Nortel Meridian SL-1 Supplementary Manual page 14

2- 6 Upgrading LE, A, M, MS to Option 21
Shelf upgrades to Meridian 1 553-3001-253
• Connect connector D on the QCAD349A alarm cable to connector
D on the end of the QSD81 common equipment shelf (Figure 2-
2).
15 Disconnect all previously tagged cables from the connectors on the
QPC45, QPC139 and QPC50 circuit packs and connect to their
assigned circuit packs on the QSD81 CE shelf.
16 Disconnect the power connector (connector P2 on the cabinet power
distribution harness) from the shelf containing the tape unit.
17 Set circuit breakers CPU 1, NET 0 and NET 1 on the QBL10 power
distribution in the QCA23 cabinet to OFF.
18 Disconnect power connectors and any remaining cables from the end
of the following shelves (Figure 2-1):
• the tape unit shelf in position 2.
• the QSD12 CPU/Memory shelf in position 3.
• the QSD13 Network shelf 1 in position 4.
• the QSD13 Network shelf 0 in position 6, if the shelf is not
required for other services such as DTI.
19 Remove any remaining cables that are connected to the front of circuit
packs on the shelves being removed and remove the shelves.
20 Perform this step only if the QSD13 Network shelf 0 in position 6 has
been removed.
• Disconnect the power connector from the end of the QUD4
cooling unit in position 6 and remove the cooling unit. Insert a
P0625843 shorting clip in terminals 1 and 2 of the power
connector disconnected from the QUD4 cooling unit (Figure 2-4).
Note: The P0625843 shorting clip is installed to prevent an alarm
indication because of the missing cooling unit.
• Unseat diskettes from the NT8D68AA Floppy Disk drive.
21 In the QBL10 power distribution box:
• Set CAB INP breaker to ON.