During Autotesting, CertiFiber measures
a cable’s Loss, Length, and Delay:
Optical Power Loss is a measurement of the
signal loss in a cable. A signal is injected into
the fiber cable by the Remote unit. CertiFiber
measures the received signal to determine loss.
It displays the loss in decibels (dB), as well as
the margin values, for both wavelengths.
Length measurements are derived from the
propagation-delay results by using the cable’s
GRI (Graded Refractive Index) at the
appropriate wavelength. CertiFiber measures
the full length of the fibers under test. (See
Section 3.5
for information on how to change
the GRI values.) In the Autotest Results screen,
the length is displayed in meters or feet
depending on how your unit is set up. (See
Section 3.2
.)
Propagation Delay is a measurement of the
time required for a signal to advance from one
end of the circuit to the other. When
measuring propagation delay, CertiFiber
measures the round-trip delay through both
fibers, and then divides the result by two,
assuming that the cables are equal in length.
Propagation delay cannot be measured on a
single fiber; duplex fibers must be used. The
Autotest Results screen displays the
Propagation Delay in nanoseconds (ns).
CERTIFIBER™
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