Check for the possible causes on the ODN and troubleshoot the faults accordingly.
Possible Cause |
Judgment Criterion |
Troubleshooting Method |
---|---|---|
The optical fiber connector is not clean.
NOTE:
An unclean optical fiber connector will cause excessive attenuation and abnormal reflection. |
|
Clean the optical fiber connector. For details about how to clean the connector, see Cleaning the Connector of an Optical Fiber. |
The optical fiber is bent excessively.
NOTE:
Optical signals attenuate seriously on an optical fiber with an excessively small bending radius. |
|
Route and bundle the optical fiber in a proper manner. |
The optical fiber is not firmly connected or different types of optical fiber connectors are interconnected.
NOTE:
If the optical fiber is not firmly connected or different types of optical fiber connectors are interconnected, the attenuation and reflection will be excessively large. |
|
NOTE:
In the scenario of the CATV service, it is recommended that you use APC connectors (green) only. |
The multi-mode optical fiber is used as the backbone or branch optical fiber.
NOTE:
If the multi-mode optical fiber is used as the backbone or branch optical fiber, the optical signal attenuates quickly and the return loss increases. |
|
Replace the multi-mode optical fiber with the single-mode optical fiber. |
The optical attenuation of the optical path is excessively small.
NOTE:
|
If either of the following two situations occurs, the optical attenuation of the optical path is excessively small.
|
Add an optical attenuator on the optical path between the OLT and ONU. |
The ODN is not properly planned.
NOTE:
|
The ODN does not meet the requirements of the ODN link plan or GPON Class B+.
|
Optimize the ODN to meet Huawei's ODN planning requirements and protocol requirements. |
The optical splitter is faulty or the connectors on the optical splitter are not clean. |
Measure the input and output optical power of the optical splitter by using the optical power meter. It is found that the actual attenuation exceeds the theoretical attenuation.
NOTE:
The faults in the optical splitter cannot be located by the OTDR because the OTDR cannot penetrate the optical splitter. |
Replace the faulty optical splitter or clean the connectors on the optical splitter. |
A backbone fiber break occurs. |
|
Reconnect the backbone optical fiber. |
A branch fiber break occurs. |
|
Reconnect the branch optical fiber. |