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System Sensor D4120 - Duct Smoke Detector - Photoelectric 4-Wire

Item: D4120
MFR: D4120
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The Innovair Flex D4120 Duct Smoke Detectors provide superb immunity to false alarms and easy, labor saving installation options. Its flexible configurations allow an easy replacement to any model, and its 2 to 1 sensor to power board offers cost savings where both supply and return installation is required.

The InnovairFlex D4120 4-wire photoelectric duct smoke detector features a pivoting housing that fits both square and rectangular footprints and mounts to round or rectangular ductwork. This unit senses smoke in the most challenging conditions. An improved cover design isolates the sensor head from the low-flow feature for simple maintenance. With its 2:1 sensor-to-power capability, the power board of the D4120 may be used to monitor a second sensor, D4S, simultaneously (i.e., supply and return side). As many as 50 InnovairFlex detectors can be interconnected. When one unit senses smoke, all interconnected detectors will switch their relays; only the detector sensing smoke will go into alarm, thus pinpointing the fire source. An easy-access Test/Reset button makes it possible to test the unit with the cover on. Three DIP switches can be used to configure field selectable settings: cover tamper delay, number of sensors to be controlled, and shut down on trouble option. Each power board has two LEDs that can be used to indicate the status of connected sensors, and a quick reference imprinted on the cover explains the LED status indications (Standby, Maintenance, Trouble, and Alarm). The InnovairFlex duct smoke detector can be customized to meet local codes and specifications without additional wiring.
  • Versatile mounting options: square or rectangular configuration
  • Air velocity rating from 100 ft./min to 4,000 ft./min (0.5 m/s to 20.32 m/sec)
  • 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
  • Plug-in sensor offers superb false alarm immunity and the latest sensor technology
  • Increased wiring space with a newly added 3/4" 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, 24 VDC or 120 VAC
  • Backward compatibility with existing Innovair products, including remote accessories


NameSystem Sensor D4120 - Duct Smoke Detector - Photoelectric 4-Wire
Gemaire Item NumberD4120
Manufacturer Product NumberD4120
SKU - PIM Number1364408732813
ERP Number242432
Unit of MeasureEA
Weight3.3 Pounds (Lb)
Length14.4 Inches (In)
Width5.0 Inches (In)
Height2.5 Inches (In)
Country of OriginMEX
BrandSystem Sensor
Voltage120 VAC
Power SourceDC
Cycle/Hertz50/60 Hz
Batteries IncludedNo
Hush ButtonNo
Test ButtonYes
Audible AlertNo
Battery BackupNo
Batteries RequiredNo
Detection MethodPhotoelectric
Sensor TypePhotoelectric
ApplicationDuct Smoke Detection
Interconnection Capability50
Locking PinNo
MountingSide by Side or Top over Bottom
Operating Temperature Range-4°F to 158°F (-20°C to 70°C)
TypeDuct Smoke Detector
Visual AlertNo
Warranty OfferedYes
CUL ListedNo
UL ListedYes
UL RecognizedNo
Terminal ConnectionYes
Operating Temperature-4°F to 158°F (-20°C to 70°C)
StandardsUL, FM, CSFM
Contact RatingAlarm initiation contacts (SPST) 2.0A @ 30 VDC (resistive)Alarm auxiliary contatcs (DPDT) 10A @30 VDC (resistive)10A @250 VAC (resistive)1/2 HP @240 VAC1/4 HP @120 VACNOTE: Alarm auxiliary contacts shall not be connected to initiating circuits ofcontrol panels. Use the alarm initiation contact for this purpose.Supervisory Contacts (SPDT) 2.0A @ 30 VDC (resistive)2.0A @ 125 VAC (resistive)
Maximum Voltage120 VAC/24 VDC
ApprovalsUL, ULC, FM, CSFM
Wire GaugeUp to 12 AWG
Switch ActionDip Switches
Connection TypeTerminal Block
GEM - Case Quantity


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