3PAR InServ® E-Class/F-Class Storage Server Physical Planning Manual (320 - 200120 Rev F, September 2010)

5.14
3PAR InServ E-Class/F-Class Storage Server Physical Planning Manual
5.8 Branch Circuits
The individual panel branch circuits should be protected by suitable circuit breakers properly
rated according to manufacturer specifications and applicable codes. Each circuit breaker
should be labeled to identify the branch circuit it is controlling. The receptacle should also be
labeled. Plan on a circuit breaker maximum of 30 A per PDU (de-rated to 24 A).
5.9 Emergency Power Control
As a safety precaution, you might consider providing emergency power-off controls for
disconnecting the main service wiring that supplies the InServ Storage Servers. Install these
controls at a convenient place for the operators and next to the main exit doors of the room
after checking local electrical codes for further guidelines.
5.10 Redundant Power
The E-Class/F-Class controllers and storage arrays are designed to continue operating even
when AC power is lost to one of its supplies. For this feature to operate properly, each power
supply line cord within an enclosure must be attached to a separate branch circuit, each
controlled and protected by its own circuit breaker. Multiple outlets in a power distribution
unit or power strip do not constitute a separate branch circuit.
Additionally, each line cord must be plugged into an outlet that is capable of supporting the
entire load of its enclosure.
Table 5-4 lists the maximum current draw per outlet as a function of common line voltages.
The maximum load means the total load for the enclosure. When both power supplies are
working, each supply takes half the power load. In the event of a power failure, the working
supply takes the entire load.
CAUTION: In site planning, it is critical that special consideration is given to this
requirement. Failure to do so might result in the overloading of the branch circuit
if a power supply failed, which could shut down the server components and cause
similar failures in all the equipment connected to that branch circuit.