Table of Contents
Advertisement
MAN0889_Issue 3_03/13
3. Installation and Operation
3.2.3 Location to Maximise Reliability and Availability
For optimum performance, take care to avoid areas where the units 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.
Mounting Rigidity – The duct wall thickness should be suitable to maintain rigidity of the Searchline Excel
Cross-Duct mounting to within ±0.5°.
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 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. 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.
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.
Since the Transmitter and Receiver protrude from the duct wall, adequate precautions should be taken to
protect personnel.
Intense Electromagnetic Fields - Searchline Excel Cross-Duct complies with EN50270 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 the standard. 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.
To ensure optimum performance, do not cover the Excel with insulation, and allow free air movement around
the unit.
3.2.4 Beam Path
The path of the infrared beam inside the duct is unlikely to be affected by obstructions, however, consideration
should be given to avoid:
•
Steam vents
•
Splash and spray
Searchline Excel Cross-Duct Technical Handbook
13
Advertisement
Table of Contents
