NonStop NS2200 Series Planning Guide

If you install a UPS other than the HP model R5000, R5500 XR or R12000/3 UPS in each modular
cabinet of a NonStop NS2200 system, these requirements must be met to insure the system can
survive a total AC power fail:
• The UPS output voltage can support the HP PDU input voltage requirements.
• The UPS phase output matches the PDU phase input. For details, see Chapter 4 (page 56).
• The UPS output can support the targeted system in the event of an AC power failure. Calculate
each cabinet load to insure the UPS can support a proper ride-through time in the event of a
total AC power failure. For more information, see “Enclosure Power Loads” (page 73).
NOTE: A UPS other than the HP model R5000, R5500 XR or R12000/3 will not be able
to utilize the power fail support of the Configure a Power Source as UPS OSM action.
IMPORTANT: You must change the ride-through time for an HP-supported UPS from the
manufacturing default setting to an appropriate value for your system. During installation of a
NonStop NS2200 system or HP UPS, your service provider can refer to the "Setting the Ride-Through
Time and Configuring for Maximized Runtime" procedure in the NonStop NS2200 Hardware
Installation Manual for these instructions.
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 NonStop NS2200 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 HP 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 “Heat Dissipation
Specifications and Worksheet” (page 84) to calculate the total heat dissipation for the hardware
installed in each cabinet. For air temperature levels at the site, see “Operating Temperature,
Humidity, and Altitude” (page 85).
Weight
Because modular cabinets for NonStop NS2200 systems house a unique combination of enclosures,
total weight must be calculated based on what is in the specific cabinet, as described in “Modular
Cabinet and Enclosure Weights With Worksheet” (page 82).
Cooling and Humidity Control 53