HP 3PAR InForm OS 3.1.1 Messages and Operators Guide

NOTE: In the T800, PDUs are positioned back-to-back so that they only take up 2U of space at
the bottom of the cabinet rather than the standard 4U of space. PDUs are accessible from both the
front and the rear of the storage system. “Controller Node Cabinet Component Layout” (page 12)
illustrates PDU placement for the T800.
Each PDU has two power banks, each with a separate circuit breaker, to be used exclusively for
storage system components (Figure 8 (page 39)).
Figure 8 Power Banks in the PDU
WARNING! To avoid possible injury, damage to storage system equipment, and potential loss
of data, do not use the surplus power outlets in the storage system PDUs. Never use outlets in the
PDUs to power components that do not belong to the storage system or to power storage system
components that reside in other cabinets.
NOTE: For more information on PDUs and storage system configurations, see the T-Class Storage
System Installation and Deinstallation Guide .
Battery Backup Unit Numbering
The controller node cabinet includes one or two battery trays that hold the battery backup units
(BBU). The BBUs supply enough power to write the cache memory to the IDE drive inside the nodes
in the event of a power failure. One battery per controller node is required for all storage system
configurations. BBU placement and numbering schemes vary according to the type of components
used in the system.
There is always a battery tray located directly below the backplane. When a second battery tray
is required, as is the case with storage systems that have six or eight controller nodes, a second
battery tray rests immediately above the backplane.
Storage systems use Magnetek BBUs. Each battery unit contains two independently-switched
batteries, labeled battery a and battery b (Figure 9 (page 14)).
Figure 9 Battery Backup Unit
14 Component Numbering for T-Class Storage System