Alcatel-Lucent 7705 SAR-A, Руководство по установке

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Installation Site Assessment
60 7705 SAR-A Chassis Installation Guide
Installation Site Type
The site must provide the appropriate environment for the installed equipment. This usually
involves controlling ingress of contaminants and ensuring that humidity remains as low as
possible.
Installations are typically in a hut, parking garage, room, or cabinet. Installation in data
centers or telecom centers do not usually have high pollution levels but could still have high
humidity levels.
Room
Is the room connected to the heating, ventilation, and air conditioning (HVAC) system of the
building? What protection is there to prevent ingress of dust, pollution, and humidity? To seal
the environment properly, ensure that any doors, windows, vents, holes, or conduits are
sealed or gasketed appropriately to ensure that the HVAC system can control the
environment. These must be checked as part of routine site maintenance.
If outside air is brought in for ventilation, does it pass through a filter? What is the type and
rating of the filter? Filters can help but the type of filter must be appropriate for the pollutants
you are trying to exclude. For example, a standard fiberglass type air filter only prevents large
debris and dirt from entering, but will do nothing to prevent entry of small particles (such as
ASSP), humid air or gaseous contaminants. It is important to understand the local conditions
and consider what type of filtering is most appropriate. Minimum Efficiency Reporting Value
(MERV) charts may serve as a good source to understand particle sizes and filter options.
One simple yet effective way to keep pollutants out is to ensure that positive pressure is
maintained inside the room or cabinet as compared to the outside by having fans blowing
properly filtered air into the room.
Does the site have an air conditioner or dehumidifier? Is the rating and capacity adequate for
the space? Where does the dehumidifier or air conditioner water drainage go?
Humidity reduction is one of the key elements in corrosion control. Air conditioners and
dehumidifiers are recommended to reduce local relative humidity at the site. Another method
is to keep the temperature in the cabinet high enough to maintain the relative humidity at less
than 50%. Condensate, if allowed to stay in the site or enclosure, will evaporate over time and
lead to higher relative humidity and corrosion.