Fluke MultiFiber Pro, User Manual

Page: 27 / 68

How to Measure Loss
17
About the Reference
The reference is the baseline power level for loss
measurements. Regular referencing helps account for minor
variations in source power and connection integrity. Also,
since the reference is the baseline for measurements, the
losses of the test cords and adapters used for referencing are
excluded from test results.
For the most accurate test results, you should set the
reference at these times:

At the beginning of each day.

Anytime you reconnect a test cord to the source.

Anytime you see a negative loss measurement.
Set the Reference for Loss Measurements
 Caution
For correct measurements, connect only APC
connectors to the singlemode sources. Connect
only non-APC connectors to the multimode
source.
For singlemode links with APC connectors, you
must use Type A test cords and adapters. Type A
components correctly align the angles in the
connectors.
1 Clean the connectors on the meter, source, and a test
cord.
2 Turn on the meter and source and let them warm up
for 10 minutes. Allow more time if the equipment has
been stored above or below ambient temperature.
3 Make connections to set the reference. Figure 8 on
page 19 shows reference connections for links with
unpinned connectors. Appendix B shows connections
for links with other types of connectors and for fiber
modules.On the source, hold down

for 2.5 seconds
to see the setup menu, then select these settings:

SCAN ALL : ON

MODE : 2 kHz does not show
4 On the meter, press

to make SET REF show.
5 If necessary, press

CHANNEL to see the power
measurement for each channel to make sure they are
satisfactory.
(continued)