Emerson Liebert Xtreme Density - Manual (Page 20)

Designing a Liebert XD Solution
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3.3 Selecting Liebert XD Cooling Modules
The next step is to select the Liebert XD cooling modules to be configured into the solution. Liebert
XD modules that use pumped refrigerant can be connected to the same Liebert XDP/Liebert XDC pip-
ing circuit. This includes the Liebert XDCF, Liebert XDH, Liebert XDO and Liebert XDV.
Generally, the Liebert XDO is selected for use in new installations or renovations where the unit can
be installed on the ceiling or in the overhead space.
The Liebert XDV is designed to permit mounting directly on top of an equipment cabinet, for ease of
installation in existing facilities. The Liebert XDV may also be suspended from overhead, using suit-
able mounting methods.
The Liebert XDCF is a self-contained module designed to cool Egenera’s BladeFrame EX cabinets and
equipment without exhausting heat into the room. Two modules may be mounted on the rear of a
BladeFrame cabinet.
The Liebert XDH is installed among equipment cabinets and is particularly suited to new installa-
tions.
3.4 Airflow Requirements for Liebert XD Solutions
Computer manufacturers typically specify a temperature change from intake to exhaust (delta T) of
18-27°F (10-15°C) for the air passing through a rack enclosure. The heat generated by electronic
equipment combined with the tight quarters of equipment cabinets mean that high volumes of air
must move through an enclosure to meet this cooling specification.
A Liebert XD system can supply the cooled air to satisfy this cooling demand, but airflow through the
enclosure must be adequate to extract the heat from the cabinet. Liebert’s XDA units can boost the
airflow to levels necessary to protect critical equipment. The Liebert XDA is particularly suited to the
hot aisle/cold aisle arrangement.
3.5 Configuring a Liebert XD System
3.5.1 Number of Modules Supported by a Liebert XDP or Liebert XDC
The numerals designating the model size of a Liebert XD unit may be used to configure a cooling sys-
tem. For example, a Liebert XDO20 has a model size of 20 and a Liebert XDP160 will accommodate
cooling modules with a cumulative model size of 160.
Similarly, the minimum number of modules connected to a Liebert XDP or Liebert XDC may be calcu-
lated using the model size number for the Liebert XDP or Liebert XDC and the modules. See Table 2.
Different types of Liebert XD cooling modules may be connected to the same Liebert XDP or Liebert
XDC as long as the sum of their cooling capacity does not exceed the supporting Liebert XDP’s or Lie-
bert XDC’s model size number.
Table 2 Maximum and minimum modules supported by a Liebert XDP or Liebert XDC
Cooling
Module Type
Liebert XDC Liebert XDP
Max Min Max Min
Liebert XDCF 16 6 16 4
Liebert XDH20 8 4 8 2
Liebert XDH32 5 2 5 1
Liebert XDO16 10 4 10 2
Liebert XDO20 8 4 8 2
Liebert XDV8 20 8 20 4
Liebert XDV10 16 7 16 4
NOTE
Connecting only Liebert XDCF modules to a Liebert XD unit is not recommended because the
Liebert XDCF heat loading is dependent on server airflow and server load. Consult factory to
determine if sufficient heat load is available from the server for the Liebert XD system to
operate effectively.