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GEMS SENSORS Liquid Flow Switch: Piston, PPS, 9/16 in UNF, 9/16 in Connection Size, UNF - General Purpose Piston Flow Switches
GEMS SENSORSGeneral Purpose Piston Flow Switches

GEMS SENSORS Liquid Flow Switch: Piston, PPS, 9/16 in UNF, 9/16 in Connection Size, UNF

The GEMS SENSORS Liquid Flow Switch: Piston is a general purpose piston flow switch with a fixed set point and a normally closed switch position. It features a 20 V DC contact rating, a PPS body, and 9/16 in UNF…

SKU 3G-OTH-89217

Brand
GEMS SENSORS
Item
Liquid Flow Switch: Piston, PPS, 9/16 in UNF, 9/16 in Connection Size, UNF
Category
General Purpose Piston Flow Switches
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Technical Specifications

GEMS SENSORS
Manufacturer Part Number
FS-4, 122356
Type
PPS, UNF, SPDT, Fixed
UNF
9/16 in
Set Point Type
Fixed
Connection Size
9/16 in
Switch Position
Normally Closed
Contact Rating (DC)
20 V
View Full Spec Sheet

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GEMS SENSORS Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The GEMS SENSORS Liquid Flow Switch: Piston is a general purpose piston flow switch with a fixed set point and a normally closed switch position. It features a 20 V DC contact rating, a PPS body, and 9/16 in UNF connections, with SPDT switching. The manufacturer part number is FS-4, 122356.

Frequently Asked Questions

What is the GEMS SENSORS FS-4 liquid flow switch used for?

The GEMS SENSORS FS-4 liquid flow switch is used to detect flow or no-flow conditions in industrial piping systems. It is commonly applied in water treatment, HVAC, and process control to protect pumps and equipment from dry running or insufficient flow.

What are the specifications of the GEMS SENSORS FS-4 flow switch?

The GEMS SENSORS FS-4 is a general purpose piston flow switch with a fixed set point and normally closed switch position. It has a PPS body, 9/16 in UNF connections, SPDT switching, and a 20 V DC contact rating. The manufacturer part number is FS-4, 122356.

Where to buy the GEMS SENSORS FS-4 flow switch worldwide?

You can source the GEMS SENSORS FS-4 flow switch through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations, ensuring the product reaches your facility reliably.

How to install a GEMS SENSORS piston flow switch?

Install the GEMS SENSORS piston flow switch in a horizontal pipe section with the arrow on the body aligned to flow direction. Use PTFE tape on the 9/16 in UNF threads to prevent leaks. Wire the SPDT contacts according to your control circuit, ensuring the 20 V DC rating is not exceeded.

Used in

Common applications for GEMS SENSORS
Burner management — GEMS SENSORS FS-4 piston flow switch for monitoring cooling water flow in industrial burners
Pump protection — GEMS SENSORS FS-380 high-pressure flow switch to detect loss of flow in pump systems
Process control — GEMS SENSORS 230500 thermal-dispersion flow switch for low-flow detection in chemical processes
Cooling systems — GEMS SENSORS RFS flow sight with remote output for visual and electrical flow indication in heat exchangers
Water treatment — GEMS SENSORS FT-110 turbine flow sensor for measuring flow rates in filtration systems
Hydraulic systems — GEMS SENSORS FS-500 polypropylene piston flow switch for corrosive fluid monitoring in hydraulic circuits

GEMS SENSORS Products

3G Electric supplies GEMS SENSORS general purpose piston flow switches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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