NonStop NS1000 Planning Guide (H06.06+)

Installation Facility Guidelines
HP Integrity NonStop NS1000 Planning Guide—542527-002
2-4
Cooling and Humidity Control
You can order an optional HP R5500 XR UPS for each modular cabinet to supply
power to the enclosures within that cabinet. Extended runtime modules (ERMs) can be
included with the R5500 XR UPS to extend the power back-up time. 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.
For power information, refer to Model R5500 XR Integrated UPS on page 3-5. For
complete information and specifications on the R5500 XR UPS, contact your HP
representation or refer to the HP UPS R5500 XR Models User Guide available at:
http://h10032.www1.hp.com/ctg/Manual/c00065453.pdf
Cooling and Humidity Control
Do not rely on an intuitive approach to cooling design 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, which are 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 Integrity NonStop NS1000 server 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 HP
cooling consultant or your heating, ventilation, and air conditioning (HVAC) engineer.
Because each modular cabinet houses a unique combination of enclosures, use the
Heat Dissipation Specifications and Worksheet on page 3-9 to calculate the total heat
dissipation for the hardware installed in each cabinet. For air temperature levels at the
site, refer to Operating Temperature, Humidity, and Altitude on page 3-9.
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.