Currently, twisted-pair copper cabling (particularly the UTP cabling) is most ubiquitous for LAN and telephone installations. The main method to put connectors on twisted-pair cables is crimping. You could use a cable crimping tool to push the metal contacts inside the connector onto the individual conductors in the cable, thus making the connection. This tutorial tells you how to install the twisted-pair cable connectors step by step.
Types of Twisted-Pair Cable Connectors
There are mainly two types of connectors/plugs used for connectorizing twisted-pair cables in voice and data communications installation.
RJ-11 connectors were historically used in both business and residential telephone applications because of their small form factor and simplicity, and they remain in widespread use in homes.
RJ-45 connectors are used primarily in LAN applications because of the number of conductors they support (eight total). Current recommendations are to install RJ-45 jacks for telephone applications because those jacks support both RJ-11 and RJ-45 connectors.
Both the two connectors are made of plastic with metal "fingers" inside. The fingers are pushed down into the individual conductors in a twisted-pair cable during the crimping process. Once the fingers are crimped and make contact with the conductors in the twisted-pair cable, they are the contact points between the conductors and the pins inside the RJ-11 or RJ-45 jack.
Tips: Notice that these connectors are basically the same, except the RJ-45 accommodates more conductors and thus is slightly larger. And the RJ-11 type connector is only configured with two metal contacts instead of six while having six positions. This is a common cost-saving practice on RJ-11 type plugs when only two conductor contacts will be needed for a telephone application. Conversely, you rarely see an RJ-45 connector with less than all eight of its positions configured with contacts.
Types of Twisted-Pair Cables
There are two types of twisted-pair cables according to the RJ connectors.
Stranded-Conductor Twisted-Pair Cable
Stranded-conductor twisted-pair cable is made up of many tiny hairlike strands of copper twisted together into a larger conductor. These conductors have more surface area to make contact with but are more difficult to crimp because they change shape easily. Because of their difficulty to connectorize, they are usually used as patch cables.
Solid-Conductor Twisted-Pair Cable
Most UTP cable installed in the walls and ceilings between patch panels and wall plates is solid-conductor cable. Although they are not normally used as patch cables, solid-conductor cables are easiest to connectorize, so many people make their own patch cords out of solid conductors.
Tools for Connector Crimping
There are mainly three tools which are needed in the coming installation.
Fiber Cable Stripper
The first tool is a cable-jacket stripper. It will only cut through the outer jacket of the cable, not through the conductors inside. Many different kinds of cable strippers exist, but the most common are the small, plastic ones that easily fit into a shirt pocket. They are cheap to produce and purchase.
Cable Connector Crimper
A cable connector crimper is needed when installing connectors on UTP or STP cable. Many different styles of cable crimpers can crimp connectors on UTP or STP cables. Here is an example of a crimper that can crimp both RJ-11 and RJ-45 connectors.
Network Cable Tester
The last tool you are going to use is a cable tester. This device tests for a continuous signal from the source connector to the destination and also tests the quality of that connection.
Now we will go over the steps for installing the connectors. Pay particular attention to the order of these steps and be sure to follow them exactly. Equipment from some manufacturers may require you to perform warning slightly different steps. Check the manufacturer's instructions before installing any connector.
Step 1: Measure the cable you want to put ends on and trim it to the proper length using the cable cutter.
Step 2: Use the cable stripper to strip about 1.5" of the jacket from the end of the cable. Then, rotate the stripper around the cable twice. This will cut through the jacket.
Step 3: Remove the stripper from the cable and pull the trimmed jacket from the cable, exposing the inner conductors. If a jacket slitting cord (usually a white thread) is present, separate it from the conductors and trim it back to the edge of the jacket.
Step 4: Untwist all the inner conductor pairs and spread them apart so that you can see each individual conductor.
Step 5: Line up the individual condutors so that the color code matches the color-coding standard you are using.
Step 6: This step includes two points. First, trim the conductors so that the ends are even with each other, making sure that the jacket of the cable will be inside the connector. Second, the total length of exposed connectors after trimming should be no longer than 0.5" to 0.625".
Step 7: Insert the conductors in the connector, ensuring that all conductors line up porperly with the pins as they were in the previous step. If they don't line up, pull them out and line up. Do this carefully, as it's the last step before crimping on the connector.
Step 8: Carefully insert the connector and cable into the crimping tool, which has two dies that will press into the connector, and push the pins in the connector into the conductors inside the connector. Now the installation is done.
After the whole installation, you should check to ensure all conductors are making contact and that all pins have been crimped into their respective conductors. If the connector didn't crimp properly, cut off the connector and redo it.