Get Properly Connected -- Understanding Cat 5 Network Cable Connectors
Have you ever looked at the modular connectors on the ends of a cat 5 network cable? There are a lot of little wires going into a bunch of little slots in the connector. If you are making up your own cat 5 network cables, you will need to install these connectors properly on each end of your cable.
Understanding the layout/arrangement of the wires in a cat 5 network cable connector is confusing for many people -- but it really doesn't need to be. Here's some basic information to help you --
In cat 5 network cable, you will find eight small wires, typically wound into four pairs of two wires each. Usually you will find these cat 5 network cable wires distinguished by the color of their sleeve: Brown, paired with a wire that has brown/white, orange paired with an orange/white, blue paired with a blue/white, and a green wire paired with a green/white. As you can see, each solid-colored wire in the cable is paired with a wire of the same color with white added.
Your job, when attaching the connector to your cat 5 network cable, is to put the proper colored wire in the proper slot -- and that's where it gets interesting. There are two different ways to do the connector wiring, two different "patterns" as it were: T568A and T568B. It really doesn't make any difference which you use, as long as you wire both ends of your cat 5 network cable the same (unless you're making a cat 5 "crossover cable" -- in which case see our separate article on this subject). The T568A and T568B schemes simply specify which colored wire is to go into which slot (called a "pin") in your connector. Unless you are making a crossover cable, you will be wiring the pins for your cat 5 network cable so that pins 1-8 on one connector will be wired to the same color as pins 1-8 on the other connector -- this is called a "straight through" connection. Another thing to note is that that pins on your cat 5 network cable form a pair: 1 and 2, 3 and 6, 4 and 5, 7 and 8. These pair formations are identical with either cat 5 network cable wiring scheme, the only difference is what color wire goes into each pin. If you look at your cat 5 network cable connector so that all the pins are facing you, and the little hook is facing away from you, then the pins run from 1-8, from left to right. If you are using the T568A scheme to wire your cat 5 network cable connector, then the wires will run in this order: (1) White/green (2) Green (3) White/orange (4) blue (5) white/blue (6) orange (7) white/brown (8) Brown. If you are using the T568B scheme, on the other hand, you will need to wire your cat 5 network connector with the wires in this order instead: (1) White/orange (2) orange (3) White/green (4) blue (5) white/blue (6) Green (7) white/brown (8) Brown. As you can see, the only difference between these two cat 5 network cable connector wiring schemes is that the orange and green colored wires (with their white counterparts) are switched around. Once again, unless you are making a crossover cable, the only thing to be careful of is to make sure that you do not use one wiring scheme for one end of your cat 5 network cable, and a different scheme for wiring the other end of the same cable. Additionally, you can find cat 5 network cable connector diagrams which illustrate the wire color and position -- they are a great help to understand and visualize the layout, and you can compare your own wiring job with the illustrated diagram, to make sure you have done the wiring correctly before you crimp the cat 5 network cable connector together.
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