Nortel DMS 100 Series Maintenance Manual page 46

2-30 Maintenance overview
The LLFA, LLMA, RFAI, and RMAI are the PCM30 carrier alarms. The
LLFA and LLMA are associated with signals from the lines to the RSC-M.
The type of PCM30 alarms the system generates determine if these alarms are
associated with these signals. The RFAI and RMAI associate with signals
from the RSC-M to the lines. Steady-state frame loss for a specified duration
in table CARRMTC generates LLFA and LLMA alarms. When the system
regains the frame, the system clears these alarms for a specified duration.
Table CARRMTC provides the value for this duration.
Isolated or intermittent faults like frame losses or slips accumulate. When the
faults reach the ML, the system updates a field marked ML on the MAP
display. This update serves as a warning to operating company personnel that
faults can occur on the carrier.
The system flags a carrier temporarily system busy (SysB-T) or permanently
system busy (SysB-P). This flagging depends on the number of times the
system returns the carrier to service.
The system sets the carrier to SysB-T if a steady state alarm occurs for a
carrier. A steady state alarm is an alarm that did not clear. The system sets the
carrier to SysB-if the carrier exceeds the OOS for frame losses or slips.
The DMS switch places a carrier system busy (SysB) when the following
alarms occur:
•
•
•
•
•
•
The DMS switch can RTS the carrier when the system clears the alarm (frame
regained).
The user can enter a limit on the number of times a carrier is RTS. This entry
makes sure a carrier does not bounce indefinitely between SysB and INSV
states. The default for the consecutive number of times the system can RTS
the carrier is 255.
A carrier remains SysB-T until you RTS the carrier correctly. The RTS occurs
when the tests of the RTS sequence pass. Successful test indicates that no
faults remain on the carrier. The system sets the carrier to SysB-T when the
carrier audit does not find alarms in the carrier.
297-8223-550 Standard 04.02 November 2000
LLFA
LLMA
RFAI
RMAI
AIS
BER