Dräger Flame 5000, Техническое руководство

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Installation of the Dräger Flame Detector 5000
Installation of the Dräger Flame Detector 5000
In considering the application of the Dräger Flame Detector 5000 it is important to know of any conditions that may
prevent the detector from responding. The detector provides reliable response to visible
fl ames within its fi eld of view,
and insensitivity to common false alarm sources.
Solid obstructions or a direct view of intense light sources may interfere with the detector sensitivity. Sca ff olding or
tarpaulins in the detector’s fi eld of view may reduce coverage. Contamination of the detector window may result in a
reduction in sensitivity.
The detector provides a live colour video image for surveillance of the protected area. As with conventional video
cameras the detector should not face directly towards the sun or a brightly lit scene. In such conditions the detector’s
automatic exposure control would darken the image in order to avoid overexposure; the resulting picture may be too
dark for surveillance purposes. To obtain the best possible picture the detector should be facing away from the sun.
In the case of an o
ff shore vessel or platform, the detector should ideally be placed facing inwards towards the plant
and with minimal view of the horizon.
The detector has a horizontal fi eld of view of 90° and a vertical fi eld of view of 65°. The location and orientation of the
detector in relation to the protected area determines the actual footprint. Achieving the desired coverage depends on
congestion within the protected space, the location of the detector(s) and the distance of the detector from the hazard.
It may be necessary to install more than one detector within an area in order to achieve adequate coverage.
The detector sensitivity, expressed as fi re size at a distance, is determined visually by the apparent size of the fi re. This
is a function of the fuel source, how it is released and distance from the detector to the fi re. The detector response
time is relatively independent of fuel type and/or distance.
In common with other forms of fl ame detection, the detector’s sensitivity is reduced and potentially blinded by dense
obscurants such as smoke, fog and other airborne particulates. The detector is insensitive to arc welding, however
should not be conducted within 1m of the detector.
Mechanical Install.
Detector Enclosure
The Draeger Flame Detector 5000’s electronics are housed in an enclosure certi fi ed for use in a hazardous areas. The
enclosure comprises of:
Front enclosure cover (including the faceplate window) •
Rear enclosure cover. •
Enclosure body (with certi fi cation label). •
Mounting bracket. •
The mounting bracket allows the detector’s vertical orientation to be adjusted from 0-45°, and allows a horizontal
rotation of ±45 °.