If your applications require a UPS that supports the entire system or even a UPS or motor
generator for all computer and support equipment in the site, you must plan the site’s electrical
infrastructure accordingly.
Cooling and Humidity Control
Do not rely on an intuitive approach to design cooling or to simply achieve an energy balance—that
is, summing up to the total power dissipation from all the hardware and sizing a comparable air
conditioning capacity. Today’s high-performance servers use semiconductors that integrate
multiple functions on a single chip with very high power densities. These chips, plus
high-power-density mass storage and power supplies, are mounted in ultra-thin server and
storage enclosures, and then deployed into computer racks in large numbers. This higher
concentration of devices results in localized heat, which increases the potential for hot spots that
can damage the equipment.
Additionally, variables in the installation site layout can adversely affect air flows and create hot
spots by allowing hot and cool air streams to mix. Studies have shown that above 70°F (20°C),
every increase of 18°F (10°C) reduces long-term electronics reliability by 50%.
Cooling airflow through each enclosure in the NS2100 system is front-to-back. Because of high
heat densities and hot spots, an accurate assessment of air flow around and through the server
equipment and specialized cooling design is essential for reliable server operation. For an airflow
assessment, consult with your Hewlett Packard Enterprise cooling consultant or your heating,
ventilation, and air conditioning (HVAC) engineer.
NOTE:
Failure of site cooling with the server continuing to run can cause rapid heat buildup
and excessive temperatures within the hardware. Excessive internal temperatures can result in
full or partial system shutdown. Ensure that the site’s cooling system remains fully operational
when the server is running.
Because each modular cabinet houses a unique combination of enclosures, use the
Dissipation Specifications and Worksheet” (page 69)
to calculate the total heat dissipation for
the hardware installed in each cabinet. For air temperature levels at the site, see
Temperature, Humidity, and Altitude” (page 70)
Weight
Because modular cabinets for NS2100 systems house a unique combination of enclosures, total
weight must be calculated based on what is in the specific cabinet, as described in
Cabinet and Enclosure Weights With Worksheet” (page 67)
Flooring
NS2100 systems can be installed either on the site’s floor with the cables entering from above
the equipment or on raised flooring with power and I/O cables entering from underneath. Because
cooling airflow through each enclosure in the modular cabinets is front-to-back, raised flooring
is not required for system cooling.
The site floor structure and any raised flooring (if used) must be able to support the total weight
of the installed computer system as well as the weight of the individual modular cabinets and
their enclosures as they are moved into position. To determine the total weight of each modular
cabinet with its installed enclosures, see
“Modular Cabinet and Enclosure Weights With Worksheet”
For your site’s floor system, consult with your Hewlett Packard Enterprise site preparation specialist
or an appropriate floor system engineer. If raised flooring is to be used, the design of the NS2100
system modular cabinet is optimized for placement on 24-inch floor panels.
Cooling and Humidity Control
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