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

The MCDONNELL & MILLER Flow Switch is an inline switch for liquids designed for a 1 in pipe size. This brass unit features a 1 in NPT connection and an SPDT switch with a contact rating of 22.2 A @ 240V (Locked…

SKU 3G-OTH-88589

Brand
McDonnell & Miller
Item
Flow Switch: 1 in For Pipe Size, Brass, 1 in NPT, 1 in Connection Size
Category
Inline Switches for Liquids
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Technical Specifications

McDonnell & Miller
Manufacturer Part Number
FS5-1
Type
Brass, NPT, SPDT
NPT
1 in
For Pipe Size
1 in
Connection Size
1 in
Contact Rating (AC)
22.2 A @ 240V (Locked Rotor)
View Full Spec Sheet

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

Product Description

The MCDONNELL & MILLER Flow Switch is an inline switch for liquids designed for a 1 in pipe size. This brass unit features a 1 in NPT connection and an SPDT switch with a contact rating of 22.2 A @ 240V (Locked Rotor). It is identified by manufacturer part number FS5-1.

Frequently Asked Questions

What is the MCDONNELL & MILLER FS5-1 flow switch used for?

The MCDONNELL & MILLER FS5-1 flow switch is used to detect liquid flow or no-flow conditions in piping systems. It is commonly applied in HVAC, boiler, and industrial process lines to interlock pumps, alarms, or burners when flow stops or starts.

What are the specifications of the MCDONNELL & MILLER FS5-1 flow switch?

The FS5-1 is a brass inline flow switch for 1 in pipe size with a 1 in NPT connection. It features an SPDT switch rated at 22.2 A @ 240V (Locked Rotor). The manufacturer part number is FS5-1, and it is designed for liquid service.

Where to buy the MCDONNELL & MILLER FS5-1 flow switch worldwide?

3G Electric supplies the MCDONNELL & MILLER FS5-1 flow switch worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time.

How to install the MCDONNELL & MILLER FS5-1 flow switch?

Install the FS5-1 in a horizontal pipe section with the flow arrow aligned to flow direction. Use thread sealant on the 1 in NPT connection. Wire the SPDT contacts per your control circuit, ensuring the contact rating of 22.2 A @ 240V is not exceeded.

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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