SYSTEM SENSOR Duct Smoke Detector: 20V AC/24V AC/24V DC Volt, 100 mA Current, Duct Mount
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
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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.
Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.
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.




