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GEMS SENSORS Liquid Flow Switch: Brass, 1 in FNPT, 1 in Connection Size, FNPT, -20°F – 212°F - Flow Sights with Remote Output
GEMS SENSORSFlow Sights with Remote Output

GEMS SENSORS Liquid Flow Switch: Brass, 1 in FNPT, 1 in Connection Size, FNPT, -20°F – 212°F

The GEMS SENSORS Liquid Flow Switch: Brass is a flow sight with remote output, featuring a 1 in FNPT connection and SPDT switch type. It is normally open, CE Certified, and has a wetted material of ceramic. The…

SKU 3G-OTH-90864

Brand
GEMS SENSORS
Item
Liquid Flow Switch: Brass, 1 in FNPT, 1 in Connection Size, FNPT, -20°F – 212°F
Category
Flow Sights with Remote Output
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Technical Specifications

GEMS SENSORS
Manufacturer Part Number
RFS, 181688
Type
FNPT, -20°F – 212°F, SPDT
FNPT
1 in
Standards
CE Certified
Switch Type
SPDT
Connection Size
1 in
Connection Type
FNPT
Switch Position
Normally Open
Wetted Material
Ceramic
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GEMS SENSORS Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The GEMS SENSORS Liquid Flow Switch: Brass is a flow sight with remote output, featuring a 1 in FNPT connection and SPDT switch type. It is normally open, CE Certified, and has a wetted material of ceramic. The operating temperature range is -20°F to 212°F, with the manufacturer part number RFS, 181688.

Frequently Asked Questions

What is the GEMS SENSORS RFS liquid flow switch used for?

The GEMS SENSORS RFS liquid flow switch is used to detect and signal the presence or absence of liquid flow in industrial piping systems. It is commonly applied in HVAC, water treatment, and process control to protect pumps and equipment from dry-run or low-flow conditions.

What are the specifications of the GEMS SENSORS RFS flow switch?

The GEMS SENSORS RFS flow switch has a 1 in FNPT brass body, SPDT switch type, normally open position, and ceramic wetted material. It is CE Certified, operates from -20°F to 212°F, and carries manufacturer part number RFS, 181688.

Where to buy the GEMS SENSORS RFS flow switch worldwide?

3G Electric supplies the GEMS SENSORS RFS flow switch worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this CE Certified SPDT flow switch.

How to install a GEMS SENSORS RFS liquid flow switch?

Install the GEMS SENSORS RFS flow switch in a horizontal pipe section with the arrow aligned to flow direction. Use PTFE tape on the 1 in FNPT threads, ensure the ceramic wetted material is compatible with the fluid, and wire the SPDT contacts per your control circuit. Test for proper actuation at the set point.

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 flow sights with remote output. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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GEMS SENSORS Liquid Flow Switch: Brass, 3/4 in FNPT, 3/4 in Connection Size, FNPT, -20°F – 212°F (MPN RFS, 180395). Key specifications — Switch Type: SPDT; Switch Position: Normally Closed; Brand: GEMS SENSORS; Connection Type: FNPT; Standards: UL Listed; Wetted Material: Ceramic.
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GEMS SENSORS Liquid Flow Switch: Brass, 1/2 in FNPT, 1/2 in Connection Size, FNPT, -20°F – 212°F (MPN RFS, 156268). Key specifications — Switch Type: SPDT; Switch Position: Normally Closed; Brand: GEMS SENSORS; Connection Type: FNPT; Standards: UL Listed; Wetted Material: Viton.
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GEMS SENSORS Liquid Flow Switch: Brass, 1/4 in FNPT, 1/4 in Connection Size, FNPT, -20°F – 212°F (MPN RFS, 156265). Key specifications — Switch Type: SPDT; Switch Position: Normally Open; Brand: GEMS SENSORS; Connection Type: FNPT; Standards: UL Listed; Wetted Material: Viton.
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