The SharpEye 20-20 U & 20-20 UB flame detectors offer
improved ultra violet (UV) optical sensors created from
Spectrex’s continued commitment to R & D. This stateof-
the-art design combines industry performance
requirements and up-to-date electronic microprocessor
technology. The UV sensor band pass has been carefully
selected to ensure the greatest degree of spectral
matching to the radiant energy emissions of fire. Flame
is detected typically within 3 sec. for a 1 sq. ft. pan
gasoline fire. A unique fast UV flame detector model
(20-20 FU) detects within several milliseconds a saturated
UV signal caused by an explosion or a large fire.
The microprocessor design allows for unique field
programmability by easy dip switch and makes these
flame detectors easily adaptable to all environments,
applications & requirements. Multiple detection levels
allow for pre-alarm & alarm response. Both detectors
now offer programmable time delay of up to 30
The SharpEye UV flame detector incorporates a special
logic circuit that helps prevent false alarms caused by
solar radiation. The UV sensor is sensitive to
radiation over the range of
0.185-0.260 microns. This combination of sensor
& Spectrex’s detection logic will sense, analyze &
distinguish between a fire event & a false alarm
stimulus. It is important to note that this
detector must not be exposed to UV radiation
sources such as: electrical arcs, sparks & welding
• UV Spectrum design
• Explosion proof
• Typical 3-second response
• 4-20mA output (source)
• Multiple detection levels - pre-alarm & alarm
• 90°/90° cone of vision
• Standard 4-wire connection
• Adjustable time delay
• MTBF minimum 100,000 hours
• FM, CENELEC/ATEX approved options
• Unitized - no separate controller required
Dimensions: 120 x 132 x 132 mm
Weight: Aluminium 3.7Kg
Base 1.7 Kg
Spectral response: UV: 0.185 - 0.260 microns
Detection range: 1 sq. ft. gasoline fire @ 50 ft.
1 sq. ft. diesel oil fire @ 37 ft.
1 sq. ft. alcohol fire @ 37 ft.
1 sq. ft. n-heptane fire @ 50 ft.
Response time: Typical 3 seconds for a 1 sq. ft. gasoline fire.
Time delay: Adjustable time delay up to 30 seconds.
Field of view: 90° horizontal, 90° vertical.
Temperature range: Operating: -40°F to 160°F
Storage: -65°F to 185°F
Humidity: Relative humiditiy of upto 95% for the operational temperature
Operating voltage: 18-32 Vdc
Power consumption: Max. 80 mA in standby
Max. 120 mA in alarm
Standard two ¾” 14 NPT cable entries.
Optional two M25 x 1.5 cable entries.
Electrical input protection:
Complete electrical interface protection against reversed polarity voltages, surges and spikes according to MIL-STD-1275.
The detector is designed and approved according to the following EMC requirements:
Electrostatic discharge: IEC801-2:1984
Conducted emission: EN55022 Class A
Radiated emission : EN55022 Class A
Radiated immunity: IEC801-3:1984
Dry contact relays:
Alarm: 2 Amps @ 30 Vdc
0.5 Amps @ 250 Vac
Accessory: 5 Amps @ 30 Vdc & 250 Vac
Fault: 5 Amps @ 30 Vdc & 250 Vac
* 4-20 mA current output:
The 4-20mA is source.
Fault: 0 ± 0.5 mA
Normal: 4 mA ± 5%
Warning: 16 mA ± 5%
Alarm: 20 mA ± 5%
Resistance loop: 100 - 600 Ohms