Flame Detection Theory
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Transcript Flame Detection Theory
Flame
Detection
Theory
EVERY LIFE HAS A PURPOSE…
Requirements of a Fire
Oxygen
Characteristics of a Fire
High Emissions of Ultraviolet Radiation
High Emissions of Infrared Radiation
Presence of Light, Smoke and Airborne Debris
False Alarm Sources
Arc Welding
Sunlight
Infrared Energy
Modulation
Reflective
Characteristics of a Fire
Ultraviolet Region
Visible Region
Infrared Region
Relative
Energy
Wavelength
2 to 3
microns
400nm
Sun’s radiation
reaching the Earth
UV Phototube
Ultraviolet Region
Visible Region
Infrared Region
Relative
Energy
2 to 3
microns
400nm
Sun’s radiation
reaching the Earth
UV Phototube
Ultraviolet
Radiation
Anode
Photocathode
Electrons
Gas-Filled
Phototube
VDC
+
IR Devices
Visible Region
Ultraviolet Region
Infrared Region
Relative
Energy
400nm
2 to 3
microns
Sun’s radiation
reaching the Earth
Wavelength
IR Devices
Ultraviolet Region
Visible Region
Infrared Region
Hydrogen fires
emit H2O vapors
@ 2.95 microns
Relative
Energy
Wavelength
2.7 to 3 .2
microns
400nm
Sun’s radiation
reaching the Earth
FlameGard 5 UV/IR
FlameGard 5 UV/IR
Ultraviolet + Infrared Detection
Photo-tube + Pyroelectric (Flicker)
FlameGard 5 UV/IR Features
Monitors in both UV and IR spectral ranges
reducing possibility of false alarms caused by
lightning, arc welding, hot objects etc.
Typical Response time: < 3 seconds @ 50ft
120° maximum horizontal field of view
-40°F to +185°F (-40°C to +85°C) operating
temperature
COPM (Continuous Optical Path Monitoring)
RS-485 Modbus RTU, HART
Hydrogen fire configuration available
FlameGard 5 UV/IR
Physical Characteristics
Assembly
Three Distinct Explosion-proof Housings:
UV/IR
COPM Light Rods (Reflective Coated)
UV - Straight
IR - Curved
O-Ring Sealed Windows
Common Base with Bracket Mounting Holes
Two (2) Bottom Entry Conduit Connections (3/4” NPT)
“Drip Lip” (3/4 of housing mating surface)
FlameGard 5 UV/IR Specifications
Environmental
Temperature
FlameGard 5 UV/IR
-40°C to 85°C (-40°F to 185°F)
Ratings
IP 66, Type 4X, Class I, Div 1, Groups B, C & D;
Class II, Groups E, F & G; Class III
FlameGard 5 UV/IR Specifications
Performance
Improved detection and false alarm immunity
Field-of-View
FlameGard 5 UV/IR - 115° Vertical, 120° Horizontal
Optical Sensitivity
1 sq. ft. fire at 50 ft.
FlameGard 5 UV/IR Field of View
(Horizontal)
0°
15°
15°
50'
30°
30°
45'
40'
45°
75%
45°
35'
30'
60°
100%
60°
25'
20'
15'
10'
50%
TABLE CHART
(±5°)
HORIZONTAL
HORIZONTAL
SENSITIVITY
100%
75%
50%
100%
75%
50%
0°
50'
50'
25'
±15°
50'
50'
15'
±30°
50'
50'
<5'
±45°
50'
30'
<5'
±60°
25'
<20'
<5'
+60°
+45°
SENSITIVITY
TABLE CHART
100%
100%
+30°
VERTICAL
75%
100%
75%
50%
TABLE CHART
(±5°)
HORIZONTAL
HORIZONTAL
SENSITIVITY
100%
75%
50%
0°
100%
75%
50%
50'
50'
25'
FlameGard 5 UV/IR Field of View
(Vertical)
±15°
50'
50'
15'
±30°
50'
50'
<5'
±45°
50'
30'
<5'
±60°
25'
<20'
<5'
+60°
SENSITIVITY
+45°
TABLE CHART
100%
100%
+30°
VERTICAL
100%
75%
50%
0°
50'
50'
25'
±15°
50'
50'
25'
±30°
50'
50'
25'
±45°
50'
30'
<20'
±60°
20'
<20'
<20'
75%
50%
50%
-15°
-30°
-45°
-60°
10'
15'
20'
25'
30'
35'
40'
0°
45'
+15°
50'
75%
(±5°)
VERTICAL
FlameGard 5 UV/IR Specifications
Performance
Spectral Sensitivity
FlameGard 5 UV/IR:
185 to 260 nanometers & 4.35 microns
Response Time (Normal Operation
FlameGard 5 UV/IR
Detector Response (nominal)
< 500ms
Output Response (50 ft. fire)
< 3sec.
FlameGard 5 UV/IR Specifications
Outputs
4-20 mA Signal
0 mA, Fault
2 mA, COPM Fault
4 mA, Ready
8 mA, IR Only
12 mA, UV Only
16 mA, Warn
20 mA, Alarm (After time delay)
FlameGard 5 UV/IR Specifications
Outputs
Commands
Read Only
4-20 mA
Alarm, Warning, Fault
UV Only Signal, IR Only Signal
UV Source Lamp Fault, IR Source Lamp Fault
Low Voltage
Communication Faults
Write Only
Auto Test, Reset, Accept
Read and Write
Address, Modbus Setup
Sensitivity (100%, 75%, 50%)
Time Delay, Relay States
FlameGard 5 UV/IR Specifications
Outputs
Relays: (3) SPDT (8-amp, 24 VDC/250 VAC
Resistive)
Warning (Immediate, no time delay)
Alarm (After 2, 4, 8 or 10 Sec. Time Delay)
Dip Switch Selectable
RS-485 Selectable (Non-intrusive over-ride)
Fault (Energized, non-latching )
FlameGard 5 UV/IR Specifications
System
Modes:
Normal
Self Test (Power-up)
Alarm Test (Remote)
Fault Diagnostic -Status Indication (LED)
RED LED
GREEN LED
ALTERNATING
OFF
CONDITION
TIME OUT – 10 SECONDS AFTER START-UP
10 SEC. BLINK
READY – NO FLAME RADIATION PRESENT
SLOW BLINK
ON
WARN – FLAME RADIATION PRESENT
FAST BLINK
ON
ALARM – WARN +TIME DELAY
OFF
SLOW BLINK
FAULT –COPM FAULT DETECTED
OFF
FAST BLINK
FAULT – LOW VOLTAGE CONDITION
Other Fault Diagnostics via RS-485
FlameGard 5 UV/IR Specifications
Approvals
CSA, FM, ATEX, CE Marking
Power
20-36 VDC Nominal @ 150 mA Max.
Input Terminals
Test and Reset
Wiring: 12 AWG to 22 AWG
FlameGard 5 Test Lamp
Rechargeable/replaceable
batteries
Easy grip handle integral
with housing
Spring return on/off
switch to conserve
battery life
Explosion-proof cast
aluminum housing
CSA Approved
ATEX Approved
Key Features / Benefits
Excellent Discrimination of False Alarms
UV detection in the 185-260 nanometer range which
is well below natural sunlight and artificial light.
IR detection at 4.3 microns which is the CO2 spike
generated from hydrocarbon fires.
Flicker discrimination algorithm, which eliminates
false alarms from IR sources.
Arc welding and lightning will not cause the
FlameGard UV/IR to go to false alarm.
Key Features / Benefits
“COPM” Continuous Optical Path Monitoring
We check the optical path once every minute on both
the UV and IR sides to make sure the windows are
not dirty, and that the test sources and detectors are
working properly.
Wide Angle of View
120° angle of view is the widest in the industry which
allows for a larger area of coverage and a reduced
number of detectors.
Key Features / Benefits
Hydrogen Fire Specific Flame Detector
Uses a wavelength of 2.7-3.2 microns on
the IR detector to detect the water spike of
Hydrogen fires.
Output Capability
Three programmable relays (8 AMP)
0-20 mA stepped output to allow quick
diagnostics for UV only, IR only, COPM
Fault and overall Failures
Modbus for digital communication
HART------Digital Communication protocol.
Communicates via analog output line.