Nortel SONET AccessNode Manual page 44

2-26 DS3 tests, STS-1 tests, and optical in-bay tests
Procedure 2-3 (continued)
Testing optical protection switching
Step
Testing automatic switching due to loss of optical signal
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22
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AccessNode Vol 3B 323-3001-221 Issue 2.0
Action
To cause an automatic switch of the optical facility, remove the optical test
cord from the transmit (Out) connector of G2 OC-3/OC-12, as shown in
the figure in step 15.
For OC-12 VTBM, the OC-12 Protection screen displays an (*R) in the Auto
field of G2. G2 active LED is turned off.
For other OC-3/OC-12, the OC-3/OC-12 Protection screen displays an
asterisk (*) in the AutoSw field of G2. On the G2 OC-3/OC-12 circuit pack, the
yellow loss-of-signal (LOS) LED turns on. The green (Active) LED on the G1
OC-3/OC-12 circuit pack indicates that circuit pack is now active.
On the DS3/STS-1 test set, press the Start/Stop button twice to reset the
error count to zero.
The DS3/STS-1 test set indicates in process and displays 0 bit error.
To verify DS3 or STS-1 continuity, press the Single Bit Error Inject button
three times on the DS3/STS-1 test set.
The DS3/STS-1 test set displays 3 bit errors received.
Reconnect the optical test cord to the transmit (Out) connector of the G2
OC-3/OC-12 circuit pack.
For OC-12 VTBM, the OC-12 Protection screen displays a (WR) in the Auto
field of G2. Once the wait-to-restore period expires, the G2 active LED is lit.
For other OC-3/OC-12, the yellow loss-of-signal (LOS) LED goes off on the
G2 circuit pack. The screen displays a dot (.) in the AutoSw field for the G2
circuit pack.
—continued—