Technical Specifications

Designing a Liebert XD Solution
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3.4.2 System Connection Configuration
If possible, connect the Liebert XD modules to Liebert XDPs or Liebert XDCs in an interlaced
configuration (see Figure 13). In an interlaced configuration, half the cooling modules in an aisle are
connected to one Liebert XDP or Liebert XDC and the other half in that aisle are connected to another
Liebert XDP or Liebert XDC. Interlacing the connection piping will keep half the Liebert XD modules
operating and maintain cooling in the conditioned space should one of the Liebert XDP or
Liebert XDC units fail.
Figure 13 Typical Liebert XDR piping—interlaced connections
3.5 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 high volumes of air must
move through an enclosure to meet this cooling specification.
A Liebert XD system can supply the cold 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.
Return
Supply
Liebert XDP /
Liebert XDC A
Liebert
XD Module A
Liebert
XD Module B
TOP VIEW
Return
Supply
Liebert XDP /
Liebert XDC B
NOTE: Line size does NOT
indicate pipe size difference .
Liebert
XD Module B
Liebert
XD Module B
Liebert
XD Module B
Liebert
XD Module A
Liebert
XD Module A
Liebert
XD Module A
DRAWING IS
NOT TO SCALE