Fluke CableAnalyzer DSX-5000, Техническое справочное руководство, Страница: 536 / 700

Versiv Series Cabling Certification Product Family
Technical Reference Handbook
500
Table 20. Causes of OTDR Test Failures (continued)
GPU33.EPS
The trace shows a large reflective event with
high loss (top) or excessive tailing (bottom). The
tester can possibly show it as the End event,
though it occurs before the end of the link.

The event is a dirty, scratched, cracked,
misaligned, or unseated connector.
Misaligned or unseated connectors can also
cause large reflections that produce ghosts.
Clean and inspect the connection, then do
the test again.

A good connector has a sharp bend or
crack within its dead zone. The tester can
possibly show a sharp bend as a break,
especially at longer wavelengths or in
Manual OTDR mode with smaller
resolution settings.

The event is a crack in the fiber. Use a visual
fault locator to find the fault.

The event is a bad fusion or mechanical splice or a sharp bend.

The event is a connection between mismatched fibers (different
backscatter coefficients, core sizes, numerical apertures, or other
parameters). The top example could be caused by a larger core (on the
left) connected to a smaller core. Do an OTDR test from the other direction
and look for a reflective event that has a gain.

The launch cord has PC or UPC connectors, but the link has APC
connectors.