Lines Maintenance; Automatic Line Testing - Nortel DMS-100 Series Maintenance Manual

10-8 Trouble isolation and correction
When the user enters the command XBERT N <<node#>>, the user enters
XBERT through the PMs node-assignment number. Table NNASST contains
node-assignment numbers. The user can locate node-assignment numbers
with the QUERYPM command to post the PM. Test at the PM MAP display
level.

Lines maintenance

Tests occur under the the lines maintenance (LNS) subsystem for line circuits,
subscriber loops, and stations. Tests occur on line circuits and subscriber loops
manually and automatically in this subsystem.
Line tests help determine if a line circuit, loop, or line circuit and loop group
operate correctly. If the line is defective, line tests determine if the fault occurs
in the line circuit or the attached loop. When a fault is in the loop, another
department, like plant maintenance, handles this fault. When the fault is in the
line circuit, the system replaces the line card. Tests for the line occur again to
check that the fault cleared.

Automatic line testing

Automatic line tests (ALT) occur on line circuits and loops on a scheduled
basis. The ALT occur without switch operator involvement other than for the
first scheduling. The ALT must occur when a line indicates a fault.
The following figure shows the commands available at the sublevels of the
LNS subsystem.
297-8361-550 Standard 04.01 September 2000