IDEAL INDUSTRIES FIBERTEK, Руководство пользователя

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Chapter 3
Structured Cable Field Calibration and Testing
3-38
The following troubleshooting tips identify typical cable conditions and their
corresponding screen plots.
Condition TDR Plot Indication
Open, Near End Upswing develops early. In comparison to good cable pairs,
this pair appears shorter in length.
Short, Near End Downswing develops early. In comparison to good cable pairs,
this pair appears shorter in length.
Open, Far End Fully developed upswing at the Far End.
Short, Far End Fully developed downswing at the Far End.
Split Pair 20% to 30% rise in relative impedance at the split with a
corresponding drop in impedance where the pair is
reconnected.
Cable segment with higher
than nominal impedance Peak in the level area of the plot.
Cable segment with lower
than nominal impedance Dip in the level area of the plot.
Level Plot, much higher
than the known cable NVP
Wrong cable type selected, or wrong cable type installed.
No distinct upswing or
downswing at the Far End Matched terminator attached to the cable. The pair appears to
have a very long length.
STORING, RETRIEVING, AND DELETING TDR RESULTS
Storing a Graph
The TDR results can be stored in the Current Job.
1. Press the UP/DOWN ARROW keys to select the desired cable pair graph.
2. Press SHIFT key to save/print.
3. Select . The Save Test screen appears. Press SHIFT to bring up the “Save
As” or “Rename” selection if the test has already been stored.
4. The test name is automatically assigned. If a different name is desired, press
DELETE to change the highlighted character(s).
5. When you have entered the name, press ENTER to accept the changes and return
to the ready screen.
Retrieving or Deleting a Graph
For detailed instructions regarding retrieving or deleting stored TDR results, refer to
Viewing or Deleting Stored Autotest Results.
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