NOTE
Assume that end faces are clean in the preceding test.
Possible causes
1.
A direct modulation optical transmitter is used. It is recommended that it be replaced
with an outer modulation optical transmitter.
NOTE
l
The 1550 nm optical transmitters are divided into two types: outer modulation optical
transmitter and direct modulation optical transmitter.
l
Compared with the direct modulation optical transmitter, the outer modulation optical
transmitter can better suppress SBS.
2.
The input patch cord of the CATV connected to the EDFA or the corresponding port of
the optical splitter is dirty or damaged.
Procedure
1.
Replace the optical transmitter with a 1550 nm outer modulation optical transmitter
whose SBS threshold is greater than or equal to 18 dBm if a direct modulation optical
transmitter is used.
2.
Ensure that the input end face of the CATV is clean and the input optical power of the
EDFA is normal.
3.
Contact Huawei technical support engineers if the MER value is still abnormal after the
preceding two steps are performed.
3.3 Common Fan Module Faults
3.3.1 The Fan Cannot Rotate
Symptom
The fan stops rotating.
Possible causes
The fan is faulty.
Procedure
Contact Huawei technical support engineers.
3.3.2 The Fan Rotates at Full Speed All the Time
Symptom
The fan rotates at full speed all the time.
EDFA0820-D
Routine Maintenance Guide
3 Common Troubleshooting
Issue 02 (2018-07-02)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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