NFK3-SC FLUKE NETWORKS, NFK3-SC Datasheet - Page 57

• Manufacturer Part Number: NFK3-SC
• Description: LAN Tester
• Manufacturer: FLUKE NETWORKS

Specifications of NFK3-SC

• Lead Free Status / RoHS Status: na

Changing the Index of Refraction
The index of refraction is the ratio of the speed of light in a
vacuum to the speed of light in a fiber. The tester uses the
index of refraction to determine fiber length.
You can change the index of refraction on the Cable tab in
Setup.
When MANUAL CABLE SETTINGS on the Cable tab is
disabled, the tester uses the n values specified in the
selected fiber type.
When MANUAL CABLE SETTINGS is enabled, the tester uses
the n values you enter.
The n values defined in the fiber types are suitable for most
applications. Minor differences between the tester's n and a
fiber's actual n usually do not make enough difference in
length to fail a fiber.
You may want to change the index of refraction if
•
•
Increasing n decreases measured length.
To use the default n values specified in the selected fiber
type, set MANUAL CABLE SETTINGS to Disabled.
The customer wants you to use a specific n value for
the job.
The cable's fibers are longer than its jacket, and you
need to precisely locate a point on the cable (such as a
fault). In this case, adjust n until the measured length
matches a known length of fiber.
If you try to enter a value outside the valid range
for n, the tester shows N/A for the value. The valid
range is 1.1 to 1.71 inclusive.
Getting Started Testing Fiber
Note
General Test Settings
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