System Overview
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When AC is applied to the system, Vaux (auxiliary voltage) is asserted and is sensed
on the server feature module. If the On-Off Button is On, and RCM OK and Interlock
OK are asserted, the OCP asserts DC_ENABLE_L starting the power supplies. If
there is a hard fault on power-up, the power supplies shut down immediately;
otherwise, the power system powers up and remains up until the system is shut off or
the server feature module senses a fault. If a power fault is sensed, the signal
SHUTDOWN is asserted after a 30 second delay. Cycling the On-Off button can
restore the power. If the system powers up and shuts off in approximately 30 seconds,
the server feature module has sensed a fault and a fan (system or CPU) is likely
broken.
