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Mcdonnell & Miller Series FS1 High Sensitivity Liquid Flow Switches
Mcdonnell & MillerFlow Switches

Mcdonnell & Miller Series FS1 High Sensitivity Liquid Flow Switches

McDonnell & Miller Flow Switches.

SKU 3G-OTH-02752

Brand
Mcdonnell & Miller
Item
Series FS1 High Sensitivity Liquid Flow Switches
Category
Flow Switches
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 Documents

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

Product Description

McDonnell & Miller Flow Switches.

Frequently Asked Questions

What is the McDonnell & Miller FS1 flow switch used for?

The McDonnell & Miller FS1 flow switch detects liquid flow or no-flow in piping systems. It is commonly used in HVAC, boiler, and industrial process applications to interlock pumps, alarms, or burners when flow is present or lost.

What are the specifications of the McDonnell & Miller FS1 flow switch?

The FS1 features a 1/2" NPT connection, high flow capacity, and an in-line configuration that eliminates the need for a pipe tee. It includes a single-pole, double-throw snap switch and a sealed switch compartment for reliable operation.

Where to buy the McDonnell & Miller FS1 in Singapore?

You can source the McDonnell & Miller FS1 flow switch through 3G Electric in Singapore. We handle logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this item.

How to install the McDonnell & Miller FS1 flow switch?

Install the FS1 in a horizontal pipe with the flow arrow aligned to flow direction. Use a 1/2" NPT fitting and ensure the switch is wired per the SPDT contact rating. Follow standard piping practices and verify flow before commissioning.

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 flow switches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
SMC
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Inline solid state auto switch for pneumatic cylinder position detection. PNP output with M12-4Pin connector. IP67 rated. Used in industrial automation to provide piston position feedback to controllers
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Inline solid state auto switch for pneumatic cylinder position sensing. PNP output, M8-3Pin connector, 3 wires, IP67 rated. Used to detect piston position in automated machinery
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The SMC D-F7PL is an inline solid state auto switch with PNP output, designed for pneumatic cylinder position sensing in automated machinery. It features IP67 protection for use in harsh environments, a maximum current draw of 80 mA, and a 3-wire connection for integration with PLCs or controllers
SMC
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Inline solid state auto switch for pneumatic cylinder position sensing. PNP output, M8 3-pin connector, 3 wires. IP67 rated. Maximum load current 80 mA. Used in industrial automation to detect piston position and provide feedback to controllers
Inline solid state auto switch for pneumatic cylinder position sensing. Features PNP output, M12-4Pin connector, and IP67 rating. Maximum current consumption 80 mA or less. Suitable for automated machinery and industrial control systems
SMC
Inline solid state auto switch for pneumatic cylinder position sensing. Features PNP output, M12-4Pin connector, and IP67 rating. Maximum current consumption 80 mA or less. Suitable for automated machinery and industrial control systems
SMC
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Inline solid state auto switch with PNP output, M8-3Pin connector, and IP67 rating. Designed for direct inline mounting to detect cylinder piston position in pneumatic systems. Provides a switching signal for automated machinery control

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