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3.5 Fiber GRI
The Graded Refractive Index
(GRI) of fiber cables differs
depending on the
manufacturer. So that you can
get accurate length results for
different cables, CertiFiber has
user-definable GRI values for
both test wavelengths.
The default GRI values used
for a 62.5-micron cable are
1.5014 at 850 nm and 1.4966 at
1300 nm. If you are using 50-micron cable and
do not have the GRI values published by the
fiber manufacturer, the defaults should be set
to 1.4897 at 850 nm and 1.4856 at 1300 nm.
The standard GRI values for 62.5-micron
fiber produced before 1994 are 1.478 at
850 nm and 1.422 at 1300 nm.
1. To display the Fiber GRI setup screen,
use the down-arrow key to scroll to Fiber
GRI in the Setup screen and press Enter
or F1 (Select).
2. Press F2 (Select) to highlight the GRI to
be changed.
3. Use the up- or down-arrow key to
increase or decrease the value by
.0001 dB, or use the left- or right-arrow
key to increase or decrease the value by
.01 dB.
4. Press F1 (Save) to save the settings and
return to the Setup screen.
CERTIFIBER™
