Fluke Networks CertiFiber Pro Users Manual - Manual (Page 273)

Chapter 9: How to Use the OptiFiber Pro OTDR Module
OTDR Results
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End
The end of the fiber
The End event always shows N/A for loss because
backscatter measurements are not available on
both sides of the event.
The tester does not give a PASS/FAIL status to
this event, unless you use a custom test limit that
includes a limit for segment attenuation, and the
segment before the End event fails.
Hidden End
The end of the fiber is in
the attenuation dead
zone of the previous
event.
The tester cannot give an accurate distance to
the end of the fiber because the end is hidden.
The tester does not give a PASS/FAIL status to
this event.
Hidden
The event is in the
attenuation dead zone
of the previous event.
The tester detected the event, but does not have
enough information to measure its loss
separately from the previous event. Thus, the
tester includes the loss of the hidden event with
the loss of the previous event. The loss of the
hidden event shows as N/A.
A hidden event is often the end of a patch cord
that is hidden in the dead zone made by the first
connector on the cord.
To get a better view of hidden events, do a
Manual OTDR test with the Averaging Time set
to Best Resolution. Narrow pulse widths can also
help you see hidden events.
If the event is not a connection, inspect the fiber
near the location of the event. Use a visual fault
locator to see faults such as cracks or breaks in
the fiber.
The tester does not give a PASS/FAIL status to
this event, unless the test limit has a limit for
reflectance and the hidden event exceeds the
limit.
(continued)
Table 11. Event Types (continued)