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Appendix:
Optical fiber loss measurement
Step 1- Optical Reference Level
Turn on optical
power meter and press the λ key to select the wavelength.
Turn on optical light source (emitting source) and select the wavelength.
Wait for 1-2 minutes until it stabilize.
Select a piece of patch cords, which is used to connect with the light
source, we call it emitting patch cords. Cleaning connector of the patch
cords. The fiber of the emitting source patch cords must be the same fiber
type as the fiber under test.
Connect the light source (emitting source) with the 7940 through the
emitting source patch cords
SEFRAM 7940 get the power measurement value. This value should be
close to the one that light source (emitting source) set. If it has wide
disparity, please make sure the fiber connection is clean properly else
replace another jumpers.
Press the dB key; the reading 0.00dB will be displayed on the screen. The
tested power values will be set to the reference value.
Step 2-Optical Loss Measurement
Keep the emitting source patch cords connection with the light source
(emitting source).
Connect the 7940 and light source (emitting source) to the optical fiber
link respectively.
Notes:
cleaning all the connectors surface including all the necessary optical
adaptors. The reading in dB unit displayed on the screen is the tested optical
fiber link loss.(also display the current absolute optical power value in dBm
unit).
