Nortel SONET AccessNode User Manual page 120

7-18 Replacing modules in a common-equipment shelf
Procedure 7-8 (continued)
Replacing an NT4K53 maintenance interface card
Step
3
4
5
6
7
8
AccessNode P0904244 Issue 1.0
Action
Investigate the condition that caused the DS1 protection switch to occur. Do
not continue with this procedure until the DS1 protection switch is cleared.
From the Network Element Status screen, display the maintenance interface
equipment screen:
eq mic↵
The MIC equipment screen appears.
To prevent alarms from being raised when the circuit pack is removed, take
the maintenance interface card out of service:
chgstate oos↵
y↵
The state of the MIC changes to out-of-service (OOS).
Remove the ABM shelf cover as shown in Chapter 3, "Removing covers and
grilles."
CAUTION
Loss of functionality upon MIC removal
Removing the maintenance interface card (MIC)
causes the following functions to be inoperative:
• loss of DS1 protection switching.
(For details, see caution box before step 1.)
• Local craft access (orderwire)
• serial and parallel telemetry scan points
• common-equipment LEDs clock monitoring clock
• DTE modem
• external alarm drivers
Pull the circuit pack ejector latches to remove the maintenance interface
circuit pack from the shelf, as shown in Figure 7-4.
Wait at least 5 seconds before installing the replacement card. Insert a
replacement maintenance interface card in the shelf. Gently push the
replacement circuit pack in until the ejector latches come in contact with the
front of the shelf. Then push the latches in toward the circuit pack to engage
the circuit pack with the backplane connector.
—continued—