Nortel DMS-100 Series Maintenance Manual page 381

minor
power/miscellaneous
shelf.
These alarms appear as PM128 log reports at the MAP terminal. In addition
to the description provided in the following paragraphs, information and
instructions for actions are provided in the alarm description table in this
document.
Major alarm
A major alarm indicates a fault occurred that affects service to subscribers.
If a major alarm occurs without a shelf alarm, the RCS is system busied. If a
major alarm occurs with a shelf alarm, the RCS is placed in ISTb.
When system busied, a CM audit attempts to RTS the RCS. This audit runs
in 10 min intervals. If this audit correctly returns the RCS to service or if
the RCS is manually returned to service, the alarm clears.
When the RCS is ISTb, operating company personnel must enter the
command string
>QUERYPM FLT
Normally, it is a defective line interface unit (LIU) or transmit receive unit
(TRU) card.
An example of a failure that causes a major alarm and a shelf alarm is the
failure of the derived data link (DDL) looping test. The DDL tests
messaging capability between the SMS and RCS. Another example occurs
when the SMS detects a failure of a DS-1 link for a shelf local carrier group
alarm (LCGA).
Minor alarm
A minor alarm indicates a fault occurred that does not affect subscribers.
This alarm means that the RCS is placed in ISTb.
Disabling protection switching is an event of a non-fault condition that
causes a minor alarm.
Failure of the pulse code modulation (PCM) looping test used to check
transmission over an assigned DS-1 channel in Mode II is an example of a
fault condition. This fault condition causes a minor alarm.
Power/miscellaneous alarm
A power/miscellaneous alarm indicates a power failure or an optional
miscellaneous fault. The RCS is set to ISTb for this alarm.
to determine the cause of the alarm.
DMS-100 Family SMS Maintenance Manual XPM10 and up
Trouble isolation and correction 9-17