Compaq EK-SMCPO-UG. C01 manual Replacing the EMU Board, Tools required

Maintenance 3-11

Replacing the EMU Board

WARNING: Only qualified service personnel should replace the EMU. Dangerous voltages are exposed when the pedestal side panel is removed. Always power off the pedestal and remove the power cords before replacing the EMU.

Tools required:

■Flat-blade or 3/16 in(5 mm) hex-head screwdriver

■# 10 TORX-head screwdriver

Perform the following procedure to replace the EMU Board:

1. Quiesce the host bus by shutting down the host system.

CAUTION: To allow the UPS to supply power while the cache is being flushed to disk, do not unplug the base pedestal from the UPS.

2.Unplug the base pedestal power cord from the wall outlet.

3.Unplug the UPS power cord from the wall outlet. The UPS will now signal the controller to flush the cache.

4.Wait until the UPS shuts down completely (this may take several minutes).

5.Power off the base pedestal and plug the UPS power cord into the wall outlet.

6.Remove the pedestal door.

7.Remove the left side cover from the pedestal (see “Reconfiguring the SCSI Bus”).

8.Record the orientation of the color traces on the two ribbon cables connected at the rear of the EMU board and disconnects the cables.

9.Remove the hex standoffs from the UPS and external fault connectors on the rear panel using a hex-head or a flat-blade screwdriver (Figure 3–7).

10.Remove the board from the pedestal.