Specifications

X723-300151 6-20 Issue 2
6.3 Network Problems
All networks will occasionally show problems. These may be indicated by
one or more of the following:
a) Alarm relays operating.
b) Alarm indicators lighting.
c) Alarm messages displayed if fault logging is on.
d) Communication problems through the network.
Problems can be caused by any one or more of the following:
a) Power loss at a node.
b) PCM transmission problems.
c) Synchronisation problems.
d) Incorrect equipment configurations.
e) Equipment faults.
The 3200 contains comprehensive fault tracing facilities to enable
operators to determine, and rectify, the cause of any network faults.
When a fault occurs, or clears, a message is added to the fault message
store, and displayed if fault logging is on. This can be used for detecting
faults as they occur and is useful for checking intermittent faults. This
facility must be used with caution as the fault message store has a limited
capacity. If a main fault occurs, say primary sync source loss, this could
cause frequent PCM frame slips to occur. The messages for these would
rapidly fill and overflow the message store. Listing the store would then
only list frame slips. The cause of the problem, primary sync loss, would
not be listed. The most important fault tracing facility is the 'Fault'-
'Active' sub-menu, on the multiplexer and smart channel cards. This
allows listing of the presently active faults, or optionally active faults
separated into several fault groups. In the above example the primary
clock loss would be listed under the Sync fault group.
Another facility which is useful during fault checking is the 'Maintenance'-
'Current' command. This allows listing of the current sync source,
configuration and other data.