Backplane - DEC 4000 AXP Service Manual

5.4 Backplane

Refer to Figures 5–10 and 5–11.
Part Number
70–28747–01
17–03340–01
17–03341–01
Removal and Replacement Tips
To remove the backplane:
1. Unseat all modules (CPU, memory, I/O, and power supply modules) from the
rear backplane.
2. Unseat and remove the Vterm module and all storage devices from the
storage backplane.
3. Remove SCSI out connector and disconnect its cable from the storage
backplane.
4. Remove outer shell (Figure 5–10).
5. Remove screws (Figure 5–11) and with the aid of an assistant, slide the front
chassis forward enough to remove the backplane.
Before removing the backplane, inspect the backplane cable assemblies. If the
cables are damaged or improperly connected, replace the cables and not the
backplane.
Lifting the front chassis requires two people.
To replace the backplane:
1. Secure the backplane with the two screws at the center.
2. Make sure the backplane is properly aligned by securing the front chassis to
the rear chassis using the four screws at the top.
3. Replace remaining screws.
5–20 Repairing the System
Name
Backplane assembly
Cable assembly, 100-conductor backplane-to-backplane (2)
Cable assembly, 40-conductor, backplane-to-backplane
Warning