Sun Microsystems Enterprise 250 Owner's Manual page 122

when both supplies are installed, they share equally in satisfying the power demands
of the system.
Power supplies are modular units, designed for fast, easy installation or removal,
even while the system is fully operational. Supplies are installed in bays at the rear
of the system, as shown in the following figure.
Figure 5–9
The system can accommodate one or two power supplies. Each supply provides up
to 360 watts of DC power. All system configurations can operate with only one
power supply installed. A second supply can be used to provide N+1 redundancy,
allowing the system to continue operating should one of the power supplies fail.
Power supplies in a redundant configuration feature a "hot swap" capability. You
can remove and replace a faulty power supply without turning off the system power
or even shutting down the operating system.
Note -
When removing a hot-swappable power supply, do not disengage and
reengage the supply in rapid succession. Always remove a supply completely before
reinserting the same supply or a replacement supply. Rapid seating and unseating of
power supplies may result in false error conditions.
For information about removing and installing power supplies, see "How to Remove
a Power Supply" on page 153 and "How to Install a Power Supply" on page 155.
Sun Enterprise 250 Server Owner's Guide ♦ Revision A, June 1998
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