HP 3PAR StoreServ 10000 Storage Physical Planning Manual

Figure 13 Hot-Aisle/Cold-Aisle Layout
Form rows of racks or cabinets perpendicular to air conditioners. This formation facilitates an
unobstructed flow of heated air down the aisles to the air conditioner return ducts. Heated air must
not be forced to travel over or between the cabinets to get to the air conditioner return ducts. Doing
so could heat the air in the cold aisles. Ensure that any free-standing equipment does not allow air
to flow between the hot and cold aisles.
A cold aisle has perforated floor tiles or grates that enable cold air to rise from the raised floor
whereas the hot aisle has no tiles or grates so that hot air and cold air do not mix. Seal cable
cutouts in both hot aisles and cold aisles to increase under the floor pressure and to eliminate cold
or hot air redirection. To further optimize the airflow in hot and cold aisles, install blanking panels
at the front of all unused cabinet spaces so that hot air does not recirculate to the system’s cold air
inlet.
Providing for Service Access
The storage system is housed in 2M (40U) cabinets that measure 76.75 in. (195 cm) x 23.60 in.
(60 cm) x 35.62 in. (90.5 cm). Cabinets feature locking rear doors and removable side panels
to improve access while installing, cabling, and servicing components.
NOTE: For cabinets using Single-Phase 3PAR PDUs, avoid placing the cabinets directly next to
each other. Leave approximately a 1/4 to 3/8 inch space in between each cabinet for proper
clearance to open rear security door.
When establishing an operating site for an storage system, provide for adequate access to cabinets
by following the access area recommendations in Table 5 (page 25).
NOTE: The storage systems have circuit breakers located at both the front and rear of the system.
It is necessary to maintain access to both the front and rear circuit breakers.
24 Structural/Environmental Considerations