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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 FS4-3 is a paddle-type insertion-style flow switch for liquids, designed for 1-inch pipe sizes with a 1-inch NPT connection. It features a contact rating of 44.4 A at 120V (locked rotor) for AC…

SKU 3G-OTH-93463

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 Specifications

McDonnell & Miller
Manufacturer Part Number
FS4-3
Type
NPT
NPT
1 in
For Pipe Size
1 in
Connection Size
1 in
Contact Rating (AC)
44.4 A @ 120V (Locked Rotor)
View Full Spec Sheet

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

Product Description

The MCDONNELL & MILLER FS4-3 is a paddle-type insertion-style flow switch for liquids, designed for 1-inch pipe sizes with a 1-inch NPT connection. It features a contact rating of 44.4 A at 120V (locked rotor) for AC applications.

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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