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GEMS SENSORS General Purpose Piston Flow Switch - General Purpose Piston Flow Switches
GEMS SENSORSGeneral Purpose Piston Flow Switches

GEMS SENSORS General Purpose Piston Flow Switch

The GEMS SENSORS Liquid Flow Switch: Piston is a general purpose piston flow switch with a fixed set point and a normally open switch position. It features a 9/16 in UNF connection size, PPS construction, and an SPDT…

SKU 3G-OTH-89337

Also listed as: FS4122355 · FS 4 122355 · FS-4-122355

Brand
GEMS SENSORS
Item
General Purpose Piston Flow Switch
Part Number
FS-4, 122355
Category
General Purpose Piston Flow Switches
Available to Order
Also known as:FS-4, 122355GEMS SENSORS
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Technical Specifications

GEMS SENSORS
Manufacturer Part Number
FS-4, 122355
Type
PPS, UNF, SPDT, Fixed
UNF
9/16 in
Set Point Type
Fixed
Connection Size
9/16 in
Switch Position
Normally Open
Contact Rating (DC)
20 V

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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 open switch position. It features a 9/16 in UNF connection size, PPS construction, and an SPDT contact configuration. The switch has a DC contact rating of 20 V and is identified by manufacturer part numbers FS-4 and 122355.

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 the presence or absence of liquid flow in a pipe. It is commonly applied in industrial cooling systems, lubrication circuits, and process control to trigger an alarm or shut down equipment when flow stops.

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 open switch position. It has a 9/16 in UNF connection size, PPS construction, SPDT contacts, and a DC contact rating of 20 V. The manufacturer part numbers are FS-4 and 122355.

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. Contact us for availability and lead time on this item.

How to install a GEMS SENSORS piston flow switch?

Install the GEMS SENSORS piston flow switch in a vertical or horizontal pipe section with the arrow on the body aligned to flow direction. Ensure the 9/16 in UNF connection is properly sealed. Wire the SPDT contacts according to your control circuit, respecting the 20 V DC rating. Test the set point after installation.

Used in

Common applications for GEMS SENSORS
Cooling water systems — Gems Sensors flow sights with remote output (e.g., 1AMB2) monitor flow to critical equipment and signal alarms.
Lubrication lines — Gems Sensors flow indicators (e.g., 1AMD3) provide visual confirmation of oil flow to bearings and gears.
Process water monitoring — Gems Sensors flow sights (e.g., 1AMB9) verify flow in water treatment and chemical dosing systems.
HVAC systems — Gems Sensors flow switches (e.g., 1AMB5) detect flow in chilled water and condenser loops for pump control.
Food and beverage — Gems Sensors flow sights with stainless steel bodies (e.g., 1AMD4) are used in clean-in-place (CIP) systems for flow verification.
Power generation — Gems Sensors flow sights (e.g., 1AMB6) monitor cooling water and lube oil flow in turbines and generators.
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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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