Northern Telecom DMS-100 Series Maintenance Manual page 53

Procedure 4-9
Disk drive replacement procedure - installing the replacement disk drive
Step Description
17 Once this procedure is complete, return to
the message procedure you left and
continue the activities.
Notes:
Note 1: If the disk system attains the PRIME mode, return the processor system to the PRIME mode. Make the processor
that is on the ONLY mode presently the PRIME processor. See Switch and Status Panel Operation for the procedure to
change processor modes.
Note 2: For 72- and 140-Mbyte disk drives, if the disk system does not become redundant, check the voltages to the disk
drive on the Disk II Crossover PCA. At connector J4, attach one lead of the meter to pin 2 or 4 for ground, attach the other
lead to either pin 1 or pin 3; read 8.5 V dc, +/- .25 V dc.
Note 3: If the voltages are proper, and the disk system does not achieve redundant operation, call for technical assistance.
(For the procedure, input command, to change disk modes, see the Craftperson Activity section of the procedure sheet for
the error message that was originally presented.)
Note 4: If the change of disk drives solves the problem, and local procedures indicate that the faulty disk drive is to be
returned, and it is a 72- or 140-Mbyte disk drive, be sure to ship its bad track map along with it.
Note 5: This procedure is recommended for most disk maintenance situations where the manufacturer's bad track map is
available on site. After initialization, this bad track data should be entered using the DISK DEFMAP command.
Note 6: This is the default selection for DPP systems equipped with 380-Mbyte disk drives, without the 56K polling feature
(no NT6M94AA mounted in slot A7 of the DPP processor chassis).
Note 7: This selection is not valid for DPP systems equipped with: 380-Mbyte disk drives with 56K polling feature, or
760-Mbyte disk drives, all instances; if an NT6M94AA PCA is mounted in slot A7 of the chassis, disk initialization is not
permitted.
Note 8: Proceed only if your DPP system is equipped with 72-Mbyte or 140-Mbyte disk drives.
Note 9: If your DPP system is equipped with 380-Mbyte disk drives, but no 56K polling, return to the message procedure you
were in and continue the activities listed.
Note 10: This procedure may take up to four hours, during which time the disk system is in a non-redundant mode. This
procedure should only be used if the manufacturer's bad track map is not available on site.
Note 11: If this procedure is chosen, and the bad track map is available, enter the bad track map upon completion of the
initialization process.
Note 12: This selection is not valid for DPP systems equipped with:
a. 380-Mbyte disk drives without 56K polling feature; defaults to the "short init" procedure, no "long init" permitted.
b. 380-Mbyte disk drives with the 56K polling feature; if an NT6M94AA PCA is mounted in slot A7 of the DPP processor
chassis, disk initialization is not permitted.
c. 760-Mbyte disk drives, all instances.
Note 13: If changing the A disk in a turbo DPP , set the options correctly on the drive or the system will crash.
Procedures 4-10 through 4-38 provide the procedures for the disk condition
and disk file error messages. Procedures 4-39 through Procedure 4-60
provide the procedures for disk drive hardware errors.
Notes
End
DPP Recovery and Routine Maintenance Guide BCS35 and up
Disk drive procedures 4-19
(continued)