We will not prove to you that twisting wires is a good way to connect. Yes, it can be qualitatively executed and insulated. Also, it is perfect as a temporary option. But according to the rules of electrical installations (PUE), in order to connect a wire or cable, ordinary twists are not recommended. Nevertheless, we will conduct a conversation about her, and very detailed. Firstly, because contrary to the PUE, most of the connections are carried out by this ancient "grandfather" method. Secondly, because the correct twisting is the main stage of the most reliable ways of connecting wires - welding and soldering.

Why do you need a good twist?

Imagine that two connected wires were twisted together just to be like. Those who are familiar with electrical engineering know that at the point of contact of the two conductors there is a transition resistance. Its value depends on two factors:

• surface area at the point of contact;
• the presence of an oxide film on the veins.

To perform twisting, the core is exposed, the metal interacts with atmospheric oxygen, as a result of which the surface of the conductor is covered with an oxide film, which has a decent value of resistivity.

example of poorly executed twisting: the twisting point is heated, the insulation melts

Accordingly, if the twisting is performed poorly, the transition resistance increases, which in turn, when the electric current passes through the junction, will cause heating. As a result, the twist site may become hot so that a fire occurs in the wiring. Surely everyone had to hear the phrase in their life that the fire occurred due to a malfunction in the electrical network.

To prevent this from happening, the contact connection of the wires should be as strong as possible, reliable and safe. That is, the twisting must be performed so qualitatively that the transition resistance is stable and does not change over time.

Preparing wires for twisting

Remember! Never twist while energizing, even if you have tools with insulated handles and dielectric gloves. First, turn off the power to the workplace by turning off the introductory machine to an apartment or house.

To get a good twist, the following steps must be followed exactly:

1. Strip the conductors to be connected from insulation, while avoiding damage to the metal surfaces of the conductors.
2. Dampen a clean cloth in white spirit or acetone and wipe the exposed areas of the veins from dirt.
3. Now use sandpaper to strip the cores to a metallic sheen.

Stranded wires

The twisting of stranded electrical wires can be performed in different ways.

Parallel twisting

The simplest method is parallel twisting, when both stripped wires cross over the cross on one another at the place of stripping the insulation and are simultaneously twisted. Such a connection gives a reliable contact, but it will not tolerate the applied force to break and vibration.

This method is best used for copper wires, when one of them is monolithic, and the other is multicore. The monolithic wire must be stripped from insulation a little more than stranded. After twisting from the remaining copper monolithic tail, an additional bend is made in the direction of twisting, due to this, the connection is more reliable. This method is also suitable for twisting aluminum conductors with different cross sections.

The advantage of parallel twisting is that it can be used to connect more than two wires at the same time.

Sequential twist

In a sequential method, each connected wiring is wound onto another. Reliability and contact with such a connection will be optimal, but this twist can be applied only for two wires, no more.

The stripped veins fold cross-wise onto each other approximately in the middle of the bare section and begin to twist. One wire goes around another wire, just wrap the second wire around the first one.

Bandage twisting

Stranded wires can be interconnected by the method of bandage twisting. In this case, the connected conductors are stripped to the same length and applied parallel to each other. In this position, they are fixed by a third wire, which is tightly wound on the exposed surface of the connected cores.

Please note that with this twist you can connect rigid stranded wires, but as a fixing wire, you must definitely use a soft (flexible) wire. The denser you make the winding of the fixing wire, the more reliable the contact connection will be.

With the help of banding twist, more than two conductors can be connected.

Single wire

All of the above methods of twisting stranded wires can be used for single-core. But it is best to use a parallel connection in this case.

Remember the most important thing, before connecting single-core wires, the insulating layer on them should be cleaned only along the conductor at an angle. This is especially true for aluminum conductors. If you pass a knife at an angle of 90 degrees in a circle of the conductor, the insulation, of course, will be removed. But in further work, with the slightest movements in the place of the incision, the conductor will go to break over time and, ultimately, the core will break.

Strip the insulating layer on the connected cores 3-4 cm. Lay the wires on top of each other at an angle of 45 degrees, but not in the place of the bare cores, but 1.5-2 cm higher from the place where the insulation was cut. Hold this place firmly with your left hand, start twisting both wires with your right hand. First, they will be twisted together with the insulating layer, then the connection of purely bare veins will already go.

No matter how strong your hands are, at the end be sure to finish twisting with pliers, especially this again applies to aluminum wires.

Another important tip! After you make a twist, do not rush to isolate it. Let the electrical circuit run for several hours, then turn off the introductory machine to the apartment and check the temperature at the point of twisting. If the node is hot, it means that the contact connection turned out to be unreliable and it is better to redo it. If heating is not detected, then the twisting is performed qualitatively, can insulate it.

If you need to perform a large number of twists, you can use a screwdriver with a homemade fixture, as shown in the video below:

Methods of isolation of twists

To make a twist of wires is another half of the job, it is very important to qualitatively perform the insulation of this place. There are three ways to insulate a made electrical unit: using insulation tape, heat-shrinkable tubing, and PPE caps. Let's consider each of them in more detail.

Insulating tape

Insulation tape is a special material whose main purpose is to isolate the junction of electrical cables and wires. No matter what modern technologies appear, it is hardly possible to meet an electrician who would not have a roll of electrical tape in his pocket. This is the most common and inexpensive insulating material.

There are a lot of varieties of it. Tapes are made on the basis of mica and fiberglass, polyester and epoxy films, acetate fabric and paper. To isolate the twist in the household electrical network, we recommend using a PVC tape (polyvinyl chloride is used in its basis). For its manufacture, a polyvinyl chloride film is taken and glue is applied on top. The quality of the insulation tape itself, as well as the reliability of the insulated joint, depends on the quality of these two components.

Insulating tape is considered to be the best, for the manufacture of which glue is used on a rubber base and PVC film of class A. This material is characterized by such positive qualities as:

1. High adhesion (adhesion of dissimilar surfaces).
2. Increased elasticity (perfectly stretches and glues).

So be sure to consider this when buying electrical tape.

The insulation tape should be wound on a twisted section in at least two layers. Start winding 2-3 cm above the bare twist, the tape should be applied over the insulation of the wire. This will allow to achieve maximum tightness and insulating reliability, protect the contact connection from moisture. Next, wind a little at an angle, moving to the end of the twist. Having reached the end, bend the electrical tape around the tip of the twist and continue winding now in the opposite direction. Having reached the place where they started winding, cut the insulation tape with a knife. For efficiency, you can repeat the same thing again and make insulation in four layers.

Thermotube

A heat-shrinkable tube (abbreviated as HER) is made of thermopolymer materials, which, under the influence of hot air, water or elevated temperature, can change their geometrical shape and dimensions (shrink or expand).

The main advantage of thermotubes is that they can be mounted on objects with a complex profile, which is exactly what the twist of the wires has. The heat-shrinkable tube provides excellent electrical insulation and protects against mechanical damage. Tubes are produced in different diameters. The material from which they are made does not support combustion and is not toxic.

Industrial heaters are used to heat the tubes. This tool is not cheap and buying it just to insulate splicing of wires is not economically viable. Therefore, in everyday conditions, they often use an ordinary hairdryer or a lighter.

It is important to remember that with this method of insulation, the heat-shrinkable tube must be put on one connected wire in advance (before twisting).

Cut the tube with a margin, when it is put on a bare section, it should protrude at least 1 cm on the insulating layer of the conductor.

When the connection of the electrical wires by twisting is completed, pull the tube to this place. Direct a heat gun or lighter flame at it, under the influence of hot air the tube will instantly decrease in size and tightly compress the insulated area. Reliable, fast and inexpensive way.

Keep in mind that connected wires that are thermally insulated can be used for laying in the ground or when immersed in water. This insulating material is recommended for use on the street, in baths and bathrooms, as it will reliably protect the place of twisting from moisture.

How to choose to use a shrink tube is shown in this video:

PPE caps

When installing wiring in an apartment or a house, isolation caps can be used with PPE caps (connecting insulating clamp).

In this case, it is enough to make only a high-quality twist, without soldering. The tip must be cut off and put on with the effort of PPE, the crimping springs inside the cap will expand and tightly wrap around the connected assembly. For a better fit to the joint surface, rotate the cap clockwise.

Now you know how to twist the wires correctly, which material is better to choose to isolate the junction. From the article it is clear that to perform twisting it is not necessary to be a professional electrician, such work is within the reach of anyone who knows how to hold pliers in their hands. Just do not forget that twisting is only an important stage that must be completed by welding or soldering.

One of the fastest and at the same time the most unreliable ways of splicing wires is twisting the wires. It is popular because it does not require special devices, and only an insulating tape is needed to close the junction. No need to have special skills, just know the most common types of twists. However, this method is not without drawbacks.

Why twisting is the main advantage

If you need to connect two copper wires together, they can be soldered. But not everyone has this useful skill, and a soldering iron may not be at hand, for example, if a cable break in the power tool or wire in the junction box in the country. Therefore, such a property of copper and aluminum conductors as flexibility is very convenient - they can simply be folded together and twisted in neat turns. In this case, even pliers will not be needed if the metal cores of the wires have a small diameter. This concerns not only, but also a television cable, antenna, telephone and many others, including computer ones.

Another advantage is the relatively high quality of the connection without soldering. If the wire is used to transmit a signal, interference due to twisting usually does not appear, and if it does, then in very rare cases. It is very important that such a connection saves time, and sometimes money. In particular, there is no need to wait until the soldering iron warms up or equip a special welding inverter for wires, it is not necessary to tin every core.

If the cores are varnished and do not provide contact, they can simply be scorched with a match or a lighter.

Very thin veins when burned easily burn out or become brittle, which can already be attributed to disadvantages.

What you need to know - the nuances of using twists and their disadvantages

So, we mentioned some of the difficulties of working with very thin, varnished copper cores. Without stripping, they will not give contact, but just scorching with an open flame means burning the wire. However, with thick veins, it is not always possible to easily cope with conventional splicing. For example, aluminum is quite brittle and too many turns result in microcracks that cause the twisted ends to simply break. About the same thing happens in severe frost with a copper core - with a strong tightening of the turns, they burst.

There are directly opposite nuances, in particular, concerning insufficiently tight twisting of the ends of the wire. Each time, connecting the cores of two cables by twisting, you need to connect the power without insulation and after 30-40 minutes to check if the core is heating up. The fact is that with a loose contact of the conductors, an increased resistance arises and the junction starts to heat up quickly, which can lead to burnout of the splice of the wires. It should be borne in mind that due to temperature changes, the twist of the wires weakens over time and still starts to warm up.

In order to connect the bare ends of the wire, it is enough to twist them with your fingers, but it is recommended to use pliers to create high-quality tight turns.

It is extremely undesirable to interconnect conductors of two different metals, for example, aluminum and copper, but if there is no other option, you should use a special terminal, caps or pads. We also avoid splicing a single-core wire with a multi-core one, since they have different resistances, and with the same diameter they are designed for different loads. If you still have to resort to such a connection, calculate the peak power of the current that will pass through the conductors at maximum load. It should be within the tolerance for a weaker wire.

Existing types of twists - a list of frequently used

There are dozens of single-conductor and multicore cables interlacing each other. It is extremely important to know that you must always connect the same type of wire, or use special electrical junction boxes with terminals or screw terminals. The same devices easily combine cores of different metals. As for the twists, they distinguish between parallel, sequential and branches. The difference between them in the location of the conductors relative to each other. In the first case, the ends are placed side by side, in the second they are reduced to each other, and in the latter case we attach the conductor perpendicular to the bare section.

As for the method of splicing, there can be quite a lot of scope for action. So, for example, multicore cables can be pre-twisted at the ends and you will correctly twist the wires as if you had single-core cores in your hands. But it’s better to splicing in a sequential way, after having previously split the cores at both ends and then weaving them in opposite directions. Wires that have one core each can be twisted in a simple way, by a groove or bandage. We will analyze each of them in more detail.

We twist a stranded wire - the best option

As already mentioned, if there are no terminals, we use twisting, but the main condition for any multicore cable is the maximum contact of all conductors at the junction. Therefore, having exposed the ends, we twist each of them at the base, a quarter of the length from the insulation, and then we part with a whisk. We do this with each wire, usually you need to do 2 twists of electrical wires to get plus and minus (or zero and phase), less often 3 - if there is another phase or ground.

For a serial connection, we carefully bring the beams together in an opposite motion so that the corollas enter one another and the wiring intersects, even at different arbitrary angles. Next, we begin to twist the cores of one end from ourselves, and the other to ourselves, if you look at the cables from the side. In general, they will be curled in one direction, clockwise, if you look at each corolla from the connection point.

A parallel connection of electrical wires is performed in much the same way, only the ends with the separated bundles of cores are brought to each other at a small angle from the side, until they intersect. After receiving the desired contact, we simply weave all the wires into one thick pigtail. Then, of course, it is desirable to fill the resulting twist with tin, having previously tinned, but if there is no such possibility, it is possible to wind the insulation, be sure to at least 2 layers. For this purpose, special tubes are also used, worn on the wire before connection.

We connect wires with one core - effective ways

A simple parallel option is the fastest. All that is needed is to connect two wires that need to be twisted together at a certain angle, and then twist them with even turns from the point of intersection. To make a serial connection, you need to slightly bend the bare ends of the wires, reduce them in an oncoming motion to cross. After that, each one is wrapped around the base of the other, one from itself, and the second from itself, if you look at the cable from the side.

Parallel fastening with a groove is performed by curling one conductor around the other at two points - at the base of the stripped core, closer to the insulation, and near its end, previously slightly bent. This method gives a fairly smooth and durable installation, consisting, in fact, of two twists. Serial connection is already carried out by mutual braiding bent at the ends of the cores with the passage of a small area. Again, you get two twists near the isolation itself.

The bandage is done in cases where the wires are too thick and do not lend themselves well to twisting together. In this situation, the wires are stripped of insulation and bent at the ends by 90 degrees, after which they are connected together in parallel or in series. Then a thinner core is taken, moreover, it is also obligatory from a wire with one core, and is wrapped in even turns around mounted sections. Then insulation is applied.

The connection of the three wires is no different, you just need to add the third core to one of the first two in a parallel way, and then connect to each other by any of the above options. The same applies to the dump. The difference in connecting the side conductor to the exposed area is only that only it will be wrapped in turns, and the main wire will serve as the basis. All of the above methods are suitable, including the bandage in the situation when the core of the attached cable has too large a diameter.

Whatever they say about the process and methods of twisting wires - this method remains very relevant to this day and will remain for long times. Why is that? Consider this topic in more detail. With this method of connecting electrical conductors, there are a large number of nuances, advantages and disadvantages, including a ban on performing such operations under the rules of the PUE. However, it is worth noting that the connection of twisted wires is most often used. There are many reasons, consider the most common.

Firstly, twisted joints are often used when performing “rough” installation. This is due to the fact that during the initial work the main goal is to check the operability of the laid nodes. The presence of a signal / voltage is checked (depending on the type of manipulation), additional work is carried out on the secondary wiring of additional elements, device contacts are displayed, such as:

• switches of various types;
• built-in voltage stabilizers;
• built-in voltage converters;
• built-in step-up / step-up transformers;
• ordinary sockets;
• Smart sockets;
• power consumption monitoring devices;
• specialized sockets with special outputs (RJ-45, for example).

After conducting a “rough” installation, it is extremely important to check the operability of the above devices. And in the case of their incorrect operation or lack of electricity / signal, you have to re-deal with a certain section of the circuit or again conduct wiring operations and fix the malfunctions.

Secondly - this type of contact of the conductors allows you to quickly restore the working capacity of the site and get the necessary electricity / signal for certain manipulations. In the future, depending on which devices will be connected to this section, it will be possible:

• leave twisted;
• improve connection;
• replace this site with another, with other connecting elements.

Thirdly - for the twisting of wires do not require any special tools. Such manipulations can even be performed “in the field”, provided that “gluttonous” electrical appliances are not connected to the created site.

It is worth noting that twisted wires can provide a fairly reliable contact for a long time, subject to all necessary instructions and the correct execution of the work.

So, it is wise to take into account the situation if you decide to resort to such a connecting method as twisting. It is mandatory to take into account the connected load, the selection of the optimal wire section and further calculation of the circuit in case of changes in the quantity or power of consumers.

Advantages and disadvantages

The interweaving of wires among themselves is probably the oldest way of merging conductors among themselves. However, over time, the power of devices requiring high currents grows. Twisting, as a rule, is not designed for them, but within the framework of home use is very appropriate.

It is worth mentioning that this type of wiring cannot be used with such devices as electric kettles, refrigerators, washing machines, heaters and fan heaters, electric stoves, computers.

The main advantages of twisting are:

• speed of creation;
• durability (if performed correctly);
• the possibility of twisting wires without additional tools;
• ideal for signal contact (in the absence of connection of high-current consumers);
• the ability to improve the connection by soldering;
• cheapness;
• the ability to combine two, three, four wires simultaneously;
• the ability to reconnect.

Its disadvantages include the following:

• the need for isolation;
• operability only with low-current consumers;
• inconvenience of installation;
• fire hazard due to improper performance of work;
• a large number of nuances that MUST be considered when braiding wires;
• "Surge" voltage and interference with electrical appliances when overloading the site.

As you can see above, twisting has a limited range of use, it cannot be used with powerful devices, and when used with computers, modern TVs, sound equipment and other equipment of the 21st century, there is a problem with the occurrence of pickups and “throws”. Therefore, it is advisable to perform the braiding of wires when used with light devices (chandeliers, lamps, and so on), power adapters, and other "weak" devices.

Nuances

Connection of conductors from different materials

The most basic is that it is FORBIDDEN to twist with conductors of different materials. IT IS FORBIDDEN to weave copper and aluminum wires. This is due to the fact that when copper and aluminum come into contact, a galvanic pair appears, which destroys the created compound. The higher the current passing through the plexus, the faster its destruction will occur. Such contact of wires threatens with the following consequences:

• heating, sparking and subsequent ignition;
• deterioration in the quality of contact of such a "gossip";
• reduction of the area of \u200b\u200bcontact;
• strong heating of the wires at the plexus;
• rapid oxidation;
• under temporary and powerful load, heating-cooling cycles occur, which is fraught with strong
• deterioration in the quality of the connection.

The appearance of an oxide film

The film appears as a result of the interaction of the oxygen atmosphere of the air and the conductor. The metal conductors used to create the compounds are usually made of aluminum or copper and suffer quite a lot from the oxide film in the absence of insulation of the compound. More expensive materials, rarely used in electrical circuits, such as gold and platinum, are free from this drawback, but their cost is extremely high. Oxide film on wires threatens with the following consequences:

• deterioration of twist contact quality;
• intensification of the heating process with the passage of current.

To deal with this drawback is quite simple - it is necessary to conduct high-quality insulation of the twist.

Transition contact resistance

This resistance appears as a result of poor contact between the wires, which is why the temperature rises sharply at the point where the current passes from one part to another. Transient contact resistance serves as a catalyst for the rapid destruction of the plexus of wires, especially in the absence of insulation. To minimize the transient contact resistance, make the most tight contact between the two conductors.

Types of twists and joints of this type

One of the advantages of such a connection as twisting is the possibility of improving it by soldering or welding. When soldering, the connection becomes strong and is able to withstand high currents, while welding, special equipment is used, it allows you to give strength to the completed connection. Soldering and welding of both copper and aluminum wires is an excellent way to improve its characteristics: reduce the heat load by improving the contact at the places of welding or soldering.

During the work, twisting can be divided into several types depending on the materials, type of wire, type of twisting. It is imperative that the cross-sectional area of \u200b\u200beach of the conductors is consistent with each other, as well as suitable for the load used.

Conductors can be made of the following materials:

• aluminum;
• copper.

Aluminum braiding is less resistant to further unwinding, while copper conductors can be braided and braided several times, for example, to add a third pin. Aluminum withstands 1-2 times the load on twisting-unwinding, copper - 3-4 times, you can twist-unwind without any damage.

In this case, the conductors can be divided into 2 types:

When performing the twisting process, it is worth considering the type of conductor, since the options for plexus can be different. Depending on the type of wire, one or another method of twisting should be used.

A cord with a monolithic core is usually used with a stationary location of the wiring, then when there is no need to move the equipment. Stranded conductors are often used for “rough” installation or where there is a need to move devices.

The twisting of both copper wires and aluminum wires is the same and is given in the tables for each type of cord (multi-core / single-core). If it is necessary to weave more than two conductors, for example 3-4, then first the initial twisting for the two ends (shaping the connection) is performed - 1-2 turns, after which the required number of conductors and their twisting in one or another pattern are added.

It is allowed to bind two conductors of different types (multi-core / single-core), however, it is important to take into account the cross-sectional area of \u200b\u200beach conductor.

Twist ourselves

In professional installation, special clamps are used to make the connection - SIZ (connecting insulating clamp), with their use, the final twist is allowed from the point of view of the PUE, but it is worth remembering that such a device is not designed for high currents.

So, how to twist the wires at home? To perform this manipulation it is necessary:

• take into account all the nuances in advance (location, load of connected equipment, and so on);
• to get the necessary tools (pliers, knife, sandpaper, heat shrink, it is desirable to have a hot air gun and a device for removing insulation, screwdriver if available).

Consider the situation with weaving from a cord with a monolithic core:

1. It is necessary to strip the ends of each wire 3-4 cm using a special tool (stripper) or a construction knife. It is extremely important to remove the insulation and not leave deep cuts on the core.
2. Then we put heat shrink on one of the ends.
3. Then degrease the cleaned surfaces with alcohol / acetone / white spirit.
4. Then, taking sandpaper, we clean the wires of the wires.
5. We lay the veins parallel to each other, hold with pliers.
6. We carry out weaving (in accordance with the scheme) clockwise, at least 5 turns for one core. The cores should fit snugly together.
7. We shift the heat shrink to the place of contact and heat it with a hairdryer or a lighter. It is important that the shrink tightly "took" at the place of twisting.

It is allowed to hold one end of the cord with a screwdriver and slowly rotate it, while the other end is woven into a rotating end, creating tension by hands, thereby making the connection more tight.

With a multicore cord, the situation is slightly different:

1. We clean the ends of each wire 3-4 cm with a special tool (stripper) or a construction knife. It is imperative to carefully remove the insulation and not damage / cut the cores of the cord.
2. We put heat shrink on one end of the cord.
3. Dissolve the veins of each cords into small "pigtails".
4. Degrease the obtained “pigtails” with alcohol / acetone and so on.
5. We impose veins on each other from each cord between each other.
6. We weave together, making the connection tight (at least 5-6 turns per pigtail).
7. We shift the heat shrink to the place of twisting, warm up with a hairdryer / lighter. The heat shrink should sit tightly at the junction.

If it is necessary to create a “bundle” of mono-core and multi-core cords, the algorithm also changes, and it is highly desirable to weave using the “Branch” method:

1. We clean the ends of each wire 3-4 cm with a special tool (stripper) or a construction knife. Take care not to damage the cores of each of the cords.
2. We put heat shrink on one of the cords.
3. Degrease the cleaned areas with alcohol / acetone and so on.
4. We bend the single-core end by 180 degrees, so that he then presses the twist.
5. We twist the stranded cord around the single-stranded end in accordance with the scheme (clockwise), at least 5-6 turns, the more the better.
6. We clamp the bent end of the single-core wire in advance and press it to the twist made with pliers.
7. We shift the heat shrink to the place of contact, warm up with a hairdryer / lighter. We make sure that the heat shrink is well fixed at the twist.

Related videos

In the process of installing electrical wiring, especially in residential premises, it is necessary to apply the technology of connecting wires and cables. This process requires some skills and knowledge. After all, improper connection can lead to irreversible processes. A malfunction of the general power supply, as well as fires, may occur. The fact is that a carelessly made connection of stranded wires can cause a fire, which in turn leads to a threat to human life and health. Requirements for the installation of wiring in residential buildings are spelled out in the Rules for Electrical Installation, in short - PUE. PUE permits the use in residential premises of electrical wiring made only with copper wires. The connection of multicore and single-core wires is allowed only by crimping, welding, soldering or using crimps. In squeezes, the connection is made mechanically, using screws or bolts and clamps.

Various twist options

Unprofessional connection. This is a twist of a stranded wire with a single core. This type of connection is not provided for by the rules, and if such a connection of wires is detected by the selection committee, then the facility simply will not be accepted for operation.

The twisting of a stranded copper wire in a steamed box is used as an intermediate operation before soldering or welding the joint, and it is necessary to solder or make crimp connections.

However, twisting is still used and here you need to know how the correct twisting of stranded wires is performed. It is often used in emergency cases when it is not possible to professionally make a connection, and the life of such a connection will be short. And yet, twisting can only be temporarily applied to open postings, so that you can always inspect the junction.

Poor wire connection

There are several types of twists. When twisting, it is necessary to achieve good electrical contact, as well as creating mechanical tensile strength. Before proceeding to connect the wires, they should be prepared. Wire preparation is carried out in the following sequence:

• the insulation is removed from the wire at the junction. Insulation is removed so as not to damage the wire core. If an incision appears on the wire core, then in this place it may break;
• the bare spot of the wire is degreased. To do this, it is wiped with a cloth dipped in acetone;
• to create a good contact, the fat-free section of the wire is cleaned with sandpaper to a metallic luster;
• after connection, the insulation of the wire must be restored. An insulation tape or heat-shrinkable tube can be used for this.

In practice, several types of twists are used:

• other various connection options.

Details on methods of connecting single-core wires

Professional Connection

We will consider various options for reliable connection by technology: soldering, crimping, welding and terminal connection of wires. You will refuse from unreliable twisting when installing soldered boxes and other connections.

Soldering wires

The connection of copper stranded and single-core wires by soldering is one of the reliable methods. With such a connection, a good electrical contact is created, and the junction is mechanically resistant to tensile loads. This method can be used when: splicing two damaged wires, lengthening the wires, moving sockets or switches. The wires connected in this way can be used in concealed wiring. If it is good to isolate the junction, then such a wire is not inferior to a solid section.

The technology for such a connection is as follows:

• wires are prepared in the same sequence as before twisting;
• cleaning to a metallic sheen of wire sections;
• solder coating of joints (tinning);
• wires are connected by one of the types of twisting;
• the twisted wires are soldered by solder;
• the place of soldering is processed with an emery cloth. There should be no burrs in the soldering area that could damage the insulation;
• the junction is carefully isolated.

The wires so connected can be placed under the plaster. For reliability, the connection should be placed in a polyvinyl chloride tube.

Welding method

Welding is classified as one-piece joints. This type is the most reliable. It is with this method that the joint section becomes solid. Contact resistance and mechanical strength of the connection section is no different from a solid wire. Welding is carried out both on direct and alternating current.

For professional welding of wires, various types of welding machines are used, but inverter current devices are most widely used. These devices are mobile, they are easily transported on the shoulder of an electrician, differ in small dimensions.

Inverter devices are characterized by a wide range of regulation of the operating current. The welding arc is easily ignited even at low operating currents, and is stable during the entire welding period.

In addition to the welding machine for welding copper wires, it is also necessary to have carbon electrodes coated with copper.

Welding technology consists of several simple operations. To begin with, insulation is removed from the wire. Then, according to the technology described above, wire twisting is performed. Twisted wires are aligned by trimming their ends. In order not to overheat the wires and their insulation, it is necessary to remove heat during the soldering process. For this, a special clamp is used, which is connected to one of the poles of the welding machine. Welding is carried out by touching the ends of the wires of the working electrode, which is held in a welding holder connected to another pole of the welding machine.

Crimping

When crimping, the wires are placed in special mounting sleeves, which are made of the same material as the wires. In this case, from copper. Then the sleeves are compressed with a special tool. When the sleeve is compressed, the wires are deformed. When deformed, the wires are tightly compressed with each other. With local indentation, the wires are deformed in such a way that their individual points penetrate each other's body. Thus, a reliable electrical contact is created, and the junction becomes mechanically strong. Crimping connect the wires that are placed in junction boxes and electrical cabinets.

For crimping, special mounting pliers are used. For connecting wires when installing wiring in residential premises, crimping tongs of the PK-16 model were widely used. For connecting copper wires, connecting copper sleeves of the GM type are used. They are made of copper and have a red color.

In order that the junction does not come in contact with oxygen, it is canned with special technical petroleum jelly. Thus, the junction is isolated from the harmful effects of the environment. The wires will not oxidize, and the connection will last a long time. The junction can also be sealed with a heat shrink tube.

Threaded connection

This type of connection is the connection of single-core and stranded wires belongs to the category of detachable connections. For this, special terminal blocks are used, consisting of both the case and the built-in devices designed for screw clamping of the wire. Be sure to communicate or tin wire for a reliable connection. The most widespread use was in connecting end consumers. (fixtures and chandeliers)

It is used to connect wires with a cross section of not more than 2.5 mm 2. With this type of terminal block, up to 8 wires can be connected simultaneously. They are used to connect wires in electrical cabinets. Mainly used for light wiring. In the outlet group, under heavy loads, use more reliable connection options.

This article has a somewhat provocative title. I am sure that there will immediately be people who will instructively write, saying that twisting is illegal and according to the PUE, twisting of wires is prohibited.

Nobody argues with this. If not for the fact that, in spite of everything that is written in the EMP, the vast majority of wire connections in the territory of the former large Soviet country are still twisted.

I will not argue that very good twisting of wires - This is the most reliable and high-quality way to connect wires, although they constantly try to prove it to me. It seems that someone even made a measurement and compared the voltage drop on the twist and on a whole piece of wire, so it turned out to be less on the twist. Perhaps this is something from the field of mythology among electricians. We will simply proceed from the fact that good twisting can be called one of the stages and a very important element of such methods of connecting wires, such as soldering or welding.

Before discussing further about the correct twisting, let's dwell on what will happen if the wires are connected just like that, without technology, "how it happened." In this case, at the point of contact of the two wires occurs. There are two reasons for this - a decrease in the cross-sectional area of \u200b\u200bthe wire at the contact point (mainly due to microprotrusions during connection) and the presence of an oxide film on the wires.

Oxide film - the result of the interaction of the atoms of the metal of which the core consists of oxygen. This oxide film has a very decent resistivity. The oxide film is absent only in noble metals - gold, platinum, etc. (for that they are also “noble”, which do not react with anyone). In silver, the specific resistance of the oxide film is the same as in the metal itself, so silver is actively used in the contacts of various electrical devices.

When the wire is heated by the current passing through it, the transition contact resistance increases even more, because the generated heat is not completely removed to the environment, but also heats the wire itself, including twisting.

As a result, all this can lead to an avalanche-like process, when the place of twisting is more and more heated. Here is one of the causes of fires due to the so-called "faults in the wiring."

I met one case when an aluminum twist in a neighbor’s country house stood for only one day. The reason for this is not only the presence of low-quality twisting, but also the material of the conductive core of the wire. the site has already been written.

The most interesting thing is that no circuit breakers and fuses in the electrical panel will help in this case, because they respond to an increase in current in the circuit. In our case, the current does not change, it just more and more warms up the contact point of the two wires.

Based on this, we can conclude that a good twist of the wires is necessary first of all in order to ensure that the contact transition resistance always remains stable and does not change over time.

So, what do you need to make a good twist of wires?

First you need to remove the insulation without damaging the wire core. The exposed section of the vein is cleaned of dirt with a clean rag dipped in acetone or white spirit. Then we clean the veins with a metal brush or sandpaper to a metallic luster.

Next, we twist the stripped veins with two pliers. To do this, we bend the ends of the wires at an angle of 90 ° at a distance equal to 7-10 diameters of the core from the insulation slice, and start them one after the other. We wind with pliers 5-7 turns of one core to another.

We wind 5-7 turns of another core and seal the connection with pliers, i.e. we tighten with two pliers the turns of the veins in opposite directions. Then tightly bend the ends of the wires.

In order to make a branch, it is necessary to wind 10-15 turns of a branch core around the main core. Seal the branch with two pliers, tightening the turns of the core by moving them in opposite directions. Then bend the end of the branch core tightly. After all these operations, the twist will be mechanically strong and reliable.

There are many other ways to connect twisted wires. All of these methods are even given characteristic names.

For example, here are some ways that are shown in one famous book for young electricians:

The option that I described in this article, using two pliers, has been tested by practice and has never failed.

After creating a high-quality twist, the wires can be soldered (little used due to the complexity), welded (in one of the articles on the site it was somehow proved that).

Good twisting is needed, for example, for a more modern and less time-consuming way of connecting wires - when used, which is a good alternative to electrical tape.

In appearance, it looks like a regular cambric, which is worn on a twist with a margin in both directions. Then the heat shrink tube heats up (for this you can use a regular lighter, but it is better to use an electric hair dryer), tightly wraps around the cable and reliably insulates it.

Do the twisting right!

If you have your favorite options for connecting wires - share and tell about it in the comments to the article!