User's Manual

Σd
component
W = d
system cg
W
where d
component
= the distance of interest and W = Weight
The distance of a component is its CG’s distance from the inside base of the cabinet. For example,
if a loaded disk enclosure is to be installed into the cabinet with its bottom at 10U, the distance
for the enclosure would be (10*1.75)+2.7 inches.
Airflow and recirculation
Component airflow requirements
Component airflow must be directed from the front of the cabinet to the rear. Components vented
to discharge airflow from the sides must discharge to the rear of the cabinet.
Rack airflow requirements
The following requirements must be met to ensure adequate airflow and to prevent damage to the
equipment:
• If the rack includes closing front and rear doors, leave 830 inches
2
(5,350 cm
2
) of open
space evenly distributed from top to bottom to permit adequate airflow (equivalent to the
required 64% open area for ventilation).
• For side vented components, the clearance between the installed rack component and the
side panels of the rack must be a minimum of 2.75 inches (7 cm).
• Always use blank panels to fill empty front panel U-spaces in the rack. This ensures proper
airflow. Using a rack without blank panels results in improper cooling that can lead to thermal
damage.
Configuration standards
EVA configurations are designed considering cable length, configuration CG, serviceability and
accessibility, and to allow for easy expansion of the system. If at all possible, it is best to configure
non-HP cabinets in a like manner.
UPS selection
This section provides information that can be used when selecting a UPS for use with the EVA. The
four HP UPS products listed in Table 22 (page 124) are available for use with the EVA and are
included in this comparison. Table 23 (page 124) identifies the amount of time each UPS can sustain
power under varying loads and with various UPS ERM (Extended Runtime Module) options.
NOTE: The specified power requirements reflect fully loaded enclosures (14 disks) .
Table 22 HP UPS models and capacities
Capacity (in watts)UPS Model
1,340R1500
2,700R3000
4,500R5500
12,000R12000
Table 23 UPS operating time limits
Minutes of operation
Load (percent)
With 2 ERMsWith 1 ERMWith standby battery
R1500
49235100
124 Non-standard rack specifications