Service manual

GS160/320 Component Removal and Replacement 4-15
4.3.4 Getting a FRU into the AC Off State
FRUs that require AC Off are system backplanes, clock modules, the
hierarchical switch backplane and power manager, and a power
subrack. The PCI is a special case where the system can be running,
but all power is removed from the PCI.
Dual-Output Clock, H-switch Clock, Distribution Board, H-switch, CSB
Module, OCP, and HPM
1. Shut down the operating system(s).
2. Trip the master circuit breaker on all AC input boxes. AC is now removed.
System Box
1. If the system is not partitioned, shut down the operating system and remove
AC by powering off the system and tripping the main circuit breakers on the
AC input boxes. Return to the system box removal procedure (Section
4.5.8).
2. If the system is partitioned, shut down all instances of the operating system
in the QBBs in the target system box.
4. To power off the partition(s) in the target system box use the SRM power
off command from the console connected to the hard partition that contains
the FRU.
5. Trip the color-coded circuit breakers on the AC input box powering the
target color-coded system box. AC is now removed from the target system
box while the rest of the system remains powered on.
6. See Section 4.5.8.
PCI Box
1. If the operating system supports hot-swap I/O, remove the I/O resources
contained in the target PCI from the operating system. Otherwise, shut
down the operating system(s) running in the hard partition or system.
2. Power down the hard partition or system.
3. Pull the plugs from the target PCI box’s power supplies.
4. Remove the FRU.