Digital Equipment StorageWorks UltraSCSI DS-BA370 Series, User Manual

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Power Distribution
6–2 UltraSCSI RAID Enclosure
______________________Note _____________________
Proper operation of the controller cache modules requires
external cache batteries (ECBs). The array controller
documentation discusses how to use the ECBs.
________________________________________________
Power System Overview
In any RAID subsystem a consideration is the elimination of single
points of failure. Designing systems with redundant power capabilities is
one way to accomplish this.
The following are the major components of the power system:
•
AC power sources
•
Power controllers
•
Power cords
•
Shelf power supplies
______________________Note _____________________
The power controller power cords are integral to the data center
cabinets. For the departmental server cabinets the user–supplied
power cords are country–specific.
The SBB shelf ac power cords are integral parts of the
UltraSCSI enclosures.
________________________________________________
Power Configurations
For all StorageWorks products with the capability of using redundant
power, the power configurations definitions are in the format n+x. In this
format, n is the minimum number of supplies required for operation, and x
is the number of redundant supplies. The UltraSCSI enclosures require a
minimum of four (n) supplies.
Standard (n+1)
This configuration has one redundant power supply for a total of five power
supplies. A single power controller distributes ac power to the five supplies
on power bus A. This configuration requires only one ac power source.