Verilink 1558D (34-00255) Product Manual - Manual (Page 15)

Installation 2-7 1558D APS CSU/DSU
• The Path Status, Alarm B (red) LED may be ON or OFF
depending on the alarm timer setting (0 to 900 seconds)
configured in the 1558D.
5. The 1558D unit is now looped back to the V.35 DTE port
and the BERT test set should be running in sync and
error free. If not, verify that the test set speed and clock-
ing settings are set to work with the speed and clocking
options configured for the 1558D.
Standalone pre-service testing verifies the operational
integrity of the 1558D using both the A and B path circuitry.
If either Path A or Path B fails, but not both, and the options
have been verified, contact the TxPORT Customer Service
for additional assistance.
End-to-End Pre-Service Testing
The following paragraphs describe pre-service APS testing
of the 1558D when it is initially connected to the T1 facili-
ties (Path A and Path B) and is configured with another
1558D APS at the far-end.
After completing the stand-alone pre-service test proce-
dures, the 1558D is ready to be connected to the Path A and
Path B T1 facilities for verification of end-to-end opera-
tion. These test procedures will verify the following:
• End-to-End Performance of Path A
• End-to-End Performance of Path B
• Ability to generate remote V.54 loop of 1558D port
The following steps assume that there is a near end unit and
a far-end unit and a technician with a BERT test is at both
locations (near and far).
1. Attach the Path A and Path B T1 facilities to the respec-
tive NET A and NET B modular jacks at the rear of the
unit (both near and far locations).
2. At both locations attach the data BERT test sets to the
1558D DTE port making sure that the speed and clock-
ing settings match those configured in the 1558D unit.
3. Operate the Service Select switch on the 1558D to the
Path A position at both the near and far 1558D units.
This forces both units to use Path A as the receive signal
source. Once this is done, both test sets should indicate
pattern sync at both the near and far locations. Run test
for a minimum of 15 minutes. The test results should be
error free at both ends. If errors are detected, repeat test
for another 15 minutes. If errors are still detected, a prob-
lem exists in the T1 facility. Refer problem to appropriate
channels for resolution.
4. Operate the Service Select switch on the 1558D unit to
the Path B position at both the near and far 1558D units.
This forces both units to use Path B as the receive signal
source. Run test for a minimum of 15 minutes. The test
should be error free at both ends. If errors are detected,
repeat test for another 15 minutes. If errors are still
detected, a problem exists in the T1 facility. Refer prob-
lem to appropriate channels for resolution.
After completing the end-to-end BERT testing of both Path
A and Path B facilities, verify that the remote V.54 loop
operates properly by performing the following steps.
1. To verify that the loop operates, simply move the DTE
manual loop switch from the AUTO to the RL (remote
loop position). The unit responds by:
2. TEST LED indicator turns On (amber) and the 1558D
internally generates a V.54 loop code to the far-end for
≥
five seconds.
3. After approximately five seconds, the TEST LED indica-
tor will change from amber to green if the V.54 loop
operated at the far-end. If the loop did not operate, the
TEST LED will turn from amber to red which indicates
that the far-end unit did not respond to the requested V.54
DTE loop.
The remote V.54 loop will remain active until the DTE man-
ual loop switch is moved from the RL position back to the
AUTO position. When this is done, the 1558D will generate
an UNLOOP command to the far unit. After approximately
≤
five seconds the front panel TEST LED indicator will
change from green to off.
This completes the end-to-end operational check for the
1558D. Remove all test equipment and verify that both units
are attached to the T1 facilities (NET A and B) and verify
that the DTE high speed data application is attached. After
performing these checks, the 1558D unit is now ready to
fully support proactive automatic protection switching and
performance monitoring.