Possible Cause
Judgment Criterion
Troubleshooting Method
The quality of optical
fiber splicing is poor. For
example, the splicing
point has air bubbles.
NOTE
Poor optical fiber splicing
leads to unstable
transmission of optical
signals. As a result, packet
loss occurs.
1. Test the backbone fiber and
branch fiber by using the
OTDR. It is found that
abnormal return loss points
exist on the optical fiber.
2. Check the optical fiber
splicing points by using the
magnifying glass on site. It
is found that the splicing
points have quality
problems, for example, air
bubbles exist.
Splice the optical fiber again.
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.
1. Test the backbone fiber and
branch fiber by using the
OTDR. It is found that
abnormal return loss points
exist on the optical fiber.
2. Check the optical fiber
connectors on site. It is
found that the optical fiber
is not firmly connected or
PC connector (blue) and
APC connector (green) are
interconnected.
l
If the optical fiber is not
firmly connected, reconnect
the optical fiber firmly.
l
If different types of optical
fiber connectors are
interconnected, replace the
incompatible connector
with a compatible one or
replace relevant devices,
such as the optical splitter.
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.
1. Check the backbone fiber
and branch fiber by using
the OTDR. It is found that
optical signals attenuate
seriously.
2. Check the optical path on
site. It is found that the
multi-mode optical fiber is
used. The multi-mode
optical fiber can be
recognized by its physical
features such as its color.
Replace the multi-mode optical
fiber with the single-mode
optical fiber.
SmartAX MA5612 Multi-service Access Module
Maintenance Guide
6 System Fault Handling
Issue 01 (2012-07-25)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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