EXFO VFL, User Manual

Page: 17 / 43

Using the Optional Power Meters and VFL
Power Meter and VFL
13
Measuring Power or Insertion Loss
To perform power or insertion loss measurements using the auto
wavelength or auto switching modes of your source:
1.
If necessary, perform an offset nulling (see Nulling Offsets on page 4).
2. Check your fibers and clean them properly.
3. For insertion loss measurements, reference your power meter to a light
source (see
Setting Reference Values on Your Power Meter
on page 9),
then deactivate the light source.
4. If you have used a single reference patchcord, disconnect it
from the
power meter port only , then attach a second reference patchcord to
the power meter.
OR
If you have used two reference patchcords, disconnect both of them at
the bulkhead.
5. Using bulkhead adapters or the system patch panels, connect a fiber
under test to reference patchcord attached to the light source and
power meter.
I
MPORTANT
In auto wavelength or switching mode, there is a small delay (about
2 seconds per wavelength) allowed for refreshing the values. When
switching from one fiber to another, wait for these few seconds to
make sure that the measurement you are reading is not a residual
measurement from the previous fiber.