation Flow Rates (GPM water)
Act. De-Act Act. De-Act Act. De-Act Act. De-Act Act. De-Act Act. De-Act
1" 5 4 8.5 6.5 12 9 17 15        
1-1/4"     6.5 4.5 9 7 15 12 23 20    
1-1/2"         14 10 23 16 32 25    
2"             18 12 24 17 33 27
2-1/2"                 20 13 27 22
4"                     22 16
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All amounts shown in USD
Note: Units come with complete operators manual.
Ordering Example: (1) FSW-25 Paddle flow switch with head, $279.00