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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 FS4-3T3-1 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 3.7 A at 240V full load.

SKU 3G-OTH-88606

Also listed as: FS43T31 · FS4 3T3 1

Brand
McDonnell & Miller
Item
Flow Switch: Paddle, 1 in For Pipe Size, 1 in NPT, 1 in Connection Size
Category
Inline 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
FS4-3T3-1
Type
NPT
NPT
1 in
For Pipe Size
1 in
Connection Size
1 in
Contact Rating (AC)
3.7 A @ 240V (Full Load)

Technical Documents

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

Product Description

The MCDONNELL & MILLER FS4-3T3-1 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 3.7 A at 240V full load.

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 FS4-3T3-1 flow switch used for?

The McDonnell & Miller FS4-3T3-1 is a paddle-type flow switch for liquids, used to detect flow or no-flow conditions in 1-inch pipe systems. Common applications include pump protection, boiler low-water cutoff, and cooling water monitoring in industrial HVAC, process, and power generation systems.

What are the specifications of the McDonnell & Miller FS4-3T3-1?

The FS4-3T3-1 is a 1-inch NPT inline paddle flow switch for liquids. It has a 1-inch pipe size, 1-inch NPT connection, and an AC contact rating of 3.7 A at 240V full load. The manufacturer part number is FS4-3T3-1, and it is designed for 1-inch pipe systems.

Where to buy the McDonnell & Miller FS4-3T3-1 worldwide?

3G Electric supplies the McDonnell & Miller FS4-3T3-1 flow switch to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this genuine McDonnell & Miller part.

How to install a McDonnell & Miller FS4-3T3-1 paddle flow switch?

Install the FS4-3T3-1 in a horizontal pipe section with the paddle oriented against flow direction. Use thread sealant on the 1-inch NPT connection and ensure the pipe is fully drained before installation. Wire the switch per the contact rating (3.7 A at 240V AC) and test for proper actuation at desired flow rate.

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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