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SYSTEM SENSOR D4120W Duct Smoke Detector, Photoelectric, 24V DC, 100 mA, White - Smoke Detectors for Fire Alarm Systems
SYSTEM SENSORSmoke Detectors for Fire Alarm Systems

SYSTEM SENSOR D4120W Duct Smoke Detector, Photoelectric, 24V DC, 100 mA, White

The SYSTEM SENSOR D4120W is a UL-listed duct smoke detector with a photoelectric sensor, hardwired for 20V AC/24V AC/24V DC power and rated at 100 mA current. Designed for duct mounting in fire alarm systems, it…

SKU 3G-OTH-546837

Brand
SYSTEM SENSOR
Item
D4120W Duct Smoke Detector, Photoelectric, 24V DC, 100 mA, White
Category
Smoke Detectors for Fire Alarm Systems
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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 Specifications

SYSTEM SENSOR
Manufacturer Part Number
D4120W
Type
100 mA Current, Duct Mount, White
Detects
Smoke
Standards
UL
Body Color
White
Sensor Type
Photoelectric
Power Source
Hardwired
Current Rating
100 mA
Voltage Rating
24V DC
Mounting Location
Duct

Technical Documents

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SYSTEM SENSOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SYSTEM SENSOR D4120W is a UL-listed duct smoke detector with a photoelectric sensor, hardwired for 20V AC/24V AC/24V DC power and rated at 100 mA current. Designed for duct mounting in fire alarm systems, it features a white body and is part of our broad industrial safety portfolio across 14 departments, with specialist depth in combustion, pumps, and controls.

Frequently Asked Questions

What is the SYSTEM SENSOR D4120W duct smoke detector used for?

The SYSTEM SENSOR D4120W is a UL-listed photoelectric duct smoke detector used in HVAC systems to detect smoke in air ducts. It triggers fire alarm systems to prevent smoke circulation, protecting building occupants and equipment. 3G Electric supplies this detector as part of our industrial safety portfolio.

What are the specifications of the SYSTEM SENSOR D4120W?

The D4120W operates on 20V AC/24V AC/24V DC with a 100 mA current rating. It features a photoelectric sensor, hardwired power, white body, and duct mounting. It is UL-listed and detects smoke for fire alarm systems. 3G Electric sources this SYSTEM SENSOR model globally.

Where to buy the SYSTEM SENSOR D4120W worldwide?

3G Electric supplies the SYSTEM SENSOR D4120W duct smoke detector worldwide. We handle full logistics, customs clearance, and delivery to your site. As a global industrial solutions provider, we source genuine SYSTEM SENSOR parts and support your procurement needs across 14 departments.

How to install the SYSTEM SENSOR D4120W duct smoke detector?

Install the D4120W in the air duct per NFPA 72 and local codes. Mount it securely, wire to 20V AC/24V AC/24V DC power, and connect to the fire alarm panel. Test per manufacturer guidelines. 3G Electric provides sourcing support for this SYSTEM SENSOR detector and related controls.

SYSTEM SENSOR Products

3G Electric supplies SYSTEM SENSOR smoke detectors for fire alarm systems. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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