User Manual

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Appendix D. Making a correct UTP cable
Twisted Pair Cables: Unshielded twisted pair cable is used for
Base-T applications because it is inexpensive, easy to use and has
excellent noise cancelling capabilities. A minimum of two pairs of
twisted pair wire are required for each computer that connects to the
local area network:
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One pair of twisted pair wire to transmit data.
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One pair of twisted pair wire to receive data.
There are exceptions. 100 Base-T devices (called "T4") require 4
pairs of wires. Also, gigabit devices (1000MB) require 4 pair. In both
cases, 2 pair are used for transmit and 2 for receive.
As mentioned above, twisted pair cable has separate pairs of wires
twisted together to minimize crosstalk. If a wiring error is made
and one pair of wire is “split” with another ("split pairs"), the excess
crosstalk will most likely keep the link from operating properly.
To make a proper cable, fi rst choose a twisted pair cable that is
adequate for your application. For instance, CAT 5E cable for 100MB
and 1000MB applications. Use solid core wire when pulling inside a
wall. Use stranded cable ("patch cable") for jumpers.
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Remove the outer jacket of the twisted pair cable exposing
about a 6" of wire on each end of the cable.
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Each pair of wire must be twisted together (after crimping, the
wire should be twisted right up to the connector).
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Do not make the number one wiring mistake: "Split pairs" (a wire
from one pair is swapped with a wire from another pair).
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To minimize mistakes, use a standard color code throughout
your project. See the following page for the correct connector pin
numbers associated with each Base-T pair.
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Use good quality connectors and tools
APPENDIX