Sun Microsystems Blade 8000 Series, Site Planning Manual

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6 Sun Blade 8000 Series Site Planning Guide • February 2008
Cooling Requirements
Every watt of power used by the system is dissipated into the air as heat. The
thermal power dissipation of the chassis in a 9000W N+N (Sun Blade 8000 Modular
System) or N+1 (Sun Blade 8000 P Modular System) configuration is 30,735 BTU/hr.
This requires that the data center heating, ventilation, and air conditioning (HVAC)
system must accommodate the maximum heat release of a fully configured system,
as well as any other systems in the data center.
The amount of heat output per Sun Blade 8000 Series system varies, depending on
the system configuration. The systems are equipped with fans that route cool air
throughout the chassis from front to rear. The maximum airflow through the chassis
is 1500 cfm.
As long as the necessary air conditioning is provided in the data center to dissipate
the heat load, and sufficient space and properly vented door openings are provided
at the front and back of rackmounted systems (see
TABLE 1
), the system fans will
enable the system to work within the temperature specifications for systems in
operation as noted in
TABLE 7
. Thermal characteristics of the Sun Blade 8000 Series
systems are provided in
TABLE 9
.
Temperature and Humidity Requirements
Avoid temperature and humidity extremes. The operating and nonoperating
temperature specifications listed in
TABLE 7
reflect the systems’ hardware limits, in
order to meet all functional requirements. Note that the operating temperatures
apply to the air entering the system and not necessarily to the temperature of the air
in the aisles.
The optimum operating ambient temperature and humidity ranges are the
recommended operating environment. Operating the system within the ambient
temperature range is optimal for system reliability. At 22
o
C (71.6
o
F) it is easy to
maintain safe relative humidity ranges and to provide a buffer in the event of an
environmental support system failure.
Ambient relative humidity levels between 45% and 50% are the most suitable for
system operations to:
■
Prevent corrosion.
■
Provide an operating time buffer in the event of an environmental control system
failure.
■
Help avoid system failures due to intermittent interference from static discharges
that can occur when relative humidity is too low. Electrostatic discharge (ESD) is
easily generated and less easily dissipated in areas where the relative humidity is
below 35%, and becomes critical when levels drop below 30%.
Conditions should not be allowed to fluctuate by more than 5.5
o
C (10
o
F) or 10%
relative humidity during a 60-minute period.