AT&T 3.0 manual Replacing the Power Supply, Power down the system

Power Supply Problems

Replacing the Power Supply

WARNING:

Beware of hazardous voltages; whenever the carrier connections are exposed, use extreme caution; do not touch them directly or with any type of tool. Follow ail procedures carefully.

To remove the power supply module, follow the steps below.

1If possible, backup system programming on a memory card (Release 3.0 only) or floppy disk.

See System Programming and Maintenance (SPM) for information about backing up to a floppy. For information about backing up to a PCMCIA memory card, see Appendix D, “Backing Up with a Memory Card.” If the basic carrier’s power supply fails, you cannot back up system programming.

2 Power down the system.

aTurn off the power supply in the basic carrier.

bTurn off the power supply in each expansion carrier.

cUnplug the auxiliary power unit, if present, from the AC outlet.

3 Unplug the system from the AC outlet.

4 Remove the power supply.

aUnplug the AC power cord from the power supply.

bRemove the ground wire attached to the grounding screw on the front of the power supply module.

cRemove the two ferrite cores, if present, from around the AC power cord and ground wire.

dRemove the power supply module.

4-10Control Unit Problems