Sun Microsystems Sun Fire 12K, Site Planning Manual

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3-1
C H A P T E R
3
Facility and System Requirements
3.1 Facility Power Requirements
To prevent catastrophic failures, the design of the power system must ensure
that adequate power is provided to your Sun Fire 15K/12K systems.
Sun
Microsystems suggests that all power circuits supplying power to the Sun Fire 15K/12K
systems be derived from dedicated electrical distribution panels.
Electrical work and
installations must comply with applicable local, state, or national electrical codes.
Caution – System earth fault protection relies on the building circuit.
Sun Microsystems makes every effort to minimize the effects of power failures and
interruptions to the hardware. The Sun Fire 15K/12K systems have dual, redundant,
current-sharing power supply inputs, and are designed to use two independent
power sources. However, if the computer equipment is subjected to repeated power
interruptions and fluctuations, it is susceptible to a higher component failure rate
than it would be with a stable power source. Provide a stable power source, such as
an uninterruptible power system (UPS), to reduce the possibility of component
failures.
The power supplies of the Sun Fire 15K/12K systems incorporate an inrush current
limitation after the first power on. The maximum inrush current is 50 amps peak,
during hot or cold start (after the AC has been removed for 60 seconds) and 30 amps
RMS, hot or cold, when measured over one line cycle. The inrush current decays to
its normal operating current in less than 200 ms.
Every Sun Fire 15K/12K system cabinet and customer selected I/O expansion rack
requires its own customer-supplied circuit breakers and receptacles. Ensure the
power receptacles are within 14 ft (427 cm cable length) of the system cabinet and
each customer selected I/O expansion rack location.