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

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

The MCDONNELL & MILLER FS8-W is a paddle-type flow switch for liquids, designed for inline installation in 1-inch pipe systems. It features a 1-inch NPT connection and an AC contact rating of 22.2 A at 240V (locked…

SKU 3G-OTH-88648

Also listed as: FS8W · FS8 W

Brand
McDonnell & Miller
Item
Flow Switch: Paddle, 1 in For Pipe Size, 1 in NPT, 1 in Connection Size
Category
Inline Switches for Liquids
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Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment
Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

McDonnell & Miller
Manufacturer Part Number
FS8-W
Type
NPT
NPT
1 in
For Pipe Size
1 in
Connection Size
1 in
Contact Rating (AC)
22.2 A @ 240V (Locked Rotor)

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

Product Description

The MCDONNELL & MILLER FS8-W is a paddle-type flow switch for liquids, designed for inline installation in 1-inch pipe systems. It features a 1-inch NPT connection and an AC contact rating of 22.2 A at 240V (locked rotor). This switch provides flow detection for industrial liquid applications.

Frequently Asked Questions

What is the McDonnell & Miller FS8-W flow switch used for?

The McDonnell & Miller FS8-W is a paddle-type flow switch that detects liquid flow in 1-inch pipe systems. It is used in industrial applications such as pump protection, boiler low-water cutoff, and cooling water monitoring to trigger alarms or shut down equipment when flow stops.

What are the specifications of the McDonnell & Miller FS8-W?

The FS8-W has a 1-inch NPT connection for 1-inch pipe size. Its AC contact rating is 22.2 A at 240V (locked rotor). The switch is designed for inline installation in liquid systems and is manufactured by McDonnell & Miller under part number FS8-W.

Where to buy the McDonnell & Miller FS8-W worldwide?

3G Electric supplies the McDonnell & Miller FS8-W flow switch to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this paddle-type flow switch.

How to install the McDonnell & Miller FS8-W flow switch?

Install the FS8-W in a horizontal pipe section with the paddle oriented correctly for flow direction. Ensure the pipe is 1-inch NPT and the switch is wired per local codes. Follow McDonnell & Miller's generic guidelines for paddle-type switches: avoid overtightening and verify flow detection after installation.

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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