Chapter 6: Operation
Figure 6-25. LPV Level 1 Pass/Fail Summary Screen.
DELAY OK: The propagation delay of the cable is within specifi- cation.
SKEW OK: The skew of the cable is within specification.
NEXT OK, FEXT OK: Indicates that “near end crosstalk” (at the near connector) and at “crosstalk far end” (a distance removed from the near connector) is within acceptable limits. Crosstalk is interference created by signal coupling between adjacent wires of the cable.
SPLIT OK: The wire contains no split pairs. See Appendix D for a definition of "split pairs" and notes on making a correct cable.
MAP OK: The pair wiring of the cable is correct. See Appendix D.
PATCH/SOLID: The type of wire specified.
TOL(TOLERANCE): A calculated value using cable length, delay, NEXT, FEXT, cable category (CAT 3, 5, 5e, 6) and speed (10 Mbps, 100 Mbps, 1000 Mbps). Zero percent equals failure to meet specifications at a given speed. One percent is barely passing; 100 percent is maximum tolerance.
Tolerance is largely cable length driven. The longer the cable is, the less the tolerance. However, lower category cables eat up tolerance faster than higher category cables.
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