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Series Flow Switch  FS-925 Gems Sensors

Gems Sensors Series Flow Switch

This series of precision-calibrated switches provides reliable and consistent performance; repeatability is within 1%. FS-925 units are factory preset for actuation at specified flow rates.
Stock
-1
Code
FS-925

Gems Sensors Series Flow Switch

 General Purpose

Quick Specs... 

  • Flow Rate Settings: Liquids - 0.1 GPM to 1.5 GPM; Air/Gases - see chart 
  • Port Size: 1/4" NPT 
  • Primary Construction Material: Brass or Stainless Steel 
  • Setting Type: Fixed 

Overview / Design Principle: 

This series of precision-calibrated switches provides reliable and consistent performance; repeatability is within 1%. FS-925 units are factory preset for actuation at specified flow rates.

These switches provide accurate detection of excessive or insufficient flow rates in such applications as: protecting against loss of fluid flow in hydraulic systems, assuring proper coolant flow in semiconductor processing equipment, monitoring high pressure lubrication systems, and ensuring proper air flow in water/waste systems.
 

Applications: 

  • Electronic Equipment: Laser Heads, Welders, Power Supplies, High Speed Spindles, X-Ray Tubes, Semiconductor Equipment 
  • Bearings or Gears: Presses, Rotating Equipment, Conveyors, Machine Tools, Robotics 
  • Processing & Dispensing Equipment: Water Purifications and Filtering, X-Ray Film Processing, Beverage Dispensing, Chemical Additives, Gas Sampling, Distilling

 

Specifications: 

 Wetted Materials 

- Housing: Brass or 316 Stainless Steel
- Piston (In Brass Housing): Polysulfone for water, Brass for oil or air
- Piston (SS Housing): 316 Stainless Steel
- Spring: 316 Stainless Steel
- O-Ring: Viton®
- Other Wetted Parts: Epoxy
 

Pressure Rating 

 - Operating, Maximum 

1000 PSIG (69 bar)  

 - Proof  

2500 PSIG (172 bar) 

 - Burst 

5000 PSIG (345 bar)  

Operating Temperature 

 - With Brass or S.S. Piston 

-20°F to +300°F (-29°C to +148.9°C) 

 - With Polysulfone 

-20°F to +225°F (-29°C to +107.2°C) 

Repeatability 

1% Maximum Deviation 

Set Point Accuracy 

±10% 

Set Point Differential 

15% Maximum  

Switch 

SPDT, 20 VA 

Inlet/Outlet Ports 

1/4" NPT  

Electrical Termination 

No. 18 AWG, 24" L., Polymeric Lead Wires 

Switches are U.L. Approved for Class I, Division 2, Groups A, B, C, D hazardous areas.
They are also available with FM-approved explosion-proof junction box for Class I, Division 1, Group D hazardous loactions. Units must be completely assembled at Gems.
 

 

Flow Settings, Air (Typical) Dependent on operating line pressure. Examples of set point ranges at a given line pressure are shown below. 

Line Pressure

Actuation Point 

FS-925 

 FS-926 

 M" 

 Max. 

 M" 

Max. 

5 PSIG (Minimum)

0.5 SCFM 

10 SCFM

2 SCFH

15 SCFH

100 PSIG

1.5 SCFM 

25 SCFM

7 SCFH

50 SCFH

 IMPORTANT REED SWITCH PROTECTION INFORMATION: Read before installing.

Gas Calibration 
Water flow units should not be used for air/gas applications: Gas flow units have a special dash-pot piston for reliable operation. Gas calibration is dependent upon line pressure, switch orientation, and the specific type of gas. The calibrated flow set point is subject to change with fluctuations in line pressure.

 

 Dimensions:

 DimFS925.gif 
A  1/4" (6.3 mm) 
B  9/32" (7.1 mm) MTG. Holes (2) 
C  2-3/8" (60.3 mm) 
D  1/2" (12.7 mm) 
E  1-1/4" (31.7 mm) 
F  1/4" NPT Both Ports 
G  27/32" (21.4 mm) 
H  4-1/8" (104.7 mm) 
I  3/4" (19.0 mm) 
J  1" (25.4 mm) 
K  1-3/4" (44.4 mm) 

Product Documentation

FS-925 Series
FS-925 Series - Download PDF
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