Nortel SONET AccessNode Manual page 60

2-42 DS3 tests, STS-1 tests, and optical in-bay tests
Procedure 2-4 (continued)
Testing DS3 or STS-1 protection switching
Step
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AccessNode Vol 3B 323-3001-221 Issue 2.0
Action
Press the Start/Stop button on the test set connected to the high priority unit
(G1) twice to reset the error count to zero.
The DS3/STS-1 test set indicates in process and displays 0 bit error.
To verify that DS3 or STS-1 continuity exists and that the DS3s/STS-1s
normally handled by the G1 (high-priority) mapper are rerouted to the
protection mapper, press the single bit error inject button three times.
The DS3/STS-1 test set indicates in process and indicates 3 bit errors
received.
Reinsert the G1 (high-priority) DS3/STS mapper or STS-1 interface card into
its backplane connector.
DS3 or STS-1 traffic is restored to the high-priority mapper. The protection
mapper resumes handling the low-priority DS3s/STS-1s from mapper G2.
Alarms clear.
Press the Start/Stop button on the test set connected to the high priority unit
(G1) twice to reset the error count to zero.
The DS3/STS-1 test set indicates in process and displays 0 bit error.
To verify that DS3 or STS-1 continuity exists and that the protection mapper
has resumed handling the DS3s/STS-1s from the G1 (high-priority) mapper,
press the Single Bit Error Inject button three times.
The DS3/STS-1 test set indicates in process and indicates 3 bit errors
received.
Reinsert the G2 (low-priority) mapper into its backplane connector.
The screen displays WTR (wait to restore) for five minutes, and then a dot (.),
in the AutoSw field. When the G2 mapper goes back into service after the
wait-to-restore period, it resumes handling the low-priority DS3s/STS-1s.
Alarms clear.
Press the Start/Stop button on the test set connected to the low priority unit
(G2) twice to reset the error count to zero.
The DS3/STS-1 test set indicates in process and displays 0 bit error.
To verify that DS3 or STS-1 continuity exists and that the G2 (low-priority)
mapper has resumed handling the low-priority DS3s/STS-1s, press the single
bit error inject button three times.
The DS3/STS-1 test set indicates in process and indicates 3 bit errors
received.
—continued—