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CHAPTER 8: Testing Twisted-Pair Cable
Figure 8-4 illustrates an example of a split pair where pins 1 and 2 are split
with 3 and 6.
Refer to the
Section 8.2.2
for an explanation of NEXT.
Figure 8-4. Split Pair.
NOTE
A split pair cannot be detected with a simple DC continuity check.
Most wiring problems can be found at the termination points. A chart of
common wire map problems and suggested solutions is shown below.
Test Results
Possible Solutions
Crossed Pair
Depending on what the cable is being used for, this may be
okay. A crossed-pair cable is common for a 10BASE-T
application when connecting two hubs.
Double-check the desired specifications for that segment and
re-terminate the segment to correct the wiring if necessary.
If the problem continues, follow the possible solutions for “OPEN
on one or more of the pairs” on the next page.
1
2
3
6
4
5
7
8
1
2
3
6
4
5
7
8
1,2 splits 3,6
