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SYSTEM SENSOR Duct Smoke Detector: 120V AC/24V AC/DC Volt, Sound Alert, Duct Mount - Smoke Detectors for Fire Alarm Systems
SYSTEM SENSORSmoke Detectors for Fire Alarm Systems

SYSTEM SENSOR Duct Smoke Detector: 120V AC/24V AC/DC Volt, Sound Alert, Duct Mount

The SYSTEM SENSOR D4120 is a duct-mount smoke detector for fire alarm systems, featuring a photoelectric sensor and sound alert. It operates on 24V AC/DC or 120V AC with a current rating of 25 mA @ 24V DC, is…

SKU 3G-OTH-546835

Brand
SYSTEM SENSOR
Item
Duct Smoke Detector: 120V AC/24V AC/DC Volt, Sound Alert, Duct Mount
Category
Smoke Detectors for Fire Alarm Systems
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Technical Specifications

SYSTEM SENSOR
Manufacturer Part Number
D4120
Type
Sound Alert, Duct Mount
Shape
Rectangular
Detects
Smoke
Standards
FM
Alert Type
Sound
Overall Ht
5 in
Sensor Type
Photoelectric
Power Source
Hardwired
Current Rating
25 mA @ 24V DC
Voltage Rating
24V AC/DC
Mounting Location
Duct
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SYSTEM SENSOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SYSTEM SENSOR D4120 is a duct-mount smoke detector for fire alarm systems, featuring a photoelectric sensor and sound alert. It operates on 24V AC/DC or 120V AC with a current rating of 25 mA @ 24V DC, is FM-approved, and has a 5-inch overall height. 3G Electric interprets your demand for this hardwired, rectangular detector and delivers it with specialist support across 14 industrial departments.

Frequently Asked Questions

What is the SYSTEM SENSOR D4120 duct smoke detector used for?

The SYSTEM SENSOR D4120 is a duct-mount smoke detector designed for fire alarm systems in commercial HVAC applications. It uses a photoelectric sensor to detect smoke in air ducts and provides a sound alert, helping to prevent smoke recirculation through ventilation systems.

What are the specifications of the SYSTEM SENSOR D4120?

The D4120 operates on 24V AC/DC or 120V AC with a current rating of 25 mA @ 24V DC. It is FM-approved, hardwired, and has a rectangular shape with a 5-inch overall height. The sensor type is photoelectric, and it mounts directly in the duct.

Where to buy the SYSTEM SENSOR D4120 worldwide?

3G Electric supplies the SYSTEM SENSOR D4120 duct smoke detector worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your facility. Contact us to source this FM-approved detector for your fire alarm system.

How to install the SYSTEM SENSOR D4120 duct smoke detector?

Install the D4120 in the duct with the airflow arrow pointing downstream. Wire per the manufacturer's diagram for 24V AC/DC or 120V AC. Ensure proper clearance for the 5-inch height and test the sound alert after installation. Always follow local fire codes and the SYSTEM SENSOR manual.

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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SYSTEM SENSOR Duct Smoke Detector: 20V AC/24V AC/24V DC Volt, 100 mA Current, Duct Mount, White (MPN D4120W). Key specifications — Current Rating: 100 mA; Body Color: White; Standards: UL; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Power Source: Hardwired; Sensor Type: Photoelectric.
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SYSTEM SENSOR Duct Smoke Detector: 20V AC/24V AC/24V DC Volt, 100 mA Current, Duct Mount, White (MPN D4120W). Key specifications — Current Rating: 100 mA; Body Color: White; Standards: UL; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Power Source: Hardwired; Sensor Type: Photoelectric.
SYSTEM SENSOR Duct Smoke Detector: 120V AC/24V AC/DC Volt, 65 mA @ 24V DC Current, Duct Mount (MPN DUCTSD). Key specifications — Current Rating: 65 mA @ 24V DC; Standards: FM; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Shape: Rectangular; Power Source: Removable Battery; Sensor Type: Photoelectric.
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SYSTEM SENSOR Duct Smoke Detector: 120V AC/24V AC/DC Volt, 65 mA @ 24V DC Current, Duct Mount (MPN DUCTSD). Key specifications — Current Rating: 65 mA @ 24V DC; Standards: FM; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Shape: Rectangular; Power Source: Removable Battery; Sensor Type: Photoelectric.
SYSTEM SENSOR Duct Smoke Detector: 120V/24V Volt, 65 mA Current, Sound Alert, Duct Mount, Round (MPN 2D51). Key specifications — Current Rating: 65 mA; Standards: UL; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Shape: Round; Alert Type: Sound; Power Source: Hardwired.
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SYSTEM SENSOR Duct Smoke Detector: 120V/24V Volt, 65 mA Current, Sound Alert, Duct Mount, Round (MPN 2D51). Key specifications — Current Rating: 65 mA; Standards: UL; Brand: SYSTEM SENSOR; Mounting Location: Duct; Detects: Smoke; Shape: Round; Alert Type: Sound; Power Source: Hardwired.