Xpm Bit Error Ratio Test - Nortel DMS-100 Series Maintenance Manual

10-6 Trouble isolation and correction

XPM bit error ratio test

The host XPM performs the XPM bit error ratio test (XBERT) for the OPM
subsystem. The XBERT is a diagnostic test that does the following:
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The XBERT detects bit errors in the transmission of high-speed data in the
cards of the host XPM. These cards can be a line group controller (LGC), line
trunk controller (LTC), or remote cluster controller (RCC), and cards in the
OPM. The XBERT tests are provided with feature package NTX885AA.
These tests also require the NT6X99AA IBERT line card supplied in the LCM
of the OPM.
Note: To use XBERT, the XPM must have an NT6X69AB message
protocol card or an NT6X69AA message protocol card. The XPM must
have an NT6X69AB message protocol card or an NT6X69AA message
protocol card with an NT6X79 tone card.
Test conditions
For accurate fault detection, XBERT tests run on an active in-service XPM
unit. The XBERT tests also can run on an out-of-service unit. A minimum of
one unit of the OPM must be in-service.
Note: The user must not use the XBERT as a tool that provides accurate bit
error ratio evaluation. The XBERT test procedure does not use the CCITT
standard test patterns. The XBERT uses XPM tone PCM to provide the
64-kbps test bit stream.
Test types
The XBERT runs two tests, with the use of the Initiate (I) command. The tests
involve the OPM. The test names and the associated cards of the test names
appear in the following table.
Table 10-2 XBERT tests
Test name
XBERTDCC
XBERTBIC
297-8361-550 Standard 04.01 September 2000
detects and measures pulse code modulation (PCM) bit errors that occur in
XPM and OPM cards
commissions DS-1 and PCM-30 links and trunks which are looped back
DS-1 and PCM-30 without the use of a remote node
Related cards
NT6X44, NT6X50, NT6X69, NT6X52, NT6X73
NT6X44, NT6X50, NT6X69, NT6X52, NT6X54,
NT6X73