Siting And Mounting - Honeywell Searchline Excel Technical Handbook

MAN0530 Issue 10 - 11/09
2104M0506
3. INSTALLATION AND OPERATION

3.2 SITING AND MOUNTING

3.2.1 General
When designing an installation for a Searchline Excel gas detector it is important to give
consideration to where it is to be located, what potential sources of problems may be encountered
in this location and how the unit is to be mounted and supported.
3.2.2 Location for Best Coverage
Guidance on the positioning of gas detectors to provide the best detection coverage is contained
in BS EN 60079-29-2:2007 & IEC 60079-29-2:2007 and other national Codes of Practice. It is
recommended that the installation designer consults these Codes of Practice when determining
where detectors are to be located. In general, the following positions usually provide the best
results:
• Below potential leak sources for gases that are heavier than air.
• Above potential leak sources for gases that are lighter than air.
• Near to leak sources, along the expected leak trajectory, taking account of the
prevailing wind direction and any other factors which will influence propagation
of the leak.
• Between possible leak sources and any potential sources of ignition.
location to maximise reliability and availability
Care in choosing the location of Excel detectors can contribute significantly to the overall
reliability and availability.
When locating units, attempt to avoid areas where they may be adversely affected by the
following:
vibration - Angular vibration of the structure to which Excel units are attached should be kept
to less than +/- 0.5°. Where possible, avoid locations where high levels of vibration will be
directly induced into the mounting structure. If close proximity to significant sources of vibration
is unavoidable, take steps to reduce coupling of this vibration and maximise the rigidity of the
mounting structure.
intense heat - Excel is certified and specified for operation in environments up to
+65°C. If sources of intense heat (flarestacks, intense sunlight, etc.) are present, a
sunshade (Part No: 2104B2323) or similar shield should be fitted to the unit to protect it
from excessive heating.
sources of heavy Contamination - Avoid locations where high levels of contaminants will
persistently be blown onto the unit's windows. Potential sources of heavy contamination include
generator/turbine exhausts, flarestacks, drilling equipment, process vents/chimneys etc. If
sources of heavy contamination cannot be avoided, consider fitting extra shielding and/or
providing good access for more routine cleaning.
snow and ice in ambients below -20°C - The heated optics on Excel units will melt snow or
ice on the windows in ambient temperatures down to approximately -20°C.
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Searchline Excel