Method used to handle the NO_BD_PARA alarm on a CRPC Raman amplifier board

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Question:
A CRPC board on an OSN 6800 NE reports a NO_BD_PARA alarm, and the alarm parameter is 0x01 0x00 0x01.
Analysis:
1. The board software is lost.
2. Board data configurations are incorrect.
3. The board hardware is faulty.
Root cause:
None
Answer:
1. Query the board software information. The board software information can be normally queried, and alarm information indicates that the board software is not lost.
2. Check whether board settings are correct. On the NMS, select the CRPC board and choose Configuration > WDM Interface in the navigation tree. Select By Board/Port (Channel) and click the Advanced Attributes tab. In Fixed Pump Optical Power (dBm), query the pump laser optical power which is -60 dBm. Set it to 24 dBm. Then the NO_BD_PARA alarm is cleared.
Suggestions and conclusion:
1. The CRPC board is a Raman amplifier board. The Raman pump optical power is disabled before delivery to avoid personal injury at deployment. Therefore, the queried value is -60 dBm. This value does not meet board requirements, and therefore the NO_BD_PARA alarm is reported.
2. The CRPC board (backward Raman amplifier board) requires that the gain of each wavelength should exceed 10 dB. During deployment commissioning, set the initial pump power value of the board to the recommended value as follows:
For a G.652 or G.655 fiber, you are advised to set the optical power to 24 dBm for the first and second pump lasers.
For a G.653 fiber, you are advised to set the optical power to 23 dBm for the first pump laser and to 22.5 dBm for the second pump laser.

Other related questions:
Precautions for replacing a Raman amplifier board
You should shut down the pump laser of the Raman amplifier board before removing the fiber from the Raman amplifier board, avoiding human body injuries.

Whether the CRPC board can amplify the optical power of the SC1/SC2 board
The CRPC board cannot amplify the optical power of the SC1 or SC2 board.

Method used to handle the POWER_FAIL alarm on the TN52SCC board
Check the settings of the battery jumper on the TN52SCC board. If the board is not powered by batteries, configure the board power supply status to ensure that the board is powered by batteries. For details how to set the battery jumper, see the Hardware Description. If the POWER_FAIL alarm is reported by the TN52SCC board, the battery of the board is abnormal (the value of alarm parameter 1 is 0x05). 1. On the NMS, back up the NE configuration data to the database in the flash memory of the TN52SCC board. 2. Check whether the jumper cap is correctly placed over the battery jumper. If it is, check the jumper setting of the battery on the board. If the setting disables the battery from providing power, modify the setting to ensure the SCC board is powered using the battery. 3. If the alarm persists, use a multimeter to measure the battery voltage. If the voltage is lower than 3 V, the battery is faulty. When this occurs, replace the TN52SCC board.

Method used to handle the TEMP_OVER alarm reported by the CXP board
1. Check whether a fan stops running on the fan board. If yes, remove and insert the fan board. If no, go to the next step. 2. Clean the air filter.

Questions about using Raman boards
Question: Issues are likely to occur on Raman boards during deployment or maintenance, most of which are caused by customer lines and can be resolved by cleaning the optical path, replacing the ODF connectors, or fiber splicing. The following shows some examples of the questions of the customers and Huawei engineers: 1. Why is the maximum gain different before and after the RAU replacement for the same link? 2. Under certain conditions, the customer lines cannot be rectified in a short time. The actual maximum gain of the Raman board is only 5 dB or 6 dB (stable) whereas the system stability is excellent. Will the system run stably in this condition for a long time? Are there any pigtail burning risks? 3. The Raman lasers were closed before line operations, but the pigtails of some sites are still burned. Why cannot the mechanisms such as IPA or return loss detection avoid fiber burning? Answer: 1. Why is the maximum gain different before and after the RAU replacement for the same link? Answer: The actual gain of the RAU is closely related to fiber quality. Operators might contaminate the end faces of the pigtails or the Line port of the RAU, resulting in different end face environments before and after the replacement and different maximum gain of the RAU board. Fiber quality indicators include: a. Whether the insertion loss of long fibers is normal. b. Whether there are points of insertion loss change (detectable by OTDR meters). c. Whether the end faces of the fibers at connection points within 20 km of the near end have been burned (fiber splicing needed) or dirty (cleaning needed). Fiber end face microscopes can be used to observe whether the end faces are clean (For detailed instructions, see RAU Deployment Guide). d. Whether the pigtails at the near end have a bend radius of less than 3 cm. 2. Under certain conditions, the customer lines cannot be rectified in a short time. The actual maximum gain of the Raman board is only 5 dB or 6 dB (stable) whereas the system stability is excellent. Will the system run stably in this condition for a long time? Are there any pigtail burning risks? Answer: No long-term testing has been carried out in Huawei R&D labs. If the actual maximum gain of the Raman board is only 5 dB or 6 dB (stable), Huawei cannot fully guarantee long-term stable running. Due to extremely high reverse output power of Raman boards, even slight abnormalities at the near end can cause the Raman amplifiers' failure to reaching the standard maximum gain. As a result, the system may not able to run stably in a long-term, leaving potential risks for future maintenance. Therefore, the customers are advised to rectify optical fibers. 3. The Raman lasers were closed before line operations, but the pigtails of some sites are still burned. Why cannot the mechanisms such as IPA or return loss detection avoid fiber burning? Answer: Return loss detection cannot avoid 100% fiber burning. Instead, it lowers the fiber burning probability. The optics mechanism of return loss detection is that using detection light with lower power to ensure no fiber burning when the laser is turned on, and a part of the detection light are reflected to the Raman module when it reached the end face. The Raman module uses the ratio between the power of the detection light and reflection light (return loss) to determine whether the end face is normal. However, in actual situations, even the end face is already dirty, there is a low probability that the measured return loss can still be normal due to the random reflection angles, and the Raman laser will be turned on, and the fibers will be burned. To avoid these issues, the customers should be notified of the risks and requirements about Raman boards in advance. If abnormal line attenuation occurs, the customers should be encouraged to use fiber splicing for handling.

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