HP StorageWorks Disk Array XP1024: Site Preparation Guide (A7906-96013, July 2005)

Preparing for installation 47
Receptacles
When receptacles are used to connect your disk array components to AC
power, they must include a dedicated ground connection that is insulated
from the receptacle. It is important that the receptacle box be grounded with
an additional ground connection that is separate from the dedicated ground.
The additional ground can be hard conduit.
Each disk array cabinet has two or four separate connections to AC power
(except the 60-amp, three-phase DKC, which has no external power
connection). For disk array cabinets with two connections to AC power,
each input must be capable of supporting the entire current demand for the
cabinet. For disk array cabinets with four connections to AC power, the two
inputs to AC Box 1 or the two inputs to AC Box 2 must be capable of
supporting the entire current demand for the cabinet. The figure below
shows two examples of the disk array’s fault-tolerant operation.
Disk Array Cabinet
(DKU or DKC)
(2 AC Power
connections)
(4 AC Power
connections)
Disk Array Cabinet
(DKU or DKC)
The Disk Array can tolerate the loss
of connection to AC Box 1 or AC Box 2.
AC Power
Input Box
#2
AC Power
Input Box
#1
AC Power
Input Box
#2
AC Power
Input Box
#1
The D isk Array can tolerate the loss
of connections to AC Box 1 or AC Box 2,
but no other combinations are allowed.