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MCDONNELL & MILLER General Purpose Switch: Paddle, 1 in/6 in For Pipe Size - Insertion-Style Switches for Liquids
McDonnell & MillerInsertion-Style Switches for Liquids

MCDONNELL & MILLER General Purpose Switch: Paddle, 1 in/6 in For Pipe Size

The McDonnell & Miller FS251 is a general-purpose, insertion-style paddle switch for liquids, designed for use with a 6-inch pipe size. It features a brass body with a 1-inch NPT connection and an AC contact rating…

SKU 3G-OTH-93528

Also listed as: FS 251 · FS-251

Brand
McDonnell & Miller
Item
General Purpose Switch: Paddle, 1 in/6 in For Pipe Size
Category
Insertion-Style Switches for Liquids
Available to Order
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Local availability & support — the Philippines

Delivery
5–8 business days door-to-door; Bureau of Customs clearance typically 2–4 business days.
Payment
Invoicing in PHP or USD. Bank transfer and corporate PO accepted.
Ships to
Manila, Quezon City, Cebu, Davao, Batangas

Technical Specifications

McDonnell & Miller
Manufacturer Part Number
FS251
Type
1 in/6 in For Pipe Size, Brass, NPT
NPT
1 in
For Pipe Size
6 in
Contact Rating (AC)
44.4 A @ 120V (Locked Rotor)

Technical Documents

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

Product Description

The McDonnell & Miller FS251 is a general-purpose, insertion-style paddle switch for liquids, designed for use with a 6-inch pipe size. It features a brass body with a 1-inch NPT connection and an AC contact rating of 44.4 A at 120V (locked rotor). This switch is suitable for liquid level detection in industrial applications.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the McDonnell & Miller FS251 used for?

The McDonnell & Miller FS251 is an insertion-style paddle switch for liquid level detection in industrial piping systems. It is designed for 6-inch pipe sizes and triggers an electrical signal when liquid flow or level changes, commonly used in HVAC, boiler, and process control applications.

What are the specifications of the McDonnell & Miller FS251?

The FS251 has a brass body with a 1-inch NPT connection, fits 6-inch pipe, and carries a locked-rotor AC contact rating of 44.4 A at 120V. It is a general-purpose paddle switch for liquids, manufactured by McDonnell & Miller under MPN FS251.

Where to buy the McDonnell & Miller FS251 worldwide?

3G Electric supplies the McDonnell & Miller FS251 worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time; we source and deliver this insertion-style switch to any country.

How to install the McDonnell & Miller FS251 paddle switch?

Install the FS251 by threading the 1-inch NPT brass body into a compatible fitting on a 6-inch pipe. Ensure the paddle is oriented correctly for flow direction. Follow standard electrical safety practices for wiring the 44.4 A contact rating. Consult the manufacturer's manual for torque and positioning details.

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 insertion-style 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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