4. On each RAID controller, remove the nut that holds the power cable
strain-relief clamp, and then remove the strain-relief clamp.
5. Wrap the strain-relief clamp around the line jumper power cord approximately
20 cm (8 in.) from the RAID controller connection end. Leave some slack
between the clamp and the RAID controller end of the line jumper power cord.
6. Replace the strain-relief clamp, and then tighten it securely with the nut.
7. Connect the other end of the line jumper cords to two independent
IBM-approved power distribution units in the rack cabinet. Connecting each
RAID controller to independent power sources maintains power redundancy. If
applicable, repeat this step for each additional storage subsystem and storage
expansion enclosure.
8. Connect the right and left power supplies of the attached storage expansion
enclosures to the same IBM-approved power distribution units in the rack
cabinet. For more information, refer to the
Installation, User’s, and
Maintenance Guide
for your DS4000
®
or DS5100 and DS5300 storage
expansion enclosures.
9. If you have not already done so, connect the primary power cables from the
rack cabinet to the external power source.
Note:
To maintain power redundancy, plug the PDUs that power the storage
subsystem’s right and left RAID controllers and the right and left power
supplies of the DS4000 or DS5100 and DS5300 storage expansion
enclosures into two independent external power circuits through ac
distribution units inside a rack cabinet or directly into external
receptacles.
Determine the maximum surge current possible when all devices in the
power circuit are started at the same time. Based on the total number of
devices on a power circuit, find the maximum (worst-case) specification
value in order to prevent the circuit from tripping. When both RAID
controllers are connected and the storage subsystem is powered on,
each RAID controller unit will handle approximately one-half of the
current load. To ensure maximum protection against power loss due to
RAID controller unit failure or a power circuit tripping, both RAID
controller units must be connected and powered on. See Table 16 on
page 29 for the DS5100 and DS5300 ac power requirements.
Do not overload the circuits that power your storage subsystem and
storage expansion enclosures. Use additional pairs of IBM-approved
power distribution units (PDUs) if necessary.
See Figure 89 on page 125 for an example of redundant power cabling.
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IBM System Storage DS5100 and DS5300 Storage Subsystem: Installation, User’s, and Maintenance Guide
