IBM TotalStorage DS4100, Installation, User'S, And Maintenance Manual

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Table 10. IBM TotalStorage DS4100 AC power requirements
Low Range High Range
Nominal Voltage 90 to 136 VAC 180 to 264 VAC
Frequency 50 to 60 Hz 50 to 60 Hz
Idle Current 2.50 A
a
1.33 A
b
Maximum Operating Current 3.01 A
a
1.57 A
b
a.
Typical voltage: 115 V AC, 60 Hz at 77% power-supply efficiency and 0.96 power factor
b.
Typical voltage: 230 V AC, 60 Hz at 77% power-supply efficiency and 0.96 power factor
Heat output, airflow, and cooling
The maximum heat output of the DS4100 is 390 watts (1235 BTU/hr). Each
DS4100 rack-mounted unit requires an airflow of 2.5 m
3
(87 ft
3
) per minute. The
input air temperature to all rack cabinets should be in the range 10° C - 35° C (50°
F - 95° F). The recommended operating temperature is 22° C (72° F).
When rack cabinets that contain many DS4100s are to be installed together, the
following requirements must be met to ensure that the DS4100s are adequately
cooled:
v
Air enters at the front of the rack cabinet and leaves at the back. To prevent the
air that is leaving the rack cabinet from entering the intake of another piece of
equipment, you must position the rack cabinets in alternate rows, back-to-back
and front-to-front. This arrangement is known as “cold aisle/hot aisle” and is
shown in Figure 8 on page 16.
v
Where rack cabinets are in rows, each rack cabinet must touch the rack cabinet
that is next to it to reduce the amount of hot air that can flow around from the
back of the rack into the intakes of the storage servers that are in that rack
cabinet. You should use Suite Attach Kits to completely seal any gaps that
remain between the rack cabinets. For details about Suite Attach Kits, contact
your marketing representative.
v Where rack cabinets are in rows front-to-front or back-to-back, a gap of at least
1220 mm (48 in.) must separate the rows across the cold aisle.
v
To ensure correct airflow in each rack cabinet, the rack filler plates must be
installed in unused positions. Also, all the gaps in the front of the rack cabinets
must be sealed, including the gaps between the storage servers.
Chapter 1. Introduction
15