User guide

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OMNIScanner User Guide
Measurements with OMNIFiber
Length/Delay
The Length/Delay function measures a fiber’s length and propagation
delay. Length measurements are derived from the propagation delay
results using the GRI (Graded Refractive Index) at the appropriate wave-
length.
Propagation Delay is the measure of the time required for a signal to
advance from one end of the link to the other. When measuring propaga-
tion delay, OMNI Scanner measures the round trip delay through both
fibers, and them divides the result by two, assuming that the cables are
equal in length.
Propagation Delay cannot be measured on a single fiber; duplex fiber must
be used. Single fiber must be measured using the Loopback Method. (See
Chapter 8 - Loopback Autotest for detailed information.)
OMNI Scanner measures the full length of the fibers under test.
The LENGTH/DELAY screen displays the GRI @
1300 nm (nanometers).
The length limit and the actual derived length are
displayed in meters or feet.
The delay is displayed in nanoseconds (nS).
Press ESC to exit the LENGTH/DELAY screen.
Loss
The Loss function measures the signal loss in a fiber optic cable. The
adapters inject a signal into the fiber cable and OMNI Scanner and OMNI-
Remote measure the received signals at 850 and
1300 nm for multimode fiber cables and 1310 for
single-mode fiber cables.
The LOSS screen displays the measured power in
dBm (decibels; one milliwatt reference) for each
wavelength.
The measured loss and limit values in decibel (dB)