AT-FD201 Ultraviolet Flame Detector with Relay Output

Product Description

The AT-FD201 UV Flame Detector is an intelligent, relay-output flame sensor that detects the ultraviolet radiation emitted by open flames. It is designed for high-hazard applications where flammable or explosive liquids and solids are stored, handled or processed. The detector uses a highly sensitive UV photosensitive tube optimized for the 180–290 nm spectral range, allowing rapid response to real flames while maintaining strong immunity to false alarms caused by sunlight, dust, oil mist and humidity.
With a 120° field of view and Grade I sensitivity (25 m detection distance with a 2 kg ethanol fire in a 33 × 33 × 5 cm pan), the AT-FD201 offers wide-area coverage in a compact housing. The detector operates from 12–28 VDC, with low standby current (≤10 mA @ 24 VDC) and alarm current ≤30 mA @ 24 VDC, making it suitable for loop-powered systems and panels with limited current capacity.
The AT-FD201 features a changeover relay output (NO/NC selectable via jumper) and a DIP switch for configurable alarm delay (1 s / 3 s / 6 s / 15 s) to match different site conditions, including areas with smoke or sunlight interference. It can be wired either to a security alarm panel (pure relay mode) or to a conventional fire alarm panel using the built-in 470 Ω resistor, providing flexible integration options.

Key Features

• Ultraviolet-only flame detector for fast flame detection

• UV spectrum: 180–290 nm

• Detection sensitivity: Grade I, 25 m @ standard ethanol test fire

• Wide 120° detection angle (vertical and horizontal)

• 12–28 VDC operating voltage

• Low standby current ≤10 mA @ 24 VDC, alarm current ≤30 mA @ 24 VDC

• NO/NC relay output (1 A @ 24 VDC) configurable by jumper

• Selectable alarm delay: 1 s / 3 s (default) / 6 s / 15 s

• Latching / non-latching alarm mode selectable by DIP switch

• Can be connected to security alarm panels or conventional fire alarm panels (470 Ω loop output)

• LED indication: blinking in normal, steady ON in alarm

• Compact design: Ø103 mm × 45 mm (installed in base), ~153 g

• Operating temperature: -20°C to +55°C

• Operating humidity: 10–93 %RH, non-condensing

• Protection rating: IP21
  
  

  Technical Specifications

  Electrical

  Item	Specification
  Model	AT-FD201
  Operating Voltage Range	12–28 VDC
  Standby Current	≤10 mA @ 24 VDC
  Alarm Current	≤30 mA @ 24 VDC
  Relay Contact Rating	1 A @ 24 VDC
  Output Type	Changeover relay (NO/NC selectable), 470 Ω loop*

  
  
  

  Optical & Detection

  Item	Specification
  Spectrum	180–290 nm (UV)
  Detection Angle	120° (typical)
  Detection Sensitivity	Grade I, 25 m @ 2 kg ethanol fire in 33×33×5 cm pan

  Environmental & Mechanical

  Item	Specification
  Operating Temperature	-20°C to +55°C
  Operating Humidity	10–93 % RH, non-condensing
  Protection Rating	IP21
  Height (installed)	45 mm (with base)
  Diameter	103 mm
  Weight	Approx. 153 g

  
  

  Typical Applications

  • Petrochemical plants and fuel storage areas

  • Paint spray booths and solvent storage rooms

  • Munitions factories and explosive material handling areas

  • Engine rooms and generator rooms

  • Industrial process lines with open flames or burners

  • High-risk indoor spaces where fast flame detection is required