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MCDONNELL & MILLER Flow Switch: 1/2 in For Pipe Size, 1/2 in NPT, 1/2 in Connection Size - Inline Switches for Liquids
McDonnell & MillerInline Switches for Liquids

MCDONNELL & MILLER Flow Switch: 1/2 in For Pipe Size, 1/2 in NPT, 1/2 in Connection Size

The MCDONNELL & MILLER FS-1 is an inline flow switch for liquids designed for a 1/2 in pipe size with 1/2 in NPT connections. It features a SPDT switch with a contact rating of 22.2 A at 240V (locked rotor). This…

SKU 3G-OTH-88471

Brand
McDonnell & Miller
Item
Flow Switch: 1/2 in For Pipe Size, 1/2 in NPT, 1/2 in Connection Size
Category
Inline Switches for Liquids
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Technical Specifications

McDonnell & Miller
Manufacturer Part Number
FS-1
Type
NPT, SPDT
NPT
1/2 in
For Pipe Size
1/2 in
Connection Size
1/2 in
Contact Rating (AC)
22.2 A @ 240V (Locked Rotor)
View Full Spec Sheet

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McDonnell & Miller Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The MCDONNELL & MILLER FS-1 is an inline flow switch for liquids designed for a 1/2 in pipe size with 1/2 in NPT connections. It features a SPDT switch with a contact rating of 22.2 A at 240V (locked rotor). This switch provides flow detection for liquid systems.

Frequently Asked Questions

What is the McDonnell & Miller FS-1 flow switch used for?

The McDonnell & Miller FS-1 is an inline flow switch for liquids that detects flow in 1/2 in pipe systems. It is commonly used in HVAC, boiler, and industrial liquid circuits to signal flow or no-flow conditions, protecting equipment from damage due to insufficient flow.

What are the specifications of the McDonnell & Miller FS-1?

The FS-1 has a 1/2 in NPT connection, SPDT switch type, and a contact rating of 22.2 A at 240V (locked rotor). It is designed for 1/2 in pipe size and is manufactured by McDonnell & Miller. These specs ensure reliable flow detection in liquid systems.

Where to buy the McDonnell & Miller FS-1 worldwide?

3G Electric supplies the McDonnell & Miller FS-1 flow switch worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this part.

How to install the McDonnell & Miller FS-1 flow switch?

Install the FS-1 in a horizontal pipe section with flow direction matching the arrow on the body. Use thread sealant on the 1/2 in NPT connections and ensure the SPDT wiring matches your control circuit. Always follow local electrical codes and the manufacturer's guidelines.

Used in

Common applications for McDonnell & Miller
Steam boiler low-water cutoff — McDonnell & Miller inline flow switches (e.g., FS-1) for automatic burner shutdown
Cooling water flow monitoring — McDonnell & Miller insertion-style switches (e.g., FS4-3D) in large-diameter pipes
Hazardous-area process lines — McDonnell & Miller FS7-4E with NEMA 7/9 enclosure for Class I, Div 1 locations
HVAC chilled water systems — McDonnell & Miller FS6-1 inline switch for pump flow verification
Industrial wastewater treatment — McDonnell & Miller FS4-3S stainless steel switch for corrosive fluid flow detection
Boiler feedwater control — McDonnell & Miller FS8-WJ with BSP connections for international installations

McDonnell & Miller Products

3G Electric supplies McDonnell & Miller inline switches for liquids. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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