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Det-Tronics X2200 UV Flame Detector with Pulse Output User Manual

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95-8552

5.3

4

gENERal aPPlICaTION

INfORmaTION

RESpONSE ChARACTERISTICS
Response is dependent on distance, type of fuel,

temperature of the fuel, and time required for the fire to

come to equilibrium. As with all fire tests, results must

be interpreted according to an individual application.

See Appendix A for fire test results.

wELDING
Electric arc welding is a source of intense ultraviolet

radiation. UV radiation from arc welding readily scatters

and can deflect across significant distances, even when

direct obstructions exist. Any open door or window can

allow nuisance UV radiation from arc welding to enter an

enclosed area.

It is recommended that the system be bypassed during

welding operations in situations where the possibility of a

false alarm cannot be tolerated. Gas welding mandates

system bypass, since the gas torch is an actual fire.

ARTIFICIAL LIGhTING
The X2200 should not be located within 3 feet of artificial

lights. Excess heating of the detector could occur due to

heat radiating from the lights.

EMI/RFI INTERFERENCE
The X2200 is resistant to interference by EMI and RFI,

and is EMC Directive compliant and CE Marked. It will

not respond to a 5 watt walkie-talkie at distances greater

than 1 foot.

FALSE ALARM SOURCES
The UV sensor is solar blind to the ultraviolet component

of solar radiation. However, it will respond to sources of

UV besides fire, such as electric arc welding, lightning,

high voltage corona, x-rays and gamma radiation.

FACTORS INhIBITING DETECTOR RESpONSE
windows
Glass and Plexiglas windows significantly attenuate UV

radiation and must not be located between the detector

and a potential flame source. If the window cannot be

eliminated or the detector location changed, contact

Detector Electronics for recommendations regarding

window materials that will not attenuate UV radiation.

Obstructions
Radiation must be able to reach the detector in order

for it to respond. Care must be taken to keep physical

obstructions out of the line of view of the detector. In

addition, UV absorbing gases or vapors must not

be allowed to accumulate between the detector and

the protected hazard. See Table 2 for a list of these

substances.

Smoke
Smoke will absorb UV radiation. If accumulations

of dense smoke can be expected to precede the

presence of a flame, then detectors that are used

in enclosed areas should be mounted on the wall

approximately 3 feet (1 meter) from the ceiling where

the accumulation of smoke is reduced.

Detector viewing windows
It is important to keep the detector viewing windows as

free of contaminants as possible in order to maintain

maximum sensitivity. Commonly encountered substances

that can significantly attenuate UV radiation include, but

are certainly not limited to, the following:
Silicones

Oils and greases

Dust and dirt buildup

Paint overspray