Instructions

Measuring Loss
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Measuring Loss
The loss measurement shows how much optical power is
lost in a link’s fiber and connectors.
About 1 Jumper Connections
The reference and test connections shown in this section
produce 1 Jumper results. 1 Jumper results include the loss
of the fiber plus the loss of the connections at both ends of
the link. This is the most commonly used method for testing
installed fiber links. Other methods are shown in Appendix
D.
1 Jumper connections require connector adapters that
match the connectors in the link under test. If you do not
have the correct connector adapters, see Appendix D for
alternative connections that produce 1 Jumper results.
Testing the Test Reference Cords
You must test your test reference cords at regular intervals.
Use the procedure given in Appendix A.
About Referencing
The reference serves as 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 reference 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 reference cord to the
source.
 Anytime you see a negative loss measurement.
Setting the Reference
You may set the reference from power or loss mode. Fluke
Networks recommends using power mode because the
meter shows the actual power level produced by the
source. In loss mode, the meter shows the difference
between the power level and the previous reference level.