78
SCAN-LAN VI
8.2 Twisted-Pair Test Descriptions
The following test descriptions apply to testing four pair Unshielded
Twisted Pair (UTP). However, the fundamental concepts can be applied
to testing Shielded Twisted Pair (STP) and Screened Twisted Pair (ScTP)
cable.
8.2.1 W
IRE
M
AP
Wire map is used to test the continuity of a cable and also to check for split
pairs. Continuity is the electrical connection of a wire from one end of the
cable to the other.
Typically when testing twisted-pair cable, it’s best to have all wires
connected straight-through. Straight-through means that pin 1 of the
connector on one end is connected to pin 1 of the connector on the
other end, pin 2 is connected to pin 2, 3 to 3, and so on.
Figure 8-2 illustrates correct connectivity and pairing per the TIA-568
specification.
Figure 8-2. TIA-568 Connectivity Requirements.
Wire Map checks for shorts, opens, crossed pairs, reversed pairs, and other
wiring errors. Wire Map also checks the continuity of a shield if one exists.
When installing a new link or modifying an old link, it is very common to
accidentally create wiring errors. Figure 8-3 illustrates common continuity
wiring errors.
1
2
3
6
4
5
7
8
1
2
3
6
4
5
7
8
Summary of Contents for SCAN-LAN VI
Page 2: ......
