6
Sun Netra X4250 Server Site Planning Guide • May 2010
Ambient Temperature
An ambient temperature range of 21˚C (69.8˚F) to 23˚C (73.4˚F) is optimal for server
reliability. At 22˚C (71.6˚F) it is easy to maintain safe relative humidity levels.
Operating in this temperature range provides a buffer if the environmental support
systems fail.
Ambient Relative Humidity
Ambient relative humidity levels between 45% and 50% are the most suitable for
data processing operations in order to:
■
Prevent corrosion
■
Provide an operating time buffer in the event of environmental control system
failure
■
Help avoid failures caused by the intermittent interference from static discharges
that 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%.
Airflow Considerations
■
Ensure unobstructed airflow through the chassis. The server uses internal blowers
that can achieve a total airflow of 120 CFM (3.4 m
3
/) in normal operating
conditions.
■
Ensure that inlet air enters at the front of the server and exits from the back.
■
Ensure that ventilation openings such as cabinet doors, for both the inlet and
exhaust of the server, provide a minimum open area of 35.5 in.
2
(231 cm
2
) each.
This size equates to a 60% open area perforation pattern across the front and rear
area of the server 17.4 in. x 3.4 in. (442 mm x 87.1 mm). The impact of other open
area characteristics that are more restrictive. You must evaluate.
■
Ensure that front and rear clearance of the server allow a minimum of 0.2 in. (5
mm) at the front of the server and 3.15 in. (80 mm) at the rear of the server when
mounted. These clearance values are based on the inlet and exhaust impedance
(available open area) stated in the third bullet assume a uniform distribution of
the open area across the inlet and exhaust areas. These values also improve
cooling performance.