Honeywell Searchline Excel Open-Path Technical Handbook page 16

MAN0530 Issue 09 October 03
2104M0506
3. INSTALLATION AND OPERATION
Below this temperature, snow or ice blown onto the window will not be melted until the ambient
temperature rises. If long-term, outdoor operation in very cold climates is intended, it is
recommended that extra shielding/covers are employed to prevent snow/ice from being blown
onto the windows and building up.
Note: The heated optics have not been evaluated as part of the performance testing relating to
the FM approval and therefore are not considered part of the performance approval.
Deluge and Flooding - Searchline Excel is rated IP66/67 and as such will not be damaged by
occasional deluge or flooding. However, during such instances the unit will completely lose its
IR signal and will enter the BEAM-BLOCK/FAULT state. Also, when the deluge/flooding subsides,
there is the possibility that contaminants will be left on the windows. Therefore, it is recommended
that Excel units be located away from areas particularly prone to deluge or flooding.
Areas Prone to Subsidence and Settling - Where possible, it is recommended that Excel units
are not mounted on structures located where problems with subsidence, settling or thawing of
permafrost are known to cause significant movement. If such locations cannot be avoided, the
foundations of the mounting structure should be engineered to minimise any angular movements.
Areas Prone to Earthquakes - In locations prone to earthquakes, there is a chance that
during or after an earthquake, the units of an Excel gas detector will become misaligned with
respect to each other. Provided that the Excel units do not suffer from direct mechanical impact
damage during an earthquake, they should remain undamaged by such events. Anti-vibration
mounts are unlikely to be of any benefit and are not recommended. After an earthquake it is
recommended that Excel gas detectors are visited and their alignment be checked.
Accidental Impact - Locations where there is a significant likelihood of equipment, personnel
or moving objects accidentally knocking Excel units out of alignment should where possible be
avoided. If such locations cannot be avoided, measures including improved mechanical
protection and warning notices should be considered.
Intense Electromagnetic Fields - Searchline Excel complies with EN50082 (Industrial levels)
and as such is well protected from interference by electromagnetic fields. However, locations in
close proximity to radio/radar transmitters, heavy electrical plant and high voltage power cables
may experience field strengths in excess of those specified in EN50082. Where possible, such
locations should be avoided or units should be installed as far as possible from the source of
the electromagnetic field. Measures including additional screening, filtering and transient
suppression may also be of benefit in such locations.
3.2.3 Beam Path
The Transmitter and Receiver units windows should face each other across the area to be protected
and, depending on the range of the Transmitter in use, should be the following distance apart:
Excel Gas Detector type
Short Range
Medium Range
Long Range
Path length between units
5 - 40m (15 - 130ft)
40 - 120m (130 - 390ft)
120 - 200m (390 - 650ft)
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Searchline Excel