Hello,
Today I would like to share with you when ONU cannot go online due to fiber jumper error.
Symptom
Networking: The system adopts first-level splitting, with a splitting ratio of 1:16. The trunk fiber is 3.2km long, and the branch fiber is 600m long.
During deployment at a certain office, it was found that one of the ONUs failed to go online. The transmit optical power of the ONU was 1.27 dBm and the received optical power was -15.9 dBm. Neither power-off restart nor soft reset system can solve this problem.
Possible Causes
The optical power received by the ONU is greater than the overloaded optical power.
The optical power received by the ONU is less than the sensitivity value.
Abnormal attenuation on the ODN line.
The fiber is connected to the wrong port.
Steps
1. Measure the received optical power of the ONU as -15.9 dBm, and the received optical power is normal.
2. During remote query, it is found that the ONU is under another PON port, and it is inferred that the fiber jumper is wrong.
3. Confirmed on site and found that there is a fiber jumper error. As shown in Figure 1.
Figure 1 Optical fiber jumper
4. After the modification, the business returns to normal.
5. The system runs for a week, and the ONU goes online stably.
Suggestions
It is recommended to label different ports during construction and manage them separately to prevent wrong connection.
You are welcome to leave a message and exchange in the comment area. Thank you!
