Send a part number, a photo, or a whole BOM — we supply it and stand behind it. EXW Singapore — collect from our office.

3G Electric
Mcdonnell & Miller Series FS7-4W Industrial Liquid Flow Switches
Mcdonnell & MillerFlow Switches

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

McDonnell & Miller Flow Switches.

SKU 3G-OTH-02759

Brand
Mcdonnell & Miller
Item
Series FS7-4W Industrial Liquid Flow Switches
Part Number
FS74W
Category
Flow Switches
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineerMessage via Telegram
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
EXW Singapore
Collect or forward from our office
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.

Technical Specifications

Mcdonnell & Miller
Manufacturer Part Number
FS74W

Technical Documents

No technical documents available for this product.
Request documentation →
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

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

Product Description

McDonnell & Miller Flow Switches.

Frequently Asked Questions

What is the McDonnell & Miller FS7-4W flow switch used for?

The McDonnell & Miller FS7-4W is a brass flow switch with sealed tube construction used to detect liquid flow or no-flow conditions in piping systems. It is commonly applied in HVAC, boiler, and industrial process control to interlock pumps, alarms, or burners.

What are the specifications of the McDonnell & Miller FS7-4W?

The FS7-4W features a single pole, double throw snap switch and a magnetic switching mechanism that eliminates the need for bellows. It has a brass body with sealed tube construction and is designed for sensitivity adjustment. Contact 3G Electric for full technical data.

Where to buy the McDonnell & Miller FS7-4W in Singapore?

3G Electric supplies the McDonnell & Miller FS7-4W flow switch to Singapore. We handle sourcing, logistics, customs clearance, and delivery to your facility. Contact our team for pricing and lead time on this item.

How to install the McDonnell & Miller FS7-4W flow switch?

Install the FS7-4W in a horizontal pipe section with the flow arrow aligned to flow direction. Ensure the switch is wired according to the voltage and load ratings. Adjust sensitivity per the manufacturer's guidelines. Always isolate power before installation.

Used in

Common applications for Mcdonnell & Miller
Boiler systems — McDonnell & Miller FS4-3T3-1 flow switch for low-water cutoff and pump protection in 1-inch piping.
Pump control — McDonnell & Miller FS8-W flow switch for detecting flow in 1-inch lines to prevent dry running.
HVAC cooling water — McDonnell & Miller FS6-3/4 flow switch for monitoring flow in 3/4-inch chilled water circuits.
Process piping — McDonnell & Miller FS5-3/4 brass flow switch for hot water applications up to 250°F.
Industrial liquid monitoring — McDonnell & Miller FS6-W-1 flow switch for 1-inch lines with high locked-rotor rating.
Small pipe systems — McDonnell & Miller FS-1 flow switch for 1/2-inch lines in liquid circuits requiring flow detection.
Not sure this is the right part? Photo-identify it→

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.

You might also need

Burners & Combustion →Pumps & Compressors →Spare Parts →All Products →

More from McDonnell & Miller

View all McDonnell & Miller parts →
In-line configuration eliminates need for a pipe tee High flow capacity 1 2 NPT Single pole, double throw snap switch Switch compartment is completely
McDonnell & Miller
In-line configuration eliminates need for a pipe tee High flow capacity 1 2 NPT Single pole, double throw snap switch Switch compartment is completely
In-line configuration eliminates need for a pipe tee Sizes available 3 4 NPT 1 NPT Paddles available for low, medium or high flow Two electrical
McDonnell & Miller
In-line configuration eliminates need for a pipe tee Sizes available 3 4 NPT 1 NPT Paddles available for low, medium or high flow Two electrical
For low velocity applications Paddle fits 8 (203mm) minimum duct size Two electrical knock-outs allow connection from either end Brass, steel and aluminum
McDonnell & Miller
For low velocity applications Paddle fits 8 (203mm) minimum duct size Two electrical knock-outs allow connection from either end Brass, steel and aluminum
For general purpose applications with medium and high velocity requirements Paddle fits 8 (203mm) minimum duct size, or 6 (152mm) if trimmed Brass
McDonnell & Miller
For general purpose applications with medium and high velocity requirements Paddle fits 8 (203mm) minimum duct size, or 6 (152mm) if trimmed Brass
For general purpose low velocity applications where the most economical flow switch is desired Paddle fits 8 (203mm) minimum duct size Two electrical
McDonnell & Miller
For general purpose low velocity applications where the most economical flow switch is desired Paddle fits 8 (203mm) minimum duct size Two electrical
1 1 4 NPT Brass with sealed tube construction Single pole, double throw snap switch Magnetic switching mechanism eliminates need for
McDonnell & Miller
1 1 4 NPT Brass with sealed tube construction Single pole, double throw snap switch Magnetic switching mechanism eliminates need for
1 NPT Two electrical knock-outs allows connection from either end Sensitivity adjusting screw makes flow adjustment easy Single pole, double throw snap
McDonnell & Miller
1 NPT Two electrical knock-outs allows connection from either end Sensitivity adjusting screw makes flow adjustment easy Single pole, double throw snap

Customer reviews

No reviews yet — be the first

Questions & answers

No questions yet — ask us the first