Viavi T-BERD 6000A V2, Руководство пользователя

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Chapter 5 Power meter, VFL (Visual Fault Locator) & Talkset
Using the Power meter
28 User Manual 76100000200 Rev. 001
– Standard Reference Selects the current result as reference value
to measure the attenuation of a link. This
reference is displayed under the measure-
ment result until a new reference value is
chosen.
– Keep Result Saves the result on the corresponding line
of the table.
– Clear Table Deletes all the results recorded in the table.
If the Source function is selected (on an OTDR module, either on this
Platform or on another one), the Power meter results page is different:
– The Wavelength , Unit and Zero menu keys are accessible via the
menu key Power Config.
– The Power Ref. menu key allows to reach the Standard Ref menu
key. It also allows to reach the Jumper Ref menu key if Power
meter function is associated with OTDR Source function onto
another unit (see 8100 Module User Manual).
Performing a
measurement
The power meter is started up as soon as the function is acti-
vated in the H
OME
menu.
Power
measurement
1 Connect the light source to be tested to the rear connector (see
"Connection to the power meter, VFL and Talkset" page 24 ).
2 In the S
ETUP
menu, choose the units dBm, dB or Watts.
3 Press the
S
TART
/S
TOP
key to start the measurement
.
The result will appear in the results page and can be memorized in
the table (see
"Table of results" page 27 ).
4 Press the
S
TART
/S
TOP
key to stop the measurement.
Optical link loss Setting the zero value of the power meter
Power measurement is automatically updated in consequence. The
value «<-60 dB» is displayed when the laser is switched off and if the
source output is looped on to the power meter input.
It is important to set the zero of the power meter before making any
measurements where accuracy is required, as the noise from the ger-
manium photodiode fluctuates over time and with variations in tem-
perature.