LANTEK User Manual - Ideal Industries

Chapter 3
Structured Cable Field Calibration and Testing
The following troubleshooting tips identify typical cable conditions and their
corresponding screen plots.
Condition
Open, Near End
Short, Near End
Open, Far End
Short, Far End
Split Pair
Cable segment with higher
than nominal impedance
Cable segment with lower
than nominal impedance
Level Plot, much higher
than the known cable NVP
No distinct upswing or
downswing at the Far End
TDR Plot Indication
Upswing develops early. In comparison to good cable pairs,
this pair appears shorter in length.
Downswing develops early. In comparison to good cable pairs,
this pair appears shorter in length.
Fully developed upswing at the Far End.
Fully developed downswing at the Far End.
20% to 30% rise in relative impedance at the split with a
corresponding drop in impedance where the pair is
reconnected.
Peak in the level area of the plot.
Dip in the level area of the plot.
Wrong cable type selected, or wrong cable type installed.
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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