Duct Smoke Detector Model no : D4120

Smoke introduced into an air duct system will be distributed throughout the entire building. Smoke detectors designed for use in air duct systems are used to sense the presence of smoke in the duct. Model D4120 and D4S Duct Smoke Detectors utilize 4-wire photoelectric technology for the detection of smoke. This detection method, when combined with an efficient housing, samples air passing through the duct allowing detection of a developing hazardous condition. When sufficient smoke is sensed, an alarm signal is initiated and appropriate action can be taken to shut off fans, blowers, change over air handling systems, etc. These actions can facilitate the management of toxic smoke and fire gases throughout the areas served by the duct system. The D4120 and D4P120 detectors are designed to operate on 24 VDC/VAC or 120 VAC. Alarm and supervisory relay contacts are available for control panel
interface (alarm initiation), HVAC control, and other auxiliary functions. Auxiliary relays are provided for fan shut down. Detector interconnection provides signaling of up to 50 other detectors in the loop for multiple fan shut down.
These detectors are not designed for 2-wire applications.