Dräger Flame 5000, Техническое руководство

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Installation of the Dräger Flame Detector 5000
Exposure to Flare Radiation
Flame detectors are frequently used where hydrocarbon fi re hazards are expected; these are quite often processing
plants where a fl are stack is in use nearby. The detector should not have a direct view of the fl are.
Flexibility of mounting location
The detector requires a clear unobstructed view of the potential hazard. In order to avoid local obstructions, such
as pipe-work and cable trays, a 2m helix should be provided in the detector cable to allow local repositioning of the
detector.
Mounting Arrangements
Firm, vibration free mountings are essential for the operation of optical systems and the detector should, wherever
possible, be
fi xed to rigid mountings.
Thermal Disruption
Thermal convection plumes and exhaust gas plumes generally exhibit a visual ‘mirage’ e ff ect. In most cases this does
not a ff ect detector operation or sensitivity. The detector does not respond to black body radiation near the exhaust.
Optical Contamination
There are many sources of contamination such as oil, water (deluge water, rain and sea-spray), snow, ice, and internal
misting. The design of the detector incorporates an internal heater in order to resist condensation and ice build-up.
Excessive contamination of the detector faceplate may result in an increased maintenance requirement and potentially
reduce the detector’s sensitivity.
Where detectors are mounted at low level, care should be taken to avoid contamination (such as water and oil) from
equipment above the detector. Care should be taken in sighting the detector to minimise the likelihood of such
contamination.
Fog, smoke and other similar airborne contaminants a ff ect the detector’s sensitivity by reducing the detector’s range.
Enclosed Areas
In enclosed areas, if dense smoke is expected to accumulate at the onset of the fi re, the detectors should be mounted
1-2m below the ceiling level.
The mounting bracket
The detector mounting bracket is designed to allow the detector to be mounted from a horizontal plane. The bracket
supplied with the detector and the dimensions of the
fi xing holes are illustrated on the following page.