363-206-305 Trouble Clearing:
TAP-112
Issue 3, June 2000 Page 13 of 16
DDM-2000 F
IBER
R
EACH
W
IDEBAND
S
HELF
22. !
CAUTION:
Removal of an unprotected circuit pack may cause service interruption.
NOTE:
The –48V power feeders/fuses on the User Panel supply power to
DC-to-DC converters on the OLIU, DS1, DS1PM, T1EXT, DS3 and
SYSCTL circuit packs. It is unlikely that a circuit pack failure would cause
only one feeder fuse to blow. The more probable cause of failure of only
one feeder fuse would be a short of the backplane feeder path or a
problem with a circuit pack shelf connector. After a thorough inspection
of the backplane, if no trouble is found, the circuit packs can be removed
one at a time to try and isolate the trouble.
Remove
one
of each pair of circuit packs listed in the above note and replace
blown –48V fuse. If fuse does not blow again, reinstall all removed circuit
packs one at a time, beginning with the SYSCTL. Replace any circuit pack that
causes the fuse to blow (DLP-523). If fuse blows again with one of each pair
of circuit packs removed, reinstall removed circuit packs and repeat the
procedure for the remaining circuit packs (except DS1s). If fuse blows after all
circuit packs have been removed, trouble is in the backplane.
23. STOP. YOU HAVE COMPLETED THIS PROCEDURE.
24.
NOTE:
Alarm may be caused by circuit packs inserted into the wrong slots.
Are circuit packs installed in the correct slots (rtrv-eqpt)?
If YES, proceed to Step 27.
If NO, continue with Step 25.
25. Remove circuit packs from wrong slots, check option switches (DLP-513) and
reinstall circuit packs into the correct slots.
26. STOP. YOU HAVE COMPLETED THIS PROCEDURE.
27.
!
CAUTION:
When removing circuit packs ensure that protection switching is
available. Also, remove the circuit pack without the lighted
ACTIVE
LED
first.
Check switch settings for correct settings. If the circuit pack has been replaced,
check if settings are the same as they were before the circuit pack was
replaced. Also check if the switches are set the same as the companion circuit
pack.
Reference: DLP-513
To Next Page
Loading...