Storage Expansion Enclosure Features; Heat Output, Airflow, And Cooling - IBM TotalStorage DS4000 EXP700 Installation, User's, And Maintenance Manual

Storage expansion enclosure features

The following features are available with this product.
Table 12. Storage expansion enclosure features
Power supply
v Two 400 W hot-pluggable power supplies
v Power supplies are accessible from the
v Two ac line cords
v Two 9-ft jumper cords
v On/off switch on the back of each power
v 14 disk drives run continuously from a
Two fan units
v Hot pluggable fan units accessible from the
v Two fan units, with two fans per unit, for a

Heat output, airflow, and cooling

The maximum heat output of the storage expansion enclosure is 390 watts (1088
BTU/hr). Each rack-mounted storage expansion enclosure requires an airflow of 2.5
m
10° C - 35° C (50° F - 95° F).
Note: In general, storage expansion enclosure reliability tends to decrease as the
When racks that contain many storage expansion enclosures are to be installed
together, the following requirements must be met to ensure that the storage
expansion enclosures are adequately cooled:
v Air enters at the front of the rack and leaves at the back. To prevent the air that
v Where racks are in rows, each rack must touch the rack that is next to it to
v Where racks are in rows front-to-front or back-to-back, a gap of at least 1220 mm
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IBM TotalStorage DS4000 EXP700 and EXP710 Storage Expansion Enclosures: Installation, User's, and Maintenance Guide
rear using camming levers or latches.
supply
single power supply.
rear of the storage expansion enclosure,
one on each side
total of four fans. The fans are redundant,
meaning that if one fan is disabled the
remaining three fans continue to cool the
storage expansion enclosure.
3 3
(87 ft ) per minute. The input air temperature to all racks should be in the range
ambient temperature of the environment in which it is being used increases.
The ambient temperature in the immediate area of the storage expansion
enclosure should be kept near 22 degrees C (72 degrees F), or lower, to
provide better reliability.
is leaving the rack from entering the intake of another piece of equipment, you
must position the racks in alternate rows, back-to-back and front-to-front. This
arrangement is known as "cold aisle/hot aisle" and is shown in Figure 9 on page
15.
reduce the amount of hot air that can flow around from the back of the rack into
the intakes of the storage expansion enclosures that are in that rack. You should
use Suite Attach Kits to completely seal any gaps that remain between the racks.
For details about Suite Attach Kits, contact your marketing representative.
(48 in.) must separate the rows across the cold aisle.
Environmental service module (ESM)
v Two ESMs are accessible from the back of
the storage expansion enclosure.
v ESMs are hot pluggable.
v ESMs are redundant.