DEC Rackmount 7000 AXP Installation And Owner's Manual page 115

Perform the following procedure to remove the 3.3 Vdc/-5.2 Vdc regulator tray:
Before performing the following removal and replacement
procedures, switch off the circuit breakers on the back of the
XMI chassis and on the power controller.
1. Extend the XMI chassis for service (see Section 5.3.2).
2. Remove the top cover (see Section 5.3.3).
High voltage is present on the power supply connectors for about
30 seconds after the XMI circuit breaker is turned off.
3. Disconnect the power supply connectors from the tray (see Figure 5–21 and
Figure 5–22).
4. Remove the bottom cover (see Section 5.3.4).
5. Remove the -5.2 Vdc lead (white wire) from the stud on the backplane (see
Figure 5–25).
6. Remove the two 8-32 KEP nuts from the (-) bus bar on the 3.3 Vdc/-5.2 Vdc
regulator tray (see Figure 5–25).
7. Bend back the (-) bus bar.
8. Remove the two screws securing the 3.3 Vdc/-5.2 Vdc regulator tray in the
power supply assembly (see Figure 5–25).
Disconnect the ribbon cable from connector J6 before completely
removing the tray (see Figure 5–27).
9. Remove the 3.3 Vdc/-5.2 Vdc regulator tray from the power supply assembly.
To replace the 3.3 Vdc/-5.2 Vdc regulator tray, reverse steps 1 through 9.
Removal and Replacement
WARNING
WARNING
NOTE
Removal and Replacement 5–51