Triple-Play Service Deployment

Chapter 3: Deploying and Troubleshooting Fiber Networks
Stage 4: PON feeder cable acceptance test
Before acceptance testing can begin, the technician must ensure
that both the connectors and patch cords (those used to test and
those in use on the network) meet network operator requirements
for insertion loss and reflectance.The tests may be performed either
with an OTDR (1310/1550 nm) or with a VFL operating in the 635-
670 nm range and a source/power meter/ORL meter combination.
With an OTDR, the test is performed from the CO or from the hub or
from both for bi-directional OTDR testing. To simplify testing, the
feeder cable acceptance test typically does not include the splitters.
If the does include the splitters, the process is complex and requires
a high performance (high dynamic range, short dead zone) OTDR
with the capability to test through splitters. The inputs of the
splitters are connected to the feeders, and one output of the splitter
to be tested is connected to a 2 km receive cable. Testing from the
CO (or eventually from the hub) then qualifies the feeder part and
the input/output of the splitter. To test the next output of the
splitter, the technician can move the receive cable from one output
to a different one and repeat the test from the CO (or the hub).
To expedite feeder cable acceptance testing, technicians may select
to test only one or a few outputs from the splitter. When the feeder
fiber link for a given splitter has been completely tested, the test
equipment at the CO and the hub can be moved to a different fiber
and the process is then repeated. It should be noted that receive
cable is the same as launch cable—it is simply used at the receive
end instead of the launch end.
If a source/power meter/ORL meter combination is employed, two
operators with test equipment are needed, one at each end of the
feeder cable. When the feeder cable acceptance test does not
include the splitters, one test set is connected to the CO and another
is connected to the hub connector just before the splitter. If the
feeder cable acceptance test does include the splitters, then the
process is more complex. In order to take the splitters into account,
the inputs of the splitters should be connected to the feeders. The
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