Detector sensitivity – Det-Tronics C7050 A, C, G, P UV Flame Detector User Manual
Page 9

DETECTOR SENSITIVITY
The UV flame detector responds to radiation over wave-
lengths of 185 to 245 nanometers (1850 to 2450
angstroms). Figure 6 illustrates the range of sensitivity,
and compares this range to other forms of radiation.
Note that UV radiation reaching the earth from the sun
does not extend into the region of sensitivity of the detec-
tor. In addition, radiation from normal artificial lighting,
such as fluorescent, mercury vapor, and incandescent
lamps does not extend into the detector’s spectral range.
As a result, the detector is insensitive to these forms of
radiation and may be used outdoors or indoors.
NOTE
Some mercury vapor lamps can operate for extend-
ed periods with cracked or otherwise damaged
envelopes, and will then emit UV radiation in the
frequency response range of the detector.
Defective mercury vapor lamps should be immedi-
ately removed from service.
The UV sensor responds to any radiation that can penetrate
its glass envelope and create ion pairs. The glass enve-
lope absorbs most alpha or beta particles, but it permits
both gamma and x-rays to pass through. If these rays cre-
ate ion pairs between the electrodes near the cathode, the
normal discharge process will occur and the detector will
(A)
(B)
(C)
1.48 (37.59)
(D)
B1475
ALL CONTROLLER CAGES REQUIRE
A MINIMUM OF 10.12 INCHES (257.1 MM)
DEPTH CLEARANCE
(E)
Figure 5—Q4004 Mounting Cage Dimensions in Inches (Millimeters)
7
95-8242
PART NUMBER
CONTROLLER
005269-XXX
POSITIONS FOR:
HT:
DIM. (A)
DIM. (B)
DIM. (C)
DIM. (D)
DIM. (E)
WEIGHT
FIRE GAS
INCH MM
INCH MM
INCH MM
INCH MM
INCH MM
LB
KG
–001
8
16
4U
19.00
482.6
18.30
464.8
17.36
440.9
4.00
101.6
6.97
177.1
9.3
4.2
–002
6
12
4U
15.06
382.6
14.36
364.7
13.42
340.9
7.6
3.5
–003
4
8
4U
11.13
282.6
10.43
264.9
9.49
241.1
5.9
2.7
–004
3
6
4U
9.16
232.7
8.46
214.9
7.52
191.0
5.1
2.3
–005
2
4
4U
7.19
182.7
6.49
164.9
5.55
141.0
4.2
1.9
–006
1
2
4U
5.22
132.6
4.52
114.8
3.58
90.9
3.1
1.4
5.0
4.0
3.0
2.0
1.5
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
ATMOSPHERIC
TRANSMISSION
WAVELENGTH (MICRONS)
SOLAR RADIATION REACHING THE EARTH
VISIBLE
INFRARED
ULTRAVIOLET SENSOR RESPONSE
ULTRAVIOLET
100
75
50
25
0
A1898
Figure 6—Detector Range of Sensitivity