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Mcdonnell & Miller Series FS4-3 General Purpose Liquid Flow Switches
Mcdonnell & MillerFlow Switches

Mcdonnell & Miller Series FS4-3 General Purpose Liquid Flow Switches

McDonnell & Miller Flow Switches.

SKU 3G-OTH-02753

Also listed as: FS43 · FS4 3

Brand
Mcdonnell & Miller
Item
Series FS4-3 General Purpose 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-02753 flow switch used for?

The McDonnell & Miller 3G-OTH-02753 is a 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-02753?

The 3G-OTH-02753 features a 1-inch NPT connection, two electrical knock-outs for wiring from either end, and a sensitivity adjusting screw for easy flow adjustment. It has a single pole, double throw (SPDT) snap-action switch rated for general-purpose flow detection.

Where to buy the McDonnell & Miller 3G-OTH-02753 in Singapore?

You can source the McDonnell & Miller 3G-OTH-02753 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 item.

How to install the McDonnell & Miller 3G-OTH-02753 flow switch?

Install the 3G-OTH-02753 in a horizontal pipe section with the flow arrow aligned to flow direction. Use the sensitivity adjusting screw to set the actuation point. Wire the SPDT switch through the knock-outs per your control circuit. Always follow local electrical codes and the manufacturer's manual.

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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Cross-referenced by specification & description
This Siemens 2-way flanged zone valve features a 3/4 in flanged port connection, 5.9 Cv flow rate, and 24V AC/DC actuator voltage. It operates with spring return, normally closed action, and proportional signal for modulating control. Suitable for regulating water or glycol flow in HVAC and industrial fluid control systems
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This Siemens 2-way flanged zone valve features a 3/4 in flanged port connection, 5.9 Cv flow rate, and 24V AC/DC actuator voltage. It operates with spring return, normally closed action, and proportional signal for modulating control. Suitable for regulating water or glycol flow in HVAC and industrial fluid control systems
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This Siemens magnetic valve is a 2-way, spring return, normally closed (NC) valve with a floating signal. It features a 2 in Union NPT port connection and operates on 20 to 30V DC actuator voltage. Suitable for on/off or floating control in HVAC and industrial fluid systems, it provides fail-safe operation upon power loss
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