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Mcdonnell & Miller Series FS7-4 Industrial Liquid Flow Switches
Mcdonnell & MillerFlow Switches

Mcdonnell & Miller Series FS7-4 Industrial Liquid Flow Switches

McDonnell & Miller Flow Switches.

SKU 3G-OTH-02757

Also listed as: FS74 · FS7 4

Brand
Mcdonnell & Miller
Item
Series FS7-4 Industrial 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 3G-OTH-02757 flow switch used for?

The McDonnell & Miller 3G-OTH-02757 is used to detect liquid flow or no-flow conditions in industrial piping systems. It is commonly applied in HVAC, boiler, and process control systems to interlock pumps, alarms, or burners when flow is lost or restored.

What are the specifications of the McDonnell & Miller 3G-OTH-02757?

The 3G-OTH-02757 features a 1 1/4 inch NPT brass body with sealed tube construction. It uses a single pole, double throw snap switch and a magnetic switching mechanism that eliminates mechanical linkages. The switch is rated for general-purpose flow detection in liquid lines.

Where to buy the McDonnell & Miller 3G-OTH-02757 in Singapore?

3G Electric supplies the McDonnell & Miller 3G-OTH-02757 flow switch to customers 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 3G-OTH-02757 flow switch?

Install the 3G-OTH-02757 in a horizontal pipe run with the flow arrow aligned to the direction of flow. Ensure the pipe is fully filled with liquid and free of air pockets. Wire the SPDT switch according to your control circuit. Follow McDonnell & Miller's installation manual for proper paddle selection and adjustment.

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
TELEMECANIQUE SENSORS Water Pump Switch: Std, 5 psi – 65 psi, 1/4" FNPS, 20 psi / 40 psi ON/OFF (MPN 9013FSG2J20U)
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High precision vacuum pressure switch from the ZSE20B(F) series with a 1/8 in port size. Operates on 12 to 24V DC and offers 1 Output/2 Output NPN/PNP open collector configurations. Includes a 4-Pin Snap-In Plug connection. Used for precise vacuum pressure monitoring in industrial automation applications such as pick-and-place systems and packaging
High precision vacuum pressure switch with 1/8 in port size, 1 Output/2 Output NPN/PNP open collector configuration, operating on 12 to 24V DC. Features a 4-Pin Snap-In Plug connection. Suitable for precise vacuum pressure monitoring in industrial automation applications
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The SMC ZSE20B-R-M-C6L-W is a high precision vacuum pressure switch from the ZSE20B(F) series. It features a 6 mm port size and offers 1 Output/2 Output NPN/PNP Open Collector configurations. This switch is used for precise vacuum pressure monitoring in industrial automation applications such as pick-and-place, packaging, and semiconductor equipment
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The SMC ZSE20B-R-M-C6L-W is a high precision vacuum pressure switch from the ZSE20B(F) series. It features a 6 mm port size and offers 1 Output/2 Output NPN/PNP Open Collector configurations. This switch is used for precise vacuum pressure monitoring in industrial automation applications such as pick-and-place, packaging, and semiconductor equipment
High precision vacuum pressure switch from the ZSE20B(F) series with 1/8 in port size and 4-pin snap-in plug. Operates on 12 to 24V DC and provides 1 output/2 output NPN/PNP open collector configurations. Suitable for monitoring and controlling vacuum or pressure levels in pneumatic systems
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High precision vacuum pressure switch from the ZSE20B(F) series with 1/8 in port size and 4-pin snap-in plug. Operates on 12 to 24V DC and provides 1 output/2 output NPN/PNP open collector configurations. Suitable for monitoring and controlling vacuum or pressure levels in pneumatic systems
High precision vacuum pressure switch from the ZSE20B(F) series with a 1/8 in port size. Features 1 Output/2 Output NPN/PNP open collector configurations, operates on 12 to 24V DC, and includes a 4-Pin Snap-In Plug connection. Suitable for monitoring and controlling vacuum levels in pneumatic systems
SMC
High precision vacuum pressure switch from the ZSE20B(F) series with a 1/8 in port size. Features 1 Output/2 Output NPN/PNP open collector configurations, operates on 12 to 24V DC, and includes a 4-Pin Snap-In Plug connection. Suitable for monitoring and controlling vacuum levels in pneumatic systems

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