Modular wall plates are the most common type of wall plate in use for data cabling because they meet the various ANSI/TIA and NEC standards and codes for quality data communications cabling. So modular wall plates have the widest variety of jack types available. All the jacks available today differ based on a few parameters, including the following:
- Wall plate system type
- Cable connection
- Jack orientation
- ANSI/TIA-568-C.2 and -C.3 wiring pattern
Wall Plate System Type
Remember how the type of wall plate you use dictates the type of jacks for that wall plate? Well, logically, the reverse is also true. The interlocking system that holds the jack in place in the wall plate differs from brand to brand. So, when you pick a certain brand and manufacturer for a jack, you must use the same brand and manufacturer of wall plate.
Cable Connection
Jacks for modern communication applications use insulation displacement connectors (IDCs), which have small metal teeth or pins in the connector that press into the individual wires of a UTP cable (or the wires are pressed into the teeth). The teeth puncture the outer insulation of the individual wires and make contact with the conductor inside, thus making a connection. This process (known as crimping or punching down, depending on the method or tool used) is illustrated in Figure 1.
Though they may differ in methods, any connector that uses some piece of metal to puncture through the insulation of a strand of copper cable is an IDC connector.
Jack Orientation
Yes, jack orientation. The individual wall plate systems use many different types of jacks, and some of those systems use jacks with positions other than straight ahead (which is the "standard" configuration). These days, a popular configuration is a jack that's angled approximately 45 degrees down. There are many reasons that this jack became popular. Because it's angled, the cable-connect takes up less room (which is nice when a desk is pushed up tight against the wall plate). The angled connector works well in installations with high dust content because it's harder for dust to rest inside the connector. It is especially beneficial in fiber-to-the-desktop applications because it avoids damage to the fiber-optic patch cord by greatly reducing the bend radius of the cable when the cable is plugged in. Figure 2 shows an example of an angled connector.
Note |
Wiring Pattern
When connecting copper RJ-45 jacks for universal applications (according to the standard, of course), you must wire all jacks and patch points according to either the T568-A or T568-B pattern. Figure 3 shows one side of a common snap-in jack to illustrate that the same jack can be terminated with either T568-A or T568-B color coding. (You may want to see the color version of this figure in the color section.) By comparing Table 1 and 2, you can see that the wiring schemes are different only in that the positions of pair 2 (white/orange) and pair 3 (white/green) are switched. If your company has a standard wiring pattern and you wire a single jack with the opposing standard, that particular jack will not be able to communicate with the rest of the network.
Table 1 shows the wiring color scheme for the T568-A pattern. Notice how the wires are paired and which color goes to which pin. Table 2 shows the same for T568-B.
Pin Number
|
Wire Color
|
---|---|
1
|
White/green
|
2
|
Green
|
3
|
White/orange
|
4
|
Blue
|
5
|
White/blue
|
6
|
Orange
|
7
|
White/brown
|
8
|
Brown
|
Pin Number
|
Wire Color
|
---|---|
1
|
White/orange
|
2
|
Orange
|
3
|
White/green
|
4
|
Blue
|
5
|
White/blue
|
6
|
Green
|
7
|
White/brown
|
8
|
Brown
|