Line Voltage; Branch Circuit Breakers; Three-Phase Branch Circuit Breakers; Single-Phase Branch Circuit Breakers - HP StorageWorks XP12000 - Disk Array Site Preparation Manual

Line voltage

Line voltage (AC) at the wall power outlet is a function of the local power utility and your building
power distribution network. Voltages outside of the operating range of the HP system can cause
intermittent system errors or a complete system shutdown. If required, an HP representative and your
electrician can determine the current line voltage and make recommendations. See
"Electrical specifications" on page 49 for specific AC line voltage requirements.
Avoid the use of a line voltage conditioner.
Make sure that a power distribution unit (if used) provides the correct voltage to support your entire
system.

Branch circuit breakers

See "Electrical
situation.

Three-phase branch circuit breakers

The power cords supplied with each DKC or DKU configured for three-phase power are sized for
connection to a 30-amp circuit.

Single-phase branch circuit breakers

The power cords supplied with each DKC or DKU configured for single-phase power are sized for
connection to a 30- or 50-amp circuit.
Note that 30-amp, single-phase power is available by special order only.

Frequency

Usually, AC line frequency is determined by your local power providers. In some cases, electrical
power is supplied by generators. Shifts in AC line frequency can cause system errors. An HP
representative can monitor the frequency of the input AC line power and make recommendations, if
necessary. The HP system requires that the line frequency be within 0.5 Hz of the rated line frequency
(50 Hz or 60 Hz).
See "Electrical

Safety and dedicated ground

The primary reason for grounding electrical systems is safety. The safety ground is required by the
National Electric Code (USA) and most other local, regional, and national codes. In addition to safety
ground, HP requires that a dedicated (earth reference) ground be installed as a common reference
point for all system components. Consult with an HP representative and your electrician to ensure that
your electrical system meets all local and national safety codes.

Grounding requirements

Your site's electrical subsystem must meet all of the following conditions:
• Earth grounding as prescribed by your local country codes.
specifications" on page 49 for specific branch circuit requirements for your power
specifications" on page 49 for more information.
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