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D381 Flame Detector

UV/3-IR MULTI-SPECTRUM FLAME DETECTOR FOR INDUSTRIAL APPLICATIONS

The Detectors Incorporated Model D381 UV/3-IR Multi -Spectrum Flame Detector is the most advanced optical flame optical flame detector designed to respond to Hydrocarbon, Non-Hydrocarbon, and Hydrogen fires while rejecting False Alarm sources. The D381 detectors sense UV radiation in the Ultraviolet spectrum and Infrared radiation in 3 discrete bands of IR spectrum for detecting fires. Flame response and false source rejection for the D381 models is accomplished by utilizing the Convolution Method and Advanced DSP (Digital Signal Processing) in conjunction with hard coded algorithms identifying specific wavelengths of energy. The detector is able to respond to Hydrocarbon and Non-Hydrocarbon fires at a distance of 80+ feet. All this while rejecting False sources.

The D381 detector is designed for a multitude of applications. The detector will respond to a 1 ft. x 1 ft. n-Heptane or IPA fires from 200 feet within approximately 3-5 seconds. The Model D381 is a high-speed flame detector designed specifically for liquid spray paint and powder coating applications or anywhere a fast detection time is required. The Models D381 series are standalone fire & flame detectors in watertight NEMA 4 (IP66/67) Aluminum enclosure. The detectors feature automatic self-test for continuously checking the optical path integrity while monitoring the electronics to ensure utmost reliable operation and fault reporting.

PRODUCT FEATURES
  • Multi-Spectrum Detection – 3IR + UV design identifies hydrocarbon, non-hydrocarbon, and hydrogen fires with high false alarm immunity.
  • Versatile Outputs – Standard warning, alarm, fault, auxiliary relays, and RS-485 ModBus allow seamless system integration.
  • Event Logging – Stores up to 200 events and 6 FireGraphs® for reliable tracking of fire activity.
  • Adjustable Response Delay – Time/verification delay up to 20 seconds provides precise detection control.
  • Automatic Self-Test – OptiRadar® technology checks electronic circuitry and optical path integrity for dependable operation.
  • Durable Enclosure – Copper-free aluminum with powder-coated finish protects against harsh conditions.
  • Manual Test Mode – Simplifies on-site verification of detector function.
  • Easy Wiring – Screw terminal block allows quick and reliable field connections.
  • Solar Blind Design – Reduces false alarms caused by sunlight exposure.
  • Optional Heater – Prevents condensation and icing for reliable performance in cold environments.
  • 0–20 mA Output Option – Supports enhanced integration with control systems.
  • Made in USA with 5-Year Warranty – Built to high-quality standards for long-term reliability.

General

  • Field-of-View: 90° Horizontal and Vertical
  • Spectral Sensitivity: 180–260 nm (UV); 2–5 µm (IR) 3 discrete bands
  • Detection Range: 12 in × 12 in n-Heptane fire 40 ft (12.2 m) FM;36 in Hydrogen Plume 200 ft (61 m) DI
  • Response Time: Typically 3–5 seconds

Electrical

  • Operating Voltage: 24 VDC nominal (18–31), regulated
  • Standby Power: 60 mA, 24 VDC
  • Alarm Power: 90 mA, 24 VDC
  • Heater Option: 120 mA additional

Mechanical

  • Enclosure: 360 copper-free aluminum, powder coated red
  • Dimensions: 4.53 in × 4.09 in × 2.95 in
    (115 mm × 104 mm × 75 mm)
  • Weight: 2.5 lb (1.1 kg)
  • Mounting: Stainless steel swivel arm
    (order separately #DA-002), 6.6 lb (3 kg)
  • Conduit Entries: Standard (1) M25
  • Wiring: 12–22 AWG (3.3–0.33 mm2)

Environmental

  • Operating Temperature:
    -40°F to +185°F (-40°C to +85°C);
    -55°F to +185°F (-48.3°C to +85°C) with heater option
  • Operating Humidity: 5–95% RH non-condensing
  • Vibration: in compliance with FM 3260-2003, meets or exceeds MIL-STD 810C
  • Enclosure Type: NEMA 4, IP66/IP67

Relay Operations

  • Output Relays: Alarm/Auxiliary/Fault
    SPDT contacts 2 A, 24 VDC; Alarm & Auxiliary Relays de-energized; Fault relay energized.
  • Adjustable Time/Verification Delay:
    Aux Relay 0.3, 3, 10, 20 s
  • Analog Output: 0–20 mA stepped, source
  • Communication: RS-485 Modbus
  • Visual Indications: Green/Normal; Red/Alarm; Amber/Fault

  • Airports & Aircraft Hangars

  • Warehouse & Storage Facilities

  • Manufacturing & Food Processing

  • Diesel Generators & Fuel Storage

  • Battery Rooms & Charging Facilities

  • Compressor Stations

  • Paint & Solvent Storage Facilities

  • Recycling Centers

  • Power Plants

  • Meets or exceeds MIL-STD 810C.
  • In compliance with FM3260-2003
D381 approvals: USA/Canada FM Approved, CE Mark, California State Fire Marshal (CSFM), 3260

  • DA-002: 316 SS Mounting Arm

  • DA-003: Air Purge Kit for D383

  • DA-007: Weather Shield

  • DA-008: Detector Key Test Station

  • DA-010: Non-Isolated 0–20 mA Stepped analog Output

  • DA-011: Heater Pad Option

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