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MCDONNELL & MILLER Flow Switch: Paddle, 1 in For Pipe Size, 1 in NPT, 1 in Connection Size - Insertion-Style Switches for Liquids
McDonnell & MillerInsertion-Style Switches for Liquids

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

The MCDONNELL & MILLER FS4-3D is a paddle-type flow switch for liquids, designed as an insertion-style switch for 1 in pipe sizes. It features a 1 in NPT connection and an AC contact rating of 22.2 A at 240V (locked…

SKU 3G-OTH-93432

Also listed as: FS43D · FS4 3D

Brand
McDonnell & Miller
Item
Flow Switch: Paddle, 1 in For Pipe Size, 1 in NPT, 1 in Connection Size
Category
Insertion-Style Switches for Liquids
Available to Order
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Technical specs
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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
FS4-3D
Type
NPT
NPT
1 in
For Pipe Size
1 in
Connection Size
1 in
Contact Rating (AC)
22.2 A @ 240V (Locked Rotor)

Technical Documents

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

Product Description

The MCDONNELL & MILLER FS4-3D is a paddle-type flow switch for liquids, designed as an insertion-style switch for 1 in pipe sizes. It features a 1 in NPT connection and an AC contact rating of 22.2 A at 240V (locked rotor). This switch is used to detect liquid flow in industrial piping systems.

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 FS4-3D flow switch used for?

The MCDONNELL & MILLER FS4-3D is a paddle-type flow switch used to detect liquid flow in industrial piping systems. It is commonly applied in HVAC, boiler, and process control applications to ensure flow exists before equipment operation, protecting pumps and heaters from dry-run damage.

What are the specifications of the MCDONNELL & MILLER FS4-3D flow switch?

The MCDONNELL & MILLER FS4-3D is an insertion-style paddle flow switch for 1 in pipe size with a 1 in NPT connection. Its AC contact rating is 22.2 A at 240V (locked rotor). The manufacturer part number is FS4-3D, and it is designed for liquid service in industrial environments.

Where to buy the MCDONNELL & MILLER FS4-3D flow switch worldwide?

3G Electric supplies the MCDONNELL & MILLER FS4-3D flow switch worldwide. As a global industrial equipment distributor since 1990, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this paddle-type flow switch.

How to install the MCDONNELL & MILLER FS4-3D flow switch?

Install the MCDONNELL & MILLER FS4-3D by inserting the paddle into a 1 in NPT fitting on the pipe. Ensure flow direction matches the arrow on the switch body. Wire the contacts per the AC rating (22.2 A at 240V locked rotor) and test for proper actuation at desired flow rates.

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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