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

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

Note: listed by manufacturer as obsolete/discontinued.

SKU 3G-OTH-02754

Also listed as: FS43T · FS4 3T

Brand
Mcdonnell & Miller
Item
Series FS4-3T 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

Note: listed by manufacturer as obsolete/discontinued.

Frequently Asked Questions

What is the McDonnell & Miller 3G-OTH-02754 flow switch used for?

The McDonnell & Miller 3G-OTH-02754 is a flow switch used to detect liquid flow in piping systems. Its in-line configuration eliminates the need for a pipe tee, making it suitable for industrial applications such as pump protection, boiler control, and process monitoring where flow verification is required.

What are the specifications of the McDonnell & Miller 3G-OTH-02754?

The 3G-OTH-02754 is available in 3/4 NPT and 1 NPT sizes. It includes paddles for low, medium, or high flow detection and has two electrical connections. Note that this model is listed as obsolete/discontinued by the manufacturer, so availability is limited to existing stock.

Where to buy the McDonnell & Miller 3G-OTH-02754 in Singapore?

You can source the McDonnell & Miller 3G-OTH-02754 through 3G Electric in Singapore. We provide industrial equipment sourcing, handle logistics and customs clearance, and arrange delivery to your facility. Contact us for current availability and lead time on this discontinued model.

How to install the McDonnell & Miller 3G-OTH-02754 flow switch?

Install the 3G-OTH-02754 in a horizontal pipe section with the flow arrow aligned to flow direction. Select the appropriate paddle for your flow range. Ensure electrical connections match the switch rating. Follow standard piping practices and consult the manufacturer's manual for torque and wiring details.

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
Siemens
Siemens
2-way, spring return, normally closed zone valve with 3/4 in Union NPT connections and 24V AC/DC floating signal actuator. Used in HVAC systems for regulating fluid flow in piping networks
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
Siemens
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
3-way flanged zone valve with 3 in flanged port connection and 24V AC actuator. Spring return normally closed (NC) operation with floating signal control for fail-safe shutoff in HVAC and industrial water systems
Siemens
3-way flanged zone valve with 3 in flanged port connection and 24V AC actuator. Spring return normally closed (NC) operation with floating signal control for fail-safe shutoff in HVAC and industrial water systems
Siemens
Siemens
Two-way, spring return, normally closed zone valve with 1 in Union NPT connections and 24V AC floating signal actuator. Used in hydronic HVAC systems to regulate fluid flow in heating or cooling zones
Siemens
Siemens
2-way, spring return, normally closed zone valve with 1-1/4 in Union NPT connections. Operates on 24V AC floating signal. Suitable for regulating fluid flow in HVAC zone control applications
Siemens
Siemens
This Siemens 2-way flanged zone valve features a 1/2 in flanged port connection and a 24V AC/DC actuator. It is spring return normally closed (NC) and accepts a proportional signal for modulating flow. Used in hydronic heating and cooling systems for zone control

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