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Mcdonnell & Miller Series AFE-1 Air Flow Switches
Mcdonnell & MillerFlow Switches

Mcdonnell & Miller Series AFE-1 Air Flow Switches

Note: listed by manufacturer as obsolete/discontinued.

SKU 3G-OTH-02751

Also listed as: AFE1 · AFE 1

Brand
Mcdonnell & Miller
Item
Series AFE-1 Air 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-02751 flow switch used for?

The McDonnell & Miller 3G-OTH-02751 flow switch is designed for industrial hazardous environments requiring NEMA 7 (Class I, Division I, Groups C and D) or NEMA 9 (Class II, Division I, Groups E, F, and G) enclosures. It detects liquid flow in piping systems to trigger alarms or control equipment in explosive atmospheres.

What are the specifications of the McDonnell & Miller 3G-OTH-02751?

The McDonnell & Miller 3G-OTH-02751 is a flow switch for hazardous locations. It features a NEMA 7 or NEMA 9 enclosure suitable for Class I, Division I, Groups C and D, and Class II, Division I, Groups E, F, and G. The manufacturer lists this model as obsolete or discontinued.

Where to buy the McDonnell & Miller 3G-OTH-02751 in Singapore?

3G Electric supplies the McDonnell & Miller 3G-OTH-02751 flow switch to Singapore. We source and deliver this obsolete model, handling logistics and customs clearance for your facility. Contact us for availability and lead time on this discontinued hazardous-location flow switch.

How to select a replacement for the McDonnell & Miller 3G-OTH-02751?

When selecting a replacement for the McDonnell & Miller 3G-OTH-02751, verify the required hazardous-location classification (NEMA 7 or NEMA 9) and pipe size. Since the 3G-OTH-02751 is discontinued, consult a qualified engineer to choose a current model with equivalent flow range and enclosure rating. 3G Electric can help source suitable alternatives.

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
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Paddle-type flow switch for liquids, with brass body and 1 1/4 in NPT connection. SPDT contacts rated 7.4 A at 120 V full load. For pipe sizes from 1 1/4 in to 16 in. Suitable for hazardous locations Class II, Div 1 and 2, Groups E, F, G
McDonnell & Miller
Paddle-type flow switch for liquids, with brass body and 1 1/4 in NPT connection. SPDT contacts rated 7.4 A at 120 V full load. For pipe sizes from 1 1/4 in to 16 in. Suitable for hazardous locations Class II, Div 1 and 2, Groups E, F, G

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