MSA Senscient ELDS 1000 series, Руководство по эксплуатации

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Installation Design & Engineering
Senscient ELDS™
Rev 15 33
GB
3.2.3 Location to Maximise Reliability and Availability
Care in choosing the location of ELDS™ OPGDs 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 ELDS™ OPGD 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 - ELDS™ OPGDs are certified and specified for operation in environments up to
+60°C. If sources of intense heat (flarestacks, intense sunlight, etc.) are present, the effect of
these will be reduced by the fitted sunshade. If the sunshade proves insufficient in an extremely
hot installation (greater than 35°C) then further shielding should be provided or the detector should
be relocated.
Sources of Heavy Contamination
- Avoid locations where high levels of contaminants will
persistently be blown onto the unit’s lens-windows. Potential sources of heavy contamination
include generator/turbine exhausts, flare-stacks, 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 ELDS™ OPGD units will melt
snow or ice on the lens-windows in ambient temperatures down to approximately 20°C. Below this
temperature, snow or ice blown onto the lens-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.
Deluge and Flooding
- Senscient ELDS™ OPGDs are 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 ELDS™ OPGD units be located away from areas particularly
prone to deluge or flooding.
Areas Prone to Subsidence and Settling
- Where possible, it is recommended that ELDS™
OPGD 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 ELDS™ OPGD will become misaligned with respect to each
other. Provided that the ELDS™ OPGD 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 ELDS™ OPGDs are visited and their alignment be checked.
Accidental Impact
- Mount Transmitter and Receiver horizontally to protect from impact.
Locations where there is a likelihood of equipment, personnel or moving objects accidentally
knocking ELDS™ OPGD units out of alignment should be avoided. If such locations cannot be
avoided, measures including improved mechanical protection and warning notices should be
considered.