Fluke Versiv, User Manual

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Versiv Cabling Certification Product Family
Users Manual
156
About Launch and Tail Cords
Launch and tail cords let the tester measure the loss and
reflectance of the first and last connectors in the cabling and also
include them in the measurement of overall loss. Without launch
and tail cords, no backscatter is available before the first
connector nor after the last. To measure the properties of a
connector, the tester must measure the backscatter before and
after the connector.
Fluke Networks recommends that you use launch and tail cords.
You should also use the launch/tail cord compensation function
to remove the lengths of these fibers from the OTDR
measurements.
If you select a test limit that requires you to use launch and tail
cords, the tester shows a warning message when you try to do an
OTDR test without launch and tail cords.

Caution
For tests on cabling that has angled physical contact
(APC) connectors, use only launch/tail cords that
have APC connectors at the ends connected to the
cabling. Other connector types cause large
reflections that can cause unreliable test results.
Notes
Do not use hybrid patch cords to connect the
launch or tail cords to the cabling under test. Use
launch and tail cords with the correct connectors
to connect directly to the cabling under test. This
gives the best measurement of the first and last
connectors in the link. Launch and tail cords with
different types of connectors are available from
Fluke Networks.
Tail compensation usually gives the most
accurate measurements.
The style of the case for your launch/tail cords can
be different from the cords shown in this manual.