Frequently-Asked Questions - HP Surestore Disk Array 12h - And FC60 Service Manual

Appendix D. Back-to-Back Racking

Frequently-asked Questions

Frequently-asked Questions
What site preparation is required?
Power. There must be a source of 240 VAC power for each of the rack's two PDUs. Each PDU draws a
maximum of 16A. European locations may require upgraded circuit breakers, as described in the previous
section. Redundant power configurations require redundant power sources (that is, power to the rack's two
PDUs must come from separate circuits).
Location. The rack location must allow sufficient clearance for access to array enclosures and access to
service. Normally, about 2 feet (0.61 meters) clearance between the rack's back and any wall is sufficient.
Does the installation change the height of the rack?
Yes. Installing the Exhaust Fan Assembly increases the height of both the 1.6 meter rack and the 2.0 meter
rack by 1 EIA unit (1.75" or 44.45 mm).
Do I have to use filler panels?
Yes. If the rack is not fully populated with array enclosures, you must install enough filler panels to close
the remaining open spaces in the front and back of the rack. This is to optimize cooling efficiency.
What if I have an uninterruptible power supply (UPS) at my site?
The indicator LEDs are unlikely to report power outage conditions. They will still report power outage
conditions if power from the UPS to the rack PDUs has failed. They will still report fan failure conditions.
How do I rack less than the maximum number of array enclosures?
For optimum cooling efficiency, array enclosures should be racked from top to bottom in the front of the
rack and from bottom to top in the back of the rack. If side access to the rack is not going to be possible,
install the bottom and then the top array enclosure, leaving the array position in the middle or top, open
(middle for a 2-meter rack or top for a 1.6 meter rack).
What replacement parts are there?
The only replacement part is the exhaust fan assembly (part number E7687-63001). A failed exhaust fan
assembly must be replaced by the Hewlett-Packard service provider.
How rapidly must I replace a failed exhaust fan assembly?
One failed fan in an exhaust fan assembly will not cause a critical cooling condition immediately.
However, it's best to replace the exhaust fan assembly as soon as possible. For racks fully-populated with
disk storage units, replace the exhaust fan assembly within 48 hours.
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