
FRP 3: Power Supply Replacement
AC Repair and Adjustment Procedures
22
Cray Research/Silicon Graphics Proprietary
HMM-168-A
Power Supply Removal
1.
Open the front cabinet door.
2.
Locate the defective power supply and ensure that the associated module
is logically removed from the system. (The module may remain
physically installed in the system.)
3.
Open the power supply circuit breaker for the defective power supply
(CB2 through CB7).
The green AC power LED on the power supply and the power LED on the
module should be off.
4.
Remove the power cord:
a. Remove the lower connection from the circuit breaker box. (The
mechanical interlock will rotate and close the rail damper to restrict air
flow through the power supply.)
b. Remove the upper power cord connection, and set the cord aside.
5.
Use a small flatblade screwdriver to disconnect the control connector
from the defective power supply.
6.
Use a 2-mm hex wrench to loosen the retaining screw (setscrew) at the
bottom of the power supply handle. It is not necessary to remove it from
the power supply handle.
7.
Remove the power supply:
a. Grasp the power supply handle and pull with firm, even pressure.
(When the handle pulls free of the top mechanical interlock, the
interlock will rotate and close the top rail damper. Refer to
. If
the top interlock does not rotate, manually rotate the interlock 90˚
counterclockwise to close the top rail damper.)
b. When the power supply is halfway out of the cabinet, place one hand
on the bottom of the power supply.
c. Pull the power supply out of the cabinet.