232 IBM ^ zSeries 990 Technical Guide
9.1 Introduction
The z990 is always a two-frame system. The frames are shipped separately and are fastened
together when installed.
Installation of a z990 is always on a raised floor. The number of cables to be expected for
most configurations may be so large that installation is only possible with space underneath.
The dimensions of a z990 are slightly smaller than that of a two-frame z900 and its maximum
weight is slightly higher.
9.1.1 Power and cooling requirements
The z990 requires at least two power feeds and uses two redundant three-phase line cords,
allowing the system to survive the loss of power to either one. In case of a power failure of
one of the line cords, the other one is able to take over the entire load to keep the system
operating without interruption. The z990 is installed with three-phase wiring and operates with
50/60Hz AC power, and voltages ranging from 200V to 480V. For ancillary equipment (like the
Hardware Management Console, its display, and the modem), additional single-phase outlets
are required.
9.1.2 Power consumption
Actual power consumption is dependent on the server configuration in terms of the number of
books and the number of I/O cages installed. The figures listed in Table 9-1 assume the
maximum configuration.
Table 9-1 Power consumption and heat load
Input power in kVA is equal to the output power in kW. Heat output expressed in kBTU per
hour is derived by multiplying the table entries by a factor of 3.4.
The maximum allowed circuit breaker rating is 60 Amps, which is to be used for both power
feeds where 200-240V is applicable. Where 380-480 Volts is applicable, 30 Amps are
recommended for both power feeds.
9.1.3 Internal Battery Feature
The optional Internal Battery Feature (IBF) provides sustained system operations for a
relatively short period of time, allowing for orderly shutdown. In addition, an external UPS
system can be connected to the z990, allowing for longer periods of sustained operation.
The Internal Battery Feature, given that the batteries are not older than three years and have
been discharged regularly, are capable of providing emergency power for the periods of time
shown in Table 9-2 on page 233.
Model One I/O cage Two I/O cages Three I/O cages
IBM 2084 model A08 6.74 kW 10.64 kW 13.81 kW
IBM 2084 model B16 9.57 kW 13.27 kW 16.98 kW
IBM 2084 model C24 11.82 kW 15.53 kW 19.23 kW
IBM 2084 model D32 13.98 kW 17.68 kW 21.39 kW
Get IBM eServer zSeries 990 Technical Guide now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
