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

The MCDONNELL & MILLER FS6-W-1 is a 1 in inline flow switch for liquids, featuring a 1 in NPT connection and SPDT switching. It has a locked-rotor contact rating of 22.2 A at 240V AC.

SKU 3G-OTH-88564

Also listed as: FS6W1 · FS6 W 1

Brand
McDonnell & Miller
Item
Flow Switch: 1 in For Pipe Size, 1 in NPT, 1 in Connection Size
Category
Inline Switches for Liquids
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

McDonnell & Miller
Manufacturer Part Number
FS6-W-1
Type
NPT, SPDT
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 FS6-W-1 is a 1 in inline flow switch for liquids, featuring a 1 in NPT connection and SPDT switching. It has a locked-rotor contact rating of 22.2 A at 240V AC.

Frequently Asked Questions

What is the MCDONNELL & MILLER FS6-W-1 flow switch used for?

The MCDONNELL & MILLER FS6-W-1 is an inline flow switch for liquids, used to detect flow or no-flow conditions in piping systems. Common applications include HVAC, boiler protection, and industrial process control where a 1 in pipe size and SPDT switching are required.

What are the specifications of the MCDONNELL & MILLER FS6-W-1?

The FS6-W-1 is a 1 in inline flow switch for liquids with a 1 in NPT connection and SPDT contacts. Its locked-rotor contact rating is 22.2 A at 240V AC. The manufacturer part number is FS6-W-1, and it is designed for 1 in pipe size systems.

Where to buy the MCDONNELL & MILLER FS6-W-1 worldwide?

3G Electric supplies the MCDONNELL & MILLER FS6-W-1 flow switch worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

How to install the MCDONNELL & MILLER FS6-W-1 flow switch?

Install the FS6-W-1 in a horizontal pipe section with the flow arrow aligned to flow direction. Use thread sealant on the 1 in NPT connection and ensure electrical wiring matches the SPDT contact rating of 22.2 A at 240V AC. Consult the manufacturer's manual for torque and clearance requirements.

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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