System Sensor D4120 System Sensor 4-wire Low Flow Smoke Detector Photo

Brand: System Sensor
SKU: D4120
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In Stock! Ships in 24 hours
Availability: 238

System Sensor 4-wire low flow smoke detector photo electric type


  • 4-Wire Photoelectric, integrated low-flow technology
  • Air velocity rating from 100 ft/min to 4,000 ft/min
  • (0.5 m/s to 20.32 m/sec)
  • Versatile mounting options: square or rectangular configuration
  • Plug-in sensor offers superb false alarm immunity and the latest sensor technology
  • Broad ranges for operating temperature (–4°F to 158°F) and
  • humidity (0% to 95% non-condensing)
  • Patented sampling tube installs from front or back of the detector with no tools required
  • Increased wiring space with a newly added ¾-inch conduit knockout
  • One easy-access Test/Reset button and improved LED status
  • Patented interconnect feature for multi-fan shutdown
  • New high contrast terminal designations
  • Built-in short circuit protection from operator wiring errors
  • Field selectable settings for configuring the detector
  • Two DPDT Form-C relay contacts
  • 24 VAC/DC or 120 VAC
  • Backward compatibility with existing Innovair products, including remote accessories

System Sensor 4-wire low flow smoke detector photo electric type

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.

Product Family

Model NumberDecriptionManufacturerPriceAvail. Qty 
D4120 System Sensor 4-wire Low Flow Smoke Detector Photo System Sensor $139.89 238    Add To Cart

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