Manual

Power supplies
The two power su
pplies mount in the rear of the enclosure. See Figure 16. The supplies are autoranging
and operate on
acountry-specific AC input voltage of 202 to 240 VAC ±10%, 50 to 60 Hz, ±5%, (188
to264VAC,47to63Hz).
The DC outputs of this power supply are:
• +5.1 VDC for th
eEMU,I/Omodule,backplane, and disk drives
• +12.1 VDC for the disk drives
• +12.5 VDC for the disk drives
Theoutputof
each power s upply is 499W, with a p eak output of 681W. A single power supply can
support an en
closure with a full complement of disks.
The power supply circuitry provides protection against:
• Overloads
• Short circu
its
• Overheating
Power supply status and diagnostic information is reported to the EMU with voltage, current, and
temperature signals.
See Regulatory Notices and Specifi cations for the enclosure power specifications.
The power su
pply temperature sensor provides a temperature range signal to the EMU, which uses this
signal to set the blower speed.
The power supply internal temperature c an also control the spee d of the b lower. The higher the power
supply temperature, the faster the speed of the blower. If the power supply temperature exceeds a preset
value, the power supply automatically shuts down.
Blowers
The p ower supply–mounted blowers cool the enclosure by circulating air through the enclosure. The
blowers, under the control of the EMU or the associated power supply, can operate a t multiple speeds.
This ensures that when the enclosure temperature changes the blowers can automa tically adjust the
air flow.
If a b lower is operating too slowly or has stopped (a “blower failure”), internal circuitry automatically
operates the remaining blower at a higher speed. Simultaneously, the error condition is reported in
several ways, including the power supply indicator, the audible alarm, the enclosure fault indicators,
and the EMU alphanumeric display.
Should both blowers fail, the power supplies automatically shut down.
NOTE:
The blowers are field-replaceable units and ca n be replaced, individually, while the system is running.
The blowers are also interchangeable. The failure of a power supply +12.5 VDC circuit disables the
associated blower.
The status indicator on the blower displays the status of both the power supply and the b lower. See
Figure 16.SeeTable 12 for definitions of the indicator displays.
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Enterprise Virtual Array hardware components