Fluke DTX-GFM2, Руководство пользователя

Страница: 18 / 62

DTX-MFM2/GFM2/SFM2 Fiber Modules
Users Manual
12
W
Caution
Do not disconnect the reference test cords from
the testers' output ports after setting the
reference. Doing so may alter the amount of
optical power launched into the fiber and
invalidate the reference.
Reference values should not change by more than a few
tenths of a dB from day to day. Larger changes may
indicate a problem with the reference test cords or
connections.
See the sections on Smart Remote, Loopback, and Far
End Source modes for details on setting the reference for
each mode.
Selecting Reference Test Cords
The DTX Fiber Modules come with high-quality reference
test cords.
To ensure that your measurements are accurate and
repeatable, use reference test cords provided by Fluke
Networks or cords of the same quality. See "Replacing
Fiber Reference Test Cords" on page 47.
Testing Your Reference Test Cords
You should test your reference test cords before each
job. Use another set of known-good reference test cords
to set a reference and run an Autotest on each cord. Use
Smart Remote mode to test two reference test cords at a
time, or Loopback mode to test one cord. See pages 21
and 26 for details on running these tests.
Using Mandrels for Testing Multimode Fiber
You should use mandrels when testing multimode fiber
with the DTX-MFM2 fiber modules. Mandrels can
improve measurement repeatability and consistency.
They also allow the use of LED light sources to certify 50
µm and 62.5 µm fiber links for current and planned high
bit-rate applications, such as Gigabit Ethernet and 10
Gigabit Ethernet.
W
Caution
Do not use mandrels when testing with the
DTX-GFM2 fiber modules.