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The Laser of the Raman board cannot be opened Highlighted

Latest reply: May 29, 2020 00:37:56 140 5 3 0

Hello, everyone! 

This post will tell you a case about the failure to turn on the laser on the Raman board due to poor fiber quality.

Problem Description:

The Laser of the Raman board cannot be opened. 

Handling Process

1. Validated the IPA configuration and it is ok. 

2. As a test we disabled the Auto OTDR detection function, after that the laser can be opened but the service does not go up. This means that the fiber quality does not meet SRAU requirements.

3. Use the OTDR to check the fiber quality and collect NE data. We analyzed the test data and found the following information: 

At a site, the data reported by the SRAU board in slot 15 is abnormal. The quality of the optical fiber connected to the SRAU board is poor. A large attenuation point exists at the 273m point, and the attenuation is 16.8dB.

The information reported by the SRAU board in slot 16 at the opposite site was abnormal. The reflection point was –29.17 dB at the 105-meter distance, which was large. 

Therefore, the fiber between sites has a big reflection on the near end in both directions which does not meet the Raman board. The fiber needs to be repaired.

4. After the fiber is repaired, the laser on the Raman board is turned on.

Root Cause:

The fiber between sites has a big reflection on the near end in both directions which does not meet the Raman board requirements.

Solution Description:

Repair the fiber between the two sites.

Usually, when we try to open the Raman laser on the SRAU board, the board will check the quality of the fiber. If the fiber doesn't perform well, it won't open the laser.

In addition, if we try to disable the OTDR function and open the laser on the Raman, The gain on the Raman board is going to below. The fiber end is at risk of being burned. 

Therefore, the best method is to check and repair the fiber between the two stations at first.

That's all, welcome everyone to leave a message and exchange in the comment area!

Thank you!

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MVE Created May 27, 2020 11:56:04 Helpful(0) Helpful(0)

Thanks for sharing!
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MVE Created May 27, 2020 12:00:14 Helpful(0) Helpful(0)

Well done
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MVE Created May 28, 2020 10:24:00 Helpful(0) Helpful(0)

Important solution to know, good job.
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Created May 29, 2020 00:37:44 Helpful(1) Helpful(1)

Very pleased
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Created May 29, 2020 00:37:56 Helpful(0) Helpful(0)

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