Technical Specifications
Designing a Liebert XD Solution
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3.10 Liebert XDV Module Placement
Liebert XDV modules should be placed on top of the cabinets that generate the greatest amount of
heat. If heat loads are dispersed evenly throughout the room, the Liebert XDV modules may be
spread out accordingly.
The Liebert XDV must be placed toward the front of the equipment cabinet, so that its front bottom
edge is flush with the front top edge of the cabinet. Placing the module farther back on the top of the
cabinet will restrict airflow into the cold aisle. Placing the module too far toward the front of the
cabinet will decrease the amount of hot air drawn into the module.
Figure 19 Positioning Liebert XDV on top of cabinet
Both of the Liebert XDV’s power cords should be connected to power sources. If only one power source
is available, then only the power cord labeled “SECONDARY” should be connected to the power
source.
Piping for the Liebert XDV is routed upward to the main return and supply pipes to and from the
Liebert XDP/Liebert XDC.
Table 7, below, may be used to determine the correct number of Liebert XDV modules.
Table 7 Determine required number of Liebert XDV modules (example below is Liebert XDV10)
Input Information Step Results
Total heat load in the room, kW A
Reserve capacity needed
(10% - 25% of A is recommended)
B
C Required cooling capacity, kW = A + B
Existing/planned Liebert
Deluxe/DS sensible capacity, kW
D
E Required Liebert XD system cooling capacity, kW = C – D
F
Number of Liebert XDV10 modules required = E ÷ 10, rounded up (60Hz)
= E ÷ 8, rounded up (50Hz)
G
Number of Liebert XDP/Liebert XDC units required = F ÷ 16,
rounded up (60Hz and 50Hz)
Room area, square feet H
I Area served by each Liebert XDV10 = H ÷ F
L
Required Liebert XD system cooling density = E x 1000 ÷ H
OK if under 580 for 12-foot cold aisle spacing
OK if under 435 for 16-foot cold aisle spacing
Otherwise, additional Liebert Deluxe or Liebert DS capacity is needed.
INCORRECT
Liebert XDV
hangs over front
edge of rack
INCORRECT
Liebert XDV is
too far from front
edge of rack
CORRECT
Liebert XDV is flush with
front edge of rack
X
Liebert XDV is suspended from
ceiling structure...
X
....the separation
between the rack and
the Liebert XDV
should be held to less
than 1" (25mm). If this
is not possible, an air
blocker should be
added to prevent
unwanted airflow
between the hot aisle
and the cold aisle.