ADTRAN 1187715G1, Руководство по установке и обслуживанию

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Troubleshooting
61187715G1-5B 47
Upstream Signal Level Verification
A valid optical power level delivered by the ONT must be received by the OLT on the GPON
to assure proper ONT ranging and operation. The laser output of the ONT is burst mode at
1310 nm that is controlled in the upstream direction by grants given by the OLT.
The individual optical power level that should be present at the optical bulkhead that is
located on the ONT is listed in Table 10 .
To verify the correct upstream optical signal level is present, complete the following steps:
1. Ensure all connectors are clean and dry. Refer to the “Cleaning and Inspection of Compo ‐
nents” on page 44 for details.
2. Setup and calibrate an OPM or OLTS that can be placed inline on the optical fiber and is
capable of performing wavelength filtering in order to obtain individual wavelength
optical power level readings.
3. Connect the test equipment to the optical fiber drop cable and the optical bulkhead on
the ONT using a test jumper as shown in Figure 27 on page 47.
Figure 27. Upstream Test Configuration
4. Verify the test equipment measurement results are within the optical signal level range
described in Table 10 above.
5. If the measurement results are within range, perform a verification of the provisioning of
the ONT at the OLT and verify that the proper upstream signal level is being received by
the OLT.
6. If the measurement results are not within range, perform a verification of the
provisioning of the ONT at the OLT. If after verifying the provisioning the problem still
exists, replace the ONT.
Table 10. Upstream Power Levels
Optical Wavelength Minimum Power Level Maximum Power Level
1310 nm
1600 to 1620 nm
0 dBm
1.0 dBm minimum
+5 dBm
+3 dBm
1310 nm
1490 nm
Test jumper Drop cable
OPM
or
OLTS ONT
1550 nm
1610 nm Upstream