Diagnosing Otdr Test Failures - Fluke OF-500-10 Technical Reference Handbook

Diagnosing OTDR Test Failures

Tables 3-6 and 3-7 describes some typical causes of OTDR
test failures.
See also the table in Appendix C, which shows results
from a survey on common causes of fiber link failures.
OVERALL LOSS fails
•
There is one or more dirty or damaged connections in the cabling. Check the OTDR trace or event table for
high-loss reflective events.
•
The wrong fiber type is selected on the OTDR tab in Setup.
•
A patch cord, launch fiber, or fiber segment has the wrong core size, backscatter coefficient, or mode field diameter.
If the patch cords and launch fiber are the correct type, check the OTDR trace for mismatched cable in the cabling.
•
The cabling has a bad fusion or mechanical splice or a sharp bend. Use the OTDR trace or event table to locate these
faults.
Table 3-6. Diagnosing OTDR Test Failures
OVERALL LOSS may show a WARNING if the first or last event is hidden.
Tip: If a trace shows multiple failing or unusual events,
it's usually best to start looking for faults at the
nearest event. Some faults can cause misleading
events farther down the cabling.
Note
Using the OTDR
Diagnosing OTDR Test Failures
3
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