Entering Xbert; Testing Subscriber Lines - Nortel DMS-100 Series Maintenance Manual

7-22 Star Remote System manual maintenance
The ISOLATE command automatically runs tests to isolate a fault to a
particular set of cards. The number of cards in its card list can vary from one
to three depending on the individual test results.
The P-side ports of the host XPM or the Star Hub bus interface cards (BIC) can
be tested sequentially by one manual request.
Test XBERTBIC (bus interface cards)
For testing BICs, the XBERTBIC test path travels through the following cards:
•
•
•
•
XBERTBIC sets up the test path by attempting to establish a looparound of the
manually specified P-side port at an Star Hub BIC. With BIC, the test loop to
terminate must be manually specified. If the attempt is unsuccessful, a
response is displayed and the test is aborted. If the NT6X54 looparound is
successfully allocated, the test is run.

Entering XBERT

The XBERT level can be entered at any level of the MAP terminal. The user
enters one of the following commands:
•
•
By entering the command XBERT N <<node#>>, the user is entering XBERT
through the PMs node-assignment number. Node-assignment numbers may be
found in table NNASST or by posting the PM to be tested at the PM MAP
display level using the QUERYPM command.

Testing subscriber lines

Line circuits, subscriber loops, and stations are tested under the lines
maintenance (LNS) subsystem. Line circuits and subscriber loops are tested
manually and automatically in this subsystem.
Line testing helps determine if a line circuit, loop, or line circuit and loop
combination are functioning properly. If the line proves faulty, line tests also
determine if the fault lies in the line circuit or the attached loop. When a fault
is in the loop, it is usually referred to another department (for example, plant
maintenance). When the fault is in the line circuit, the line card is replaced and
the line is retested to verify the fault is cleared.
297-8353-550 Standard 05.01 March 2001
messaging card (NTMX76AB)
timeswitch card (NT6X44)
DS-1 interface card (NT6X50)
BIC (NT6X54)
XBERT <<PM>> <<PM#>>
XBERT N <<node#>>