110-Blocks | Copper Cable for Data Applications

The telecommunications industry used the 66-style block for many years, and it was considered the mainstay of the industry. The 66-blocks were traditionally used only for voice applications; though we have seen them used to cross-connect data circuits, this is not recommended. The 110-blocks are newer than 66-blocks and have been designed to overcome some of the problems associated with 66-blocks. The 110-blocks were designed to support higher-frequency applications, accommodate higher-density wiring arrangements, and better separate the input and output wires.

The standard 66-block enabled you to connect 25 pairs of wires to it, but the 110-blocks are available in many different configurations supporting not only 25 pairs of wire but 50, 100, 200, and 300 pairs of wires as well. The 110-block has two primary components: the 110 wiring block on which the wires are placed, and the 110-connecting block (shown in Figure 1), which is used to terminate the wires. A 110-wiring block will consist of multiple 110-connector blocks; there will be one 110-connector block for each four-pair cable that must be terminated.

 
Figure 1: The 110-connector block

The 110-wiring block will consist of a few or many rows of 110-connector blocks. The wires are inserted into the connecting block and terminated by a punch-down tool or vendor-specific tool. These blocks are a type of IDC (insulation displacement connector); as the wires make contact with the metal on the blocks, the insulation is sliced, and the metal makes contact with the conductor. Remember, to prevent excessive crosstalk, don't untwist the pairs more than 0.5 inches for Category 5e, and 0.375 inches for Category 6 cable, when terminating onto a 110-connecting block.

The 110-blocks come in a wide variety of configurations. Some simply allow the connection of 110-block jumper cables. Figure 2 shows a 110-block jumper cable; one side of the cable is connected to the 110-block, and the other side is a modular eight-pin plug (RJ-45).

Photo courtesy of The Siemon Company

Figure 2: A 110-block to RJ-45 patch cable

Other 110-blocks have RJ-45 connectors adjacent to the 110-blocks, such as the one shown in Figure 3. If the application uses the 50-pin Telco connectors such as some Ethernet equipment and many voice applications do, 110-blocks such as the one shown in Figure 4 can be purchased that terminate cables to the 110-connecting blocks but then connect to 50-pin Telco connectors.

Photo courtesy of The Siemon Company

Figure 3: A 110-block with RJ-45 connectors on the front

Photo courtesy of The Siemon Company

Figure 4: A 110-block with 50-pin Telco connectors

You will also find 110-blocks on the back of patch panels; each 110-connecting block has a corresponding port on the patch panel. Figure 5 shows the 110-block on the back of a patch panel. The front side of the patch panel shown in Figure 6 shows a 96-port patch panel; each port will have a corresponding 110-connecting block.

Photo courtesy of Computer Training Academy

Figure 4: A 110-block on the back side of a patch panel

Photo courtesy of MilesTek

Figure 5: A 96-port patch panel

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Patch Panels and 110-Blocks

The patch panel with the 110-block on the back is the most common configuration in modern data telecommunication infrastructures.

When purchasing patch panels and 110-blocks, make sure you purchase one that has the correct wiring pattern. Most newer 110-blocks are color coded for either the T568-A or T568-B wiring pattern.

The 110-connecting blocks are almost always designed for solid-conductor wire. Make sure that you use solid-conductor wire for your horizontal cabling.