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CHAPTER 8: Testing Twisted-Pair Cable
The TSB-67 UTP Link Performance specification is becoming the
benchmark for installed UTP links and is the specification that the SCAN-
LAN Vt design is primarily based on.
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.
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