Connecting twisted pair 4 wires. Twisted pair pinout or how to crimp the connector of an Internet cable? What is twisted pair crimping?

Despite the apparent simplicity of the question and the availability of the necessary information on the network, difficulties may arise with twisted pair crimping, especially for those whose professional activities are not related to installation local networks. In this collection we have tried to collect all the information that will reveal as much as possible this topic, starting from the necessary tools and ending with various crimping schemes.

What will you need for crimping?

When choosing a crimper, you should pay attention to the following points:

1. The tool must be quite massive. Light pliers, as a rule, do not have sufficient strength and quickly fail. On the other hand, a heavy tool will cause fatigue quickly.
2. Halves of a tong press should not be bent (displaced) relative to each other. The slightest displacement leads to breakage of the connector during crimping.
3. Ergonomics, the tool should be convenient.

The advantage of this tool is that when removing the outer insulation, the coating of the wires is not damaged. Please note that the stripper is not allowed to cut an FTP cable (having a foil screen, that is, shielded).

As a rule, simple models with a minimum set of functions consist of two blocks: main and remote, the accepted designation in English is master and remote, respectively. Each block has LEDs numbered 1 to 8 and a ground wire G.

Testing is carried out as follows:

• The cable under test is connected to the main and remote modules.
• If the conductor is intact, the corresponding indicator lights up green; if there is a break, the LEDs do not light up; if the pairs are reversed or there is a short circuit, the color red is displayed. Some devices, in addition to light indication, can also provide tonal signals.
• Cross crimping tool, used when connecting sockets, patch panels, etc. It is not used for cable crimping; we have included it because it is included in standard kits for cutting twisted pair cables.

Actually, universal pliers will be sufficient for crimping, but it is more convenient to remove the insulation with a stripper, and use a tester to test the correctness of the wiring.

On the Internet you can find a description of how to crimp connectors using a flat-head screwdriver. This is indeed possible as a last resort when a crimper is not available. The quality of such a connection will be unreliable, so as soon as possible it is necessary to clamp the cable using pliers.

Crimping sequence for 8-core twisted pair + circuit

There are two standards for crimping 8-core twisted pair cables: T568A and T568B. Below is the accepted pinout for these standards.

Now let's move on to the process of crimping the UTP cable. The sequence of actions is as follows:

Screwdriver crimping

We will briefly talk about this method, although we do not recommend using it, but if there is no tool, then this option may be the only alternative. If we take the instructions described above as a basis, then it will be changed only in the fourth paragraph. Using a flat screwdriver we press the knives into the connector (8 pieces).

Then we clamp the plastic tongue that secures the cable. We recommend preparing several connectors for this process; as practice shows, without experience, breaking the connector during the “barbaric” crimping process is easy.

Twisted pair with 4 cores: crimping rules + diagram

A twisted pair of 8 cores is used for a gigabit network; if a 100 Mbit LAN is planned, then 4 cores will be sufficient. In such cases, the connector uses contacts “1”, “2”, “3”, “6”. Below are three possible pinout options for a 4-core twisted pair cable.

Crimping and cutting are carried out according to the same principle as for a 4-pair cable.

Straight and cross crimp

Now let's move on to crimping options. They come in two types:

1. Straight, that is, both ends of the twisted pair are crimped according to the same standard.
2. Cross, in this case one of the ends is crimped according to the T568A standard, the second - T568B.

Figure 12. Direct (A) and crossover (B) connection

This specificity is related to the connection diagram. There are actually three options:

1. Router-router. In this case, a cross line connects two routers or hubs.
2. PC-PC. Everything is clear here, network cable is used for direct connection two personal computers.
3. Router-PC. That is, Personal Computer connected to a network node.

Let's take a quick look at the listed connection diagrams.

Crimping twisted pair cables according to the router-to-router scheme

With this connection option, it is necessary to use a direct circuit (see A in Fig. 12). But, when using smart nodes in the network topology, this restriction does not have to be observed. That is, direct and cross connection schemes are allowed, since the router is able to recognize its type. But, it is considered correct to adhere to the selected standard for a particular LAN.

Crimping twisted pair cables according to the computer-to-computer circuit

A completely different situation arises when PCs are connected to each other. In this case, only a crossover circuit can work. This type connection was demonstrated in Figure 12(B).

Crimping twisted pair according to the router-computer circuit

This type of connection is usually performed in a direct manner. For smart switches (switches), this condition is not necessary, but nevertheless, it is considered “good form” to adhere to this condition.

Let's sum it up

In this collection, we have collected all the necessary information, thanks to which it will not be difficult to crimp a twisted pair cable for one or another connection scheme with your own hands, using the necessary tools. The main thing is to adhere to the basic rules; it wouldn’t hurt to repeat them again:

1. The crimping must be done in accordance with the color scheme.
2. It is important to follow the cable cutting rules. Let us remind you that the wires must rest against the stop of the channels. The clamp must secure the cable without removing the insulation (see Fig. 8).
3. The crimping procedure allows for direct and reverse methods, but it is unacceptable to connect a four-wire and two-wire connection circuit.
4. Although smart hubs allow you to combine direct and cross-connection methods, it is recommended to stick to one type of standard.
5. Checking the cable with a tester allows you to quickly detect the problem.
6. A high-quality tool guarantees an appropriate result. You can also purchase Chinese crimpers, but in this case the quality of crimping and the service life of the tool will be up to the manufacturer.

Read related articles on the website:

Laying and crimping a network cable is not a difficult task, but it is necessary. Although wireless network are gaining more and more supporters, they have disadvantages that are absent in the cable network:

Options/Media	Cable network	Wireless
Interference immunity	Yes	No
Transfer of Jumbo frames (large data packets, 9 or 16 KB in size)	Yes	No
Reliable protection against data interception	Yes	No
Protection against unauthorized access	Yes	Only under the conditions of using passwords and encryption
Price of personal computer hardware	Low	Average
Maximum throughput	1 Gb/s for Category 6 twisted pair	600 Mb/s at standard frequency

A two-pair cable consists of four copper cores (which are stranded in pairs and, in addition, the pairs are intertwined with each other), united by a polyvinyl chloride braid.

On a note! Copper conductors are intertwined to reduce the effects of electrical noise. This is especially true if the network cable is laid in close proximity to the power cable (220 V). Data is transmitted as a potential difference across two conductors. Provided that electrical interference acts uniformly on the entire network cable, then the potential difference between two copper conductors on an arbitrary section of the cable is the same. The pairs are intertwined to eliminate crosstalk (when the signal in one pair causes interference in the other).

Inside the braid, in addition to the copper conductors, there is a breaking thread (usually nylon). This thread can perform two functions:

1. Cutting the outer braid of the cable without damaging the braid of each individual core.
2. Increased tensile strength of the laid cable.

When choosing a cable, pay attention to the color of its protective braiding:

1. Gray color – the cable is intended for internal installation.
2. Black color - the cable is intended for external installation (as a rule, it has an additional core made of polyvinyl chloride or polypropylene).
3. Orange color - for internal lining; the braid is made of non-flammable material.

To make a patch cord, prepare the following materials and tools:

1. Cable of the length you need.
2. 8p8c (8 position, 8 contact) plugs, which are often mistakenly called RJ-45.
3. A crimping tool (crimper, pliers, crimper), a thin flat-head screwdriver, or a knife with a thin, non-fragile blade.

This is interesting! Error in names 8p8 cAndR.J.-45 is that the first is the connectors and plugs, and the second is the name of the standard by which they are made. By analogy, you can call canned stewed meat not “stew”, but according to GOST 32125-2013.

Making a patch cord

Step 1. Purchase and prepare a piece of twisted pair cable of the length you need.

On a note! It is recommended to leave some "allowance". This will allow you not to be afraid of an incorrect one, followed by “biting off” a damaged plug. In addition, a supply of cable will give you some mobility for your workplace. A tensioned cable is much easier to damage, despite its high tensile strength. Remember, twisted pair, as opposed to power lines, when rolled into a coil, does not cause interference and does not lose either the quality or speed of signal transmission.

Step 2. Remove a small portion of the outer braid, about two to three centimeters. Try not to touch the inner braid (braid of an individual core). If you use a crimper as a tool, use the appropriate connector for the knife.

Do not forget about the breaking thread when working without a special tool - this best way remove the braid without risking the cable.

Sometimes, when purchasing a category 5 cable, there may be no breaking thread inside; in this situation, use side cutters, wire cutters, or an ordinary knife.

Step 3. Place the conductors into the desired contacts of the plug. Remember that to work on the network you should use switching equipment with normal/uplink technology (currently any switch or network adapter computer for a 100 Mb/s network), in this case you will only need direct cable routing (identical conductors in identical contacts).

When using old equipment, you will have to do crossover (crossover, cross-link) wiring (one end of the patch cord is crimped in a straight wiring, the other in a crossover), as shown in the figure below.

On a note! Of course, the plug does not distinguish colors; data exchange only implies correct installation sequences of copper wires. Make sure that the conductors fall into contacts numbered 1, 2, 3, 6.

Step 4. Bite off the ends of the cores so that they are the same length, then insert them into the 8p8c sleeve to the extreme position (the cores should rest against the edge of the connector).

Step 5. Using a special pliers connector, “bite through” the copper conductors with the contacts of the sleeve.

On a note! Note, originally designed for four-pair cables, so the braid of a two-pair cable may not be securely fixed. That is why it is important to insert the wires all the way so that their position is fixed by the biting contacts of the connector.

Important! When selecting a crimping tool, pay attention to the location of the crimping knives. When using the crimper, they should rise evenly, and not along a radius. The tool itself must be heavy - this is an additional guarantee of the quality of the material; in addition, the lighter the crimper, the faster it will fail (the springs will become loose, the knives will loosen, or be damaged if dropped). If you have to crimp frequently, pay attention to the material of the handle - it is advisable that it be rubberized so that it does not slip in your hands. The last recommendation is to choose pliers with the ability to crimp different connectors (8p, 6 p, 4 p) – this will save you time and money.

You can do without using crimping pliers - with a thin flat screwdriver or a knife. You need to press the tip of the plug on the contacts until they bite through the copper conductors.

Important! Remember, you only have one attempt per plug, so it's worth having a reserve on hand.

After securing the conductors, press down on the braid lock.

This is interesting! Cable connection technology by cutting through the outer and inner braid was developed to extend the length of thick coaxial cable. The device for splicing individual pieces of cable is called a “transceiver” or “vampire,” and the method itself is called a “vampire tooth.” When connecting, two short teeth were used to bite through the shielding braid, and a long one was used to “bite” into the cable core.

Step 6. Upon completion of work, do not forget to check the quality of the created patch cord. The easiest way is to use a switch - connect the crimped connectors into the device sockets, and make sure that the LEDs indicate the fact of the physical connection.

Video - Crimping twisted pair, 4 cores

Conclusion

We examined the nuances of carrying out crimping work using a four-core cable. remember, that this method will allow you to save money when laying cable, but it should be used in networks with data transfer speeds of up to 100 Mb/s, since gigabit networks use eight conductors to operate.

When creating megabit LANs, a twisted pair cable with 4 cores is used. The bandwidth and number of wires of this type of cable is sufficient for patch cords for 10 or 100 Megabit networks. Working with cables during network installation, in addition to laying, includes crimping the twisted pair. In addition to the necessary tools when crimping, a specialist is required to be precise and accurate.

Twisted pair crimp circuit

The creation of cable LANs is regulated by the EIA/TIA-568 standard. There are two ways to crimp twisted pair 4 cores- straight and cross (cross). If the cable will connect the system unit of a desktop computer and a router (switch), then direct crimping is used - the conductors are located in the same order at both ends of the cable.

When connecting two routers or computers, cross-crimping is used, in which the conductors at opposite ends of the cable are swapped in pairs - plain and striped. When crimping, 1, 2, 3 and 6 cores are used. It doesn’t matter what color to attach to the contact number, the main thing is to follow the order when doing cross or direct crimping.

Required Tools

To perform the crimping operation of a 4-core cable, you will need the following tools and parts::

1. Directly the twisted pair itself is 4 cores, the crimping of which will be performed;
2. Two RJ-45 connectors;
3. Special pliers (crimper) with an “8P” socket;
4. Stripper knife or any other suitable cutting tool.

To control the quality and correctness of crimping, it is worth purchasing a tester that will allow you to determine whether the wires are mixed up when crimping the connector and whether the crimping is reliable.

Cable crimping process

When all necessary materials and the tools are prepared, You can proceed directly to crimping a twisted pair with 4 cores:

In case of twisted pair crimping 4 cores the indication must correspond to 1, 2, 3 and 6 channels of the tester. The absence of a light reaction to other contacts is a normal phenomenon, since the connection was made only to the above contacts.

If you don't have a crimper, you can use a screwdriver for connecting the cores to the connector. Preparatory stage in this case the same as with the crimper. It is necessary to carefully remove the outer insulation from the cable, separate the cores and trim the ends strictly at an angle of 90 degrees to the cable axis. After this, the veins are inserted into the connector along the corresponding grooves, and each wire is pressed using a screwdriver. Such a connection will work, but the quality of crimping will naturally be inferior to that of a crimper.

Crimp twisted pair Almost every user can use 4 cores without calling a specialist. You just need to follow the correct procedure and connect the wires to the contacts, depending on the purpose of the patch cord. When connecting a computer to a switch - direct crimping, and when connecting devices of the same name (computer-computer or switch-switch) - cross-type.

I decided to drop the cable from the router to the computer. I bought cable channels three years ago, but I just got around to them :). I don’t remember the last time I crimped an RJ-45, I remembered it and thought a lot. I'm sharing.

What do we need?

Select a cable and lay it

Measure from point A to B how much cable you need. Immediately figure out how it will go in the cable channel or be attached to the walls. Perhaps you are going to hide it under the baseboard. Before laying it is advisable to ring the cable :).

Before the “crimping” operation, the cable must already be laid, leaving an adequate margin at the ends. For example, it would be desirable that a computer with a cable connected could be pulled out of a niche, unfolded, and some kind of maintenance performed system unit without the need to disconnect wires.

Cables for laying the network are used with 2 and 4 twisted pairs of wires. Any of them will suit you, but 4-wire (with only 2 pairs) will allow you to connect only at speeds of up to 100 Mbit. Such a cable is cheaper, easier to crimp, and often higher speed is not required.

Please note that each pair of cores is marked with its own color. For example, an orange wire is intertwined with a white-orange one. Each pair is absolutely no different from the other, except for the color of the insulation. Wire connection and crimping diagrams always specify the colors of the wires, but in fact, if you swap two pairs, everything will work exactly the same.

RJ-45 connectors

Through the transparent body of the connector, 8 gold-plated contacts are visible. The numbering of contacts from 1 to 8 is shown in the picture.

For crimping we only need a pair of these connectors. But it never hurts to take a few in reserve. :)

Crimping pliers

The figure shows three typical operations that crimping pliers can perform.

Stripping the overall cable insulation. The knives (1) do not close completely, and the wire can be rested against a special strip. The bar will allow you to measure the optimal cable length (about 1.5 cm). When removing the insulation, the end of the cable can be turned, then the knives will cut off the protective layer in a circle.

Crimping RJ-45 connector. Pincers (2) are used at the very end, when the conductors are passed into the desired tubules. The serrated edge presses the contact blades into the conductors, and a special protrusion snaps the RJ-45 wire retainer into place.

Knife. The 3rd type crimping element is usually used for straightening conductors and cutting cables. This knife completely touches the opposite edge, working like a wire cutter.

What are we connecting?

There are two types of connections, so we need to figure out what we will connect. The most common case is when we connect a computer to some kind of switching device - a router, a switch, a switch... A direct connection diagram is suitable here ( work station- concentrator).

Direct connection diagram

You need to make exactly the same cable crimp on both ends according to this diagram. Choose a picture for your case - 8 or 4 wires in the cable.

The color order of the pairs is shown as an example. Instead of the orange pair, you can connect, for example, a green pair to pins 1 and 2. But both connectors must be routed equally at the ends of the wire.

Cross cable layout

The second case is the connection of two hubs or two workstations. In this circuit, you need the orange and green pairs at the ends of the wire to swap places.

Ten years ago home Internet was a rarity, now in cities almost everyone has it. Moreover, there is more than one device, so you have to create a fairly extensive network at home, run wires, install Internet sockets. Wires for the Internet are called twisted pair. They end with a special plug-connector. The process of connecting a cable to a connector is called “twisted pair crimping.” Let's talk further about what it is and how to do it yourself.

Twisted pair - special cable, which consists of one or more pairs copper wires in a protective shell, twisted together with a certain pitch. If there are several pairs in the cable, their twist pitch is different. This allows you to reduce the influence of conductors on each other. Twisted pair cable is used to create data networks (Internet). The cable is connected to devices through special connectors that are inserted into standardized equipment connectors.

Species and types

Twisted pair may or may not be secure. The protected pair has screens made of aluminum foil or braid. Protection can be general - for the cable - and pairwise - for each pair separately. For indoor installation, you can use an unshielded cable (UTP marking) or with a common foil shield (FTP). For outdoor installation, it is better to take it with an additional metal braid (SFTP). If along the route a twisted pair runs parallel to electrical cables, it makes sense to take a cable with protection for each pair (STP and S/STP). Thanks to the double shield, the length of such a cable can be more than 100 m.

Twisted pair is a cable that is used to connect wired Internet.

There is also multi-core and single-core twisted pair. Single-core wires bend worse, but have best characteristics(the signal can be transmitted over long distances) and tolerate crimping better. They are used when connecting Internet outlets. In this case, the cable is fixed during installation and then hardly bends.

Multicore twisted pair bends well, but has greater attenuation (the signal travels worse), it is easier to cut through when crimping, and it is more difficult to insert into the connector. It is used where flexibility is important - from an Internet outlet to an end device (computer, laptop, router).

Selecting a Category and Containment

And a few words about the color of the protective sheath and the shape of the cable. The most common type is gray twisted pair, but there is also orange (bright red). The first type is ordinary, the second is in a shell that does not support combustion. It makes sense to use non-flammable twisted pair in wooden houses (just in case), but there is no particular need for this.

The shape of a twisted pair cable can be round or flat. Round twisted pair is used almost everywhere, while flat twisted pair is only needed when laying on the floor. Although no one is stopping you from running it under the baseboard or in a special baseboard with.

Number of pairs

Basically, twisted pair is available in 2 pairs (4 wires) and 4 pairs (8 wires). According to modern standards, at speeds up to 100 Mb/s, you can use two-pair cables (four wires). At speeds from 100 Mb/s to 1 Gb/s, 4 pairs (eight wires) are needed.

It’s better to immediately take a cable with 8 wires...so that you don’t have to retighten

Currently, the data transfer speed for Internet connections for private houses and apartments does not exceed 100 Mb/sec, that is, you can use a twisted pair of 4 wires. But the situation is changing so quickly that there is no guarantee that in a few years the 100 Mbps threshold will be exceeded, which means that the cable will have to be pulled. In fact, there are already tariffs with speeds of 120 Mbit/sec and higher. So it’s better to pull 8 wires at once.

What is twisted pair crimping and how to do it

To connect to a peripheral device, the twisted pair ends with a specially shaped plug - a connector, into the grooves of which wires are inserted. These grooves end with copper contact plates, and approximately in the middle of their length, perpendicular to the plane of the plates, a metal plate with slots (knives) is installed. When a twisted pair is crimped, the inserted wires are pressed against the knives, they cut through the protective sheath of the wires, and they themselves are pressed tightly against the copper conductor, ensuring good contact.

At first glance, this connection method seems unreliable, but practice has shown that it is at least as good as high-quality soldering, and sometimes even more reliable, since the chances of damaging the insulation are minimal. But good contact is ensured only if standards are observed in the manufacture of connectors and twisted pairs.

To crimp twisted pair cables, you need special pliers with a socket for the connector. A connector with wires tucked into it is inserted into this socket, then the pliers are compressed until it stops. This completes the crimping of the twisted pair. This method is reliable, since the pliers develop a standard force, which is just necessary to cut through the insulation, but not enough to damage the conductors. Such crimping pliers (or crimpers) cost about $15-18. If you need to install several connectors, you can already think about purchasing such equipment. If you only need to terminate one piece of cable, you can try using a regular screwdriver or pliers.

When crimping a twisted pair with a screwdriver, each wire is separately pressed into the knife until the sheath is cut through. The method is not the most convenient - the screwdriver slips, it is difficult to check whether the sheath has been cut through, and there is no certainty that the wire is not damaged. But this method of crimping is also possible.

When crimping twisted pair cables with pliers, you need to be even more careful. We press the plate with the jaws, but since the shape of the pliers is not sharpened to fit the connector, it is easy to pinch the wires along the edges or break the housing. Therefore, we press little by little, on one side and the other. If the middle is not pressed through, take a screwdriver and straighten the wires with it.

Selecting a wire pinout diagram

As you might guess, the wires in the connector must be placed in a certain order. This order in the language of professionals is called “pinout”. In our country, two wire layouts are accepted: straight (568V) and cross-over (cross-over in Russian, designated 568A). Direct pinout is used when connecting a switch/hub/router to a computer or other device, cross pinout is used when connecting two computers directly. That is, we usually use a direct circuit, which is labeled 568B. The order of wires when crimping a twisted pair in this case is as in the photo.

If you look at this diagram, you will understand why it is called straight. Because if crimping a twisted pair is done with its help, the wires at both ends of the cord (if it is done) are located the same way.

The following diagram shows the cross pinout diagram of a twisted pair cable. The name is also clear - on the opposite side the wires are located in a different - inverted - order.

There is also a circuit for crimping a twisted pair into 4 cores (two-pair cable). Some of the tracks in the connector remain empty. But the order of actions does not change.

This connection method is only used to connect peripheral devices, so the diagram is only straight. Please note that on each diagram there are numbers from 1 to 8. They indicate the contact number. When laying wires in a connector or when connecting to a socket, look for numbers on the housing. They are extruded, but it is difficult to see them on transparent or white plastic. Having found the numbers 1 or 8, you know how to hold the connector and in what order to arrange the wires.

Twisted pair crimping procedure

Now about the process itself. When working, you must be careful not to damage the conductors or insulation in the wrong place. If there are no special tools for stripping the insulation, use a stationery or sharply sharpened kitchen knife. To avoid damaging the insulation, first cut it only a little, then bend the cable. Chalk is specially added to the polymer shell, which makes it brittle when broken. So the slightly cut insulation breaks when bent. This applies to stripping the cable sheath. You will also need to cut the conductors, there are no special tricks here - take the wire cutters and bite them off.

The procedure for crimping a twisted pair cable is as follows:

1. Carefully remove the insulation from the cable. We make a cut at a distance of about 15 mm from the edge, without trying to cut through the shell. Then we take the cable on both sides of the cut and bend it. The shell bursts at the cut site. It is necessary to change the bending direction a couple of times so that the insulation is completely separated. Then we simply pull the separated piece to the side; it comes off without much effort.

   

2. We straighten the conductors; if there is a screen, we twist it and bend it to the side. We lay out the wires in colors according to the required pattern. We pinch them between the thumb and forefinger, straighten them so that they are straight and go one next to the other.

   

3. We take wire cutters and cut the wires so that they stick out from the beginning of the insulation by 9-10 mm.

   

4. We take the RJ-45 connector, turn it with its “tail” down, and insert the wires into the grooves. This is perhaps the most difficult part. Without experience, they don’t want to get into their jobs.

   

5. We push the inserted wires forward until they stop. In this case, if you cut the wires correctly, the edge of the insulation rests against the mark on the connector. This is the type of crimping of the Internet cable that will work without problems. If it is not a sheathed cable that comes out of the connector, but insulated wires sticking out, problems may occur after a while and you will have to crimp the twisted pair again.

   

   “All the way” means that the wires reach the end of the grooves and the insulation rests against the side

6. We take the pliers, insert the connector into the socket (there is a specially shaped slot there, so you can’t go wrong), and squeeze the handles. This completes the crimping of the twisted pair.

   

   Crimping twisted pair, the last stage - press with pliers

Video on the topic

No matter how you describe the processes in words, it is better to see everything in action. Therefore, the video is worth watching to have a complete idea of ​​what you have to do and how. The next video shows how to crimp an Internet cable without special pliers.

The process of crimping a twisted pair into 4 cores is not too different from an eight-core one, but there are certain difficulties when trying to thread the wires into the desired grooves.

An Internet cable can end with more than just a connector. It can connect to an Internet outlet. You also need to connect a twisted pair cable to it and connect it.