Fluke Networks CertiFiber Pro Users Manual - Manual (Page 280)

Versiv Cabling Certification Product Family
Technical Reference Handbook
258
 LIMIT: The maximum loss allowed by the selected test limit for
each wavelength the tester used. N/A shows if there is no test
limit for the measurement.
 MARGIN: The difference between the limit and the measured
loss for each wavelength the tester used. Margin is negative if
the loss exceeds the limit. N/A shows if there is no test limit for
the measurement.
 Tap to see help for this screen.
 To see details for the event before or after this one, tap or
next to Events.
 The Min/Max control shows if the test limit has a minimum and
maximum value for the measurement. Tap the control to see the
values. Most industry-standard limits do not have minimum
values.
 REFLECTANCE: Reflectance is the return loss for one event. It is
the ratio of the light reflected at one point on the fiber to the
light that gets to that point from the source. Reflectance values
are in units of negative decibels. A smaller (more negative)
reflectance value shows that less light is reflected back to the
source. For example, a reflectance of -45 dB shows for a good
multimode connection. A reflectance of-20 dB shows for a bad
multimode connection that reflects more light back to the OTDR.
Reflectances that exceed the measurement range of the tester
show a ">" (greater than) symbol. If any reflection shows ">",
ORL shows "<" (less than).
Reflectances from hidden events can possibly show “<" because
the tester cannot measure the backscatter before the event.
Note
Reflectance measurements are affected by the
backscatter value you enter on the TEST SETUP
screen.