Viavi T-BERD 6000A V2, Руководство пользователя

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Chapter 5 Power meter, VFL (Visual Fault Locator) & Talkset
VFL Function
User Manual 76100000200 Rev. 001 29
1 Fix the plug over the optical input of the power meter so that no light
can reach the photodiode of the power meter. If the zero adjustment
is made without this plug, an error message may be displayed, as
the photodiode will detect too much light.
2 In the Results page, press the ( Powermeter Config. >) Zero soft
key and validate.
Carrying out the reference measurement
1 Fix the adapter corresponding to the jumper to the optical connector
of the power meter.
2 Connect the jumper between the input of the power meter and the
output of the source.
3 Configure the same wavelength on the source and the power meter.
The power measured is displayed in the results page of the power
meter.
4 Press the ( Pow Reference >) Standard Ref soft keys to save the
result displayed as reference value.
Measurements on the fiber under test
After defining the reference value, proceed as follows to make the
measurement:
1 Fix the jumpers and connectors needed to connect the fiber to be
tested between the source output and the power meter input.
2 In the set-up menu, select dB units.
3 The power displayed in the Power Meter window corresponds to the
optical loss of the link tested. It can be displayed in the table (see
"Table of results" page 27 ).
VFL Function
VFL connector
The type of optical connector used for the VFL source is UPP (Universal
Push Pull), which is compatible with all diameter 2.5 mm connectors (FC,
SC, ST, DIN, E2000, etc.).
See
Figure 10 on page 24 to visualize the VFL connector.
Visual Fault
Locator
function (VFL)
This function is used to emit a red light signal of frequency 1 Hz or in
continuous mode into a fiber to detect any defects in the dead zone of the
reflectometer, or to identify it.