IBM Power 595, Technical Overview And Introduction, Page: 43 / 188

Chapter 1. General description
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The acoustical front door and rear door heat exchanger kit provides both additional cooling
and acoustical noise reduction for use where a quieter environment is desired along with
additional environmental cooling. This feature provides a specially designed front acoustical
door and an acoustical attachment to the Rear Door Heat Exchanger door that reduce the
noise emissions from the system and thereby lower the noise levels in the data center.
Acoustically absorptive foam and unique air inlet and exhaust ducts are employed to
attenuate the noise.
1.4.2 Rear door heat exchanger
The Power 595 systems support the rear door heat exchanger (#6859) similar to the one
used in POWER5 based 590/595 powered system racks. The rear door heat exchanger is a
water-cooled device that mounts on IBM 24-inch racks. By circulating cooled water in sealed
tubes, the heat exchanger cools air that has been heated and exhausted by devices inside
the rack. This cooling action occurs before the air leaves the rack unit, thus limiting the level of
heat emitted into the room. The heat exchanger can remove up to 15 kW (approximately
50,000 BTU/hr) of heat from the air exiting the back of a fully populated rack. This allows a
data center room to be more fully populated without increasing the room's cooling
requirements. The rear door heat exchanger is an optional feature.
1.4.3 Power subsystem
The Power 595 uses redundant power throughout its design. The power subsystem in the
system rack is capable of supporting 595 servers configured with one to eight processor
books, a media drawer, and up to three I/O drawers.
The system rack and powered Expansion Rack always incorporate two bulk power
Assemblies (BPA) for redundancy. These provide 350 V dc power for devices located in those
racks and associated nonpowered Expansion Racks. These bulk power assemblies are
mounted in front and rear positions and occupy the top 8U of the rack. To help provide
optimum system availability, these bulk power assemblies should be powered from separate
power sources with separate line cords.
Redundant Bulk Power Regulators (BPR #6333) interface to the bulk power assemblies to
help ensure proper power is supplied to the system components. Bulk power regulators are
always installed in pairs in the front and rear bulk power assemblies to provide redundancy.
The number of bulk power regulators required is configuration-dependent based on the
number of processor MCMs and I/O drawers installed.
A Bulk Power Hub (BPH) is contained in each of the two BPAs. Each BPH contains 24
redundant Ethernet ports. The following items are connected to the BPH:
Two (redundant) System Controller service processors (SC),
One HMC (an additional connection port is provided for a redundant HMC)
Bulk Power Controllers
Two (redundant) Node Controller (NC) service processors for each processor book
The 595 power subsystem implements redundant bulk power assemblies (BPA), Bulk Power
Regulators (BPR, #6333), Power controllers, Power distribution assemblies, dc power
converters, and associated cabling. Power for the 595 CEC is supplied from dc bulk power
Note:
Many of our clients prefer the reduction of ambient noise through the use of the
acoustic door kit
.