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

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

McDonnell & Miller Flow Switches.

SKU 3G-OTH-02758

Also listed as: FS74E · FS7 4E

Brand
Mcdonnell & Miller
Item
Series FS7-4E 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-02758 flow switch used for?

The McDonnell & Miller 3G-OTH-02758 is a magnetic flow switch used in industrial piping systems to detect liquid flow or no-flow conditions. It is commonly applied in HVAC, boiler, and process control systems to activate alarms, pumps, or burners when flow starts or stops.

What are the specifications of the McDonnell & Miller 3G-OTH-02758?

The 3G-OTH-02758 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 with a sensitivity adjusting screw. The switch is rated for general-purpose flow detection in liquid lines.

Where to buy the McDonnell & Miller 3G-OTH-02758 in Singapore?

You can source the McDonnell & Miller 3G-OTH-02758 flow switch through 3G Electric in Singapore. We handle logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this McDonnell & Miller model.

How to install the McDonnell & Miller 3G-OTH-02758 flow switch?

Install the 3G-OTH-02758 in a horizontal pipe section with the switch housing upright. Ensure flow direction matches the arrow on the body. Adjust the sensitivity screw to set the flow-actuation point. Follow standard piping practices and consult the manufacturer's manual for wiring the SPDT switch.

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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