For more information about PDUs, see the IBM Redbooks Product Guides that
are available at this website:
http://www.redbooks.ibm.com/portals/systemx?Open&page=pg&cat=power
5.1.3 UPS units
There are several rack-mounted UPS units that can be used with the NeXtScale
systems, which are listed in Table 5-4. In larger configurations, UPS service is
often supplied at the data center level.
Table 5-4 UPS units for use with IBM NeXtScale System
Part number
53959KX
21304RX
53956AX
53956KX
For more information about UPS units, see the IBM Redbooks Product Guides
that are available at this website:
http://www.redbooks.ibm.com/portals/systemx?Open&page=pg&cat=power
5.2 Cooling
Cooling is an important consideration in designing any server solution. It can
require careful planning for large-scale environments. After the power planning is
done, calculating the amount of heat to be dissipated is relatively straight
forward. For each W of power that is used, 3.414 British Thermal Units per hour
(BTU/hr) of cooling is required.
What is more difficult to determine is the volume of air, commonly measured in
cubic feet per minute (CFM), that is required to cool the servers. The following
factors influence the air volume requirement of the servers:
The intake air temperature, which affects how much air is required to cool the
components to an acceptable temperature.
Humidity, which affects the air's thermal conductivity.
Altitude and barometric pressure, which affect air density.
Airflow impedance in the environment.
122
IBM NeXtScale System Planning and Implementation Guide
Description
IBM 11000 VA LCD 5U Rack UPS (200 V/208 V/230 V)
IBM UPS 10000XHV
IBM 6000 VA LCD 4U Rack UPS (200 V/208 V)
IBM 6000 VA LCD 4U Rack UPS (230 V)