Avaya Definity SI Maintenance Manual page 1170

Maintenance Object Repair Procedures
OUTLET
Figure 10-23. 645B Port Carrier Power Unit for DC-Powered Systems
Port Carrier Power Unit Replacement Procedures
The procedures for replacing a 644A or 645B carrier DC power unit are given
below.
If the port carrier power unit to be replaced is in a control carrier of a PPN system,
refer to the "Removing Power" and "Restoring Power" sections in Chapter 5,
"Routine Maintenance Procedures" before replacing the port carrier power unit. To
replace the port carrier power unit, follow the procedure below:
1. If this is a 645B power unit, set the power switch to OFF.
2. Unplug the power cord.
3. Move the locking slide on the power unit to the extreme left position, and
unlatch the locking lever.
4. Remove the power unit from the carrier.
5. Move the locking slide on the replacement power unit to the extreme left
position and open the locking lever.
6. Insert the power unit into the carrier until some resistance is felt.
10-384 Issue 4 May 2002
ON
OFF
STATUS
LEDS
RED
AMBER
LOCKING
LEVER
POWER
CORD
LOCKING
SLIDE
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