Chapter 5, Part replacement, 1 general rules – Nortel Networks DCT1900 User Manual

Page 377: 2 replacing a system board, 3 replacing the cpu, 5part replacement

Technical Product Manual - DCT1900

Maintenance, Part Replacement

Maint-DCT1900/R8/mw

5-1

HAPTER

Part Replacement

5.1

General Rules

Always protect yourself with a properly connected ESD wrist–strap before touching any board.

Pack replaced boards immediately in ESD safe material. Use the packing materials from the
replacement board.

When sending a board in for repair, always include a printout of the corresponding fault report
from the service table. If possible also include prints of info, fault and reset tables. Return the
board together with a completed "RMA Form" (ask your service manager or distributor).

Please observe that some CSMW software commands used in this chapter require a
distributor privilege level.

5.2

Replacing a System Board

All system boards, except the CPU, use the same board replacement procedure. There is no need
to switch off the system when replacing boards, except for the CPU.

Before replacing a faulty system board, the board must be set free from traffic. This is done by the
Replace command. No new traffic is accepted, while existing calls can be terminated normally.
These busy circuits will be blocked immediately after the call has ended. After the message "you
can now replace the board," the board is set free.

Procedure
1.

Select Board in Radio Exchange window by left clicking on the listed board.

Right click and select Replace or choose Board-Replace from the menu bar.

Choose if you want to wait for calls to terminate before execution.

Wait until the message "you can now replace the board" appears on the PC screen

Disconnect cables from board (mark their position!).

Remove the board.

Insert the new board in exactly the same position.

Re–connect cables.

Put the defective board in ESD bag and box.

After insertion, the board will start its board–power–on test. After the test is finished, the board will
be taken into service automatically.

5.3

Replacing the CPU

If possible, back–up the contents of the EEPROM to the PC by selecting File-System Backup.

The most "elegant" procedure is to make the system free of traffic before replacing the CPU board.
This can be done by executing the System Manager–Control–Replace board command for all
SPU and SLU boards starting at the board with the highest board number. When the last board
"can be replaced," exit the CSMW software program. Also, let the users know that the system will
be out-of-service before removing the CPU.