Which wire connection is best. Types of connection of electrical wires in a junction box

In private construction, sooner or later there is a need for the installation of electrical networks. Some people turn to specialists for help, others want to do it on their own. The process itself is not very difficult if there are certain skills and knowledge of safety standards, but this mainly concerns the connection of wires of the same section.

But quite often situations arise when it is necessary to reliably connect three or more wires to each other, and all of them have a different cross section. In this regard, the question of how to correctly and safely connect wires of various sections is currently one of the most relevant in the installation of electrical networks.

Methods for connecting wires of various sections

Compound copper wires different thickness - this is not the most difficult process. However, for maximum reliability and safety, certain requirements must be observed here. There are several ways to connect three wires of different cross sections:

• welding or soldering;
• using screw terminals;
• using self-clamping terminals;
• bolted connection;
• branch clamp;
• using copper tips.

Three wires of different cross-sections can be securely connected in any of the above ways, but it is important to remember that when installing sockets and switches, you cannot connect cables of different thicknesses to one contact. In this case, the thinnest of them will not be pressed tightly enough. And this, in turn, can adversely affect the safety of operation.

Connecting wires of different sections by welding or soldering

Easiest but enough reliable way connecting cables that have different thicknesses. IN this case three wires can be connected to each other by hard twisting with subsequent fixation. But here it should be remembered that a reliable connection is possible only between wires of approximately the same cross section. The twisting of wires whose diameters differ significantly cannot be reliable.

Twist three wires of different cross-sections with each other carefully. Each copper core should tightly wrap around the next one. The gaps between them should be minimal. Otherwise, it will affect the safety of subsequent operation.

Before proceeding directly to the twisting of the three wires, lay them out in front of you and sort by thickness. You can not wind a thin wire on a thick one - this will affect the quality of the contact. Such a connection will not last long.

Connection of three wires of different cross-sections using screw terminals

Three wires of different thicknesses can be securely connected to each other using special ZVI screw clamps. The clamps are very convenient design and allow you to create contact between cables that have different sections. The strength of the connection is achieved by using separate screws for each clamp.

It is necessary to choose ZVI clamps taking into account the cross section of the wires that will be connected, as well as their current load. For reliable contact, it is recommended to connect three wires of adjacent sections. We conditionally designate the cross section of the connected conductors as SPP, and the permissible continuous current as DDT. Below are the parameters of clamps and wires:

• ZVI-3 - SPP 1 - 2.5; DDT - 3;
• ZVI-5 - SPP 1.5 - 4; DDT - 5;
• ZVI-10 - SPP 2.5 - 6; DDT - 10;
• ZVI-15 - SPP 4 - 10; DDT - 15;
• ZVI-20 - SPP 4 - 10; DDT - 20;
• ZVI-30 - SPP 6 - 16; DDT - 30;
• ZVI-60 - SPP 6 - 16; DDT - 60;
• ZVI-80 - SPP 10 - 25; DDT - 80;
• ZVI-100 - SPP 10 - 25; DDT - 100;
• ZVI-150 - SPP 16 - 35; DDT - 150.

With the right choice of screw terminal, you can create a really reliable connection that will ensure the uninterrupted operation of the electrical network.

Connect wires of different sections with bolts

Another way to connect wires of different sections to each other is to create a contact using bolts, washers and nuts. According to professional electricians, such a connection is the most durable and strong. The process itself is not too complicated, it takes a minimum of time. The procedure goes as follows:

• the copper conductors of the wire are carefully stripped (the length of the stripped section of the conductor depends on the diameter of the bolt);
• the stripped core is bent in the form of a loop;
• the loop is put on the bolt;
• an intermediate washer is installed on top;
• then a loop of wire of a different section is put on and fixed with an intermediate washer.

This continues until all the wires are connected to each other. After putting on the last loop and the last washer, the structure is firmly tightened with a nut.

Use of copper lugs to contact connections

Also very in a simple way creating a reliable connection is the use of copper tips. They are recommended to be used for contacting wires of large diameter. Before proceeding with the procedure, it is necessary to prepare not only the tips themselves, but also special equipment - crimping pliers or a hydraulic press.

With all the obvious advantages, this type of connection has one (but significant) drawback - rather solid dimensions, due to which the resulting structure may not fit in every junction box. Nevertheless, experts actively use this method.

The process of creating a contact is as follows:

• wires of different sections are carefully straightened;
• the veins of each of them are cleaned by about two to three centimeters;
• a tip is put on each stripped core and clamped with a hydraulic press or crimping pliers;
• bolts are then put on, and the wires are connected with a nut.

After all the work has been done, it is necessary to carefully isolate the junction so that no dangerous situations arise during operation.

Self-wiring and creating contacts using terminals

Universal clamp terminals appeared on the market relatively recently, but almost immediately they began to be in serious demand not only among specialists, but also among potential customers who prefer all electro installation work do it yourself at home.

With self-clamping terminals, you can create strong and reliable contacts between several wires ( three or more). The main advantage of such terminal blocks is their almost limitless functionality - they can be used to connect wires whose sizes vary significantly.

The design of the terminals provides for the presence of holes into which pre-stripped conductors are inserted. For example, a wire with a cross section of 1.5 mm can be inserted into one hole, a wire with a diameter of 4 mm into another, a wire with a diameter of 4 mm into the third, and so on. And after their connection, the contact will be quite strong and reliable.

There are several more ways how to connect three or more wires of different diameters, but they are used quite rarely due to the complexity and length of the process itself. If you want to use one of them - consult first with a specialist who is competent in this particular area.

Electricity is not the area where you need to save. It is advisable to do everything carefully, to select high-quality materials, to choose sizes / diameters / ratings carefully. Let's start with the fact that even the conductors must be connected correctly. And choosing how to connect wires is not as easy as it seems.

There are about a dozen ways to connect wires. In general, they can be divided into two groups: those that require special equipment or specific skills and those that can be successfully used by anyone. House master They don't require any special skills.

The first group includes:

• Soldering. When connecting wires of small diameter in the amount of -2-3 pieces - a very reliable method. True, it requires a soldering iron and some skills in owning it.
• Welding. We need a welding machine and special electrodes. But the contact is reliable - the conductors are fused into a monolith.
• Crimping sleeves. Sleeves and special pliers are needed. Sleeves are selected according to certain rules that you need to know. The connection is reliable, but in order to remake it, it will have to be cut off.

All these methods of connecting wires are performed mainly by specialists. If you have the skills to handle a soldering iron or a welding machine, after practicing on unnecessary scraps, you can make them yourself.

Some wiring methods are more popular, others less so.

Ways to connect wires that do not require any specific skills are becoming more and more popular. Their advantage is quick installation, reliable connection. The disadvantage is that “connectors” are needed - terminal blocks, clamps, bolts. Some of them cost quite decent money (Wago terminal blocks, for example), although there are inexpensive options - screw terminal blocks.

So here are the ways to connect wires, which are easy to perform:

Among professionals there are two opposite opinions. Some believe that new ways of connecting wires - clamps - the best way out, as they speed up installation without compromising the quality of the connection. Others say that the springs will someday weaken and the contact will deteriorate. In this matter, the choice is yours.

Technical nuances of different types of wire connections

All types of wire connections described above are used when laying electrical wiring, but a specific type is selected based on several characteristics:

Consider each connection method, the technology for its implementation and the appropriateness of use in various situations.

Soldering electrical wires

One of the oldest and most widespread types of connection. To work, you will need rosin, solder and a soldering iron. The soldering process is as follows:

Actually, this is the end of the soldering of electrical wires. Not the most difficult process but requires certain skills. The main thing is to warm up the junction enough for the solder to flow between all the wires. In this case, you can not overheat, otherwise the insulation will melt. This is the art - not to burn the insulation, but to ensure reliable contact.

When can soldering be used? This method of connecting wires is excellent in low-current electrics. When connecting wires in a junction box, it is no longer very convenient. Especially if there are a lot of wires and / or they are of large diameter. Soldering such a twist is not a task for beginners. In addition, when trying to lay the connection in the junction box, the soldering begins to break down. To the point that some of the wires fall off. In general, the method is good for connecting conductors of small diameters.

Welding conductors in electrical connections

One of the most reliable ways to connect wires is welding. During this process, the metal of individual conductors is brought to the melting point, mixed, after cooling it is a monolith. This method works very well on large diameters or with a large number of connected conductors. It differs not only in excellent contact, which does not weaken over time and does not change its characteristics. It is also mechanically very strong - the fused part does not allow the connection to fall apart even under heavy loads.

The drop at the end of the twist is molten aluminum

Disadvantages are also present. The first one is just that the conductors are fused, that is, the connection turns out to be absolutely one-piece. If you need to remake it, you have to remove the fused part and start all over again. To be able to do this, you always need to leave a small backlog along the length of the wires. The second drawback is that you need a welding machine, skills in handling it, special electrodes for welding aluminum or copper. The main task in this case is not to burn the insulation, but to melt the conductors. To make this possible, they are stripped of insulation by about 10 cm, twisted tightly into a bundle, and then welded at the very end.

Another disadvantage of welding wires is a laborious process, which also requires jewelry precision in handling the welding machine. For the combination of these qualities, many professional electricians do not like this method. If you pull the wiring "for yourself" and know how to handle the equipment, you can spend some time. Just pre-practice on scraps, select the current strength and welding time. Only after several times you get everything perfect, you can start welding wires "in real life".

Crimping

Another method that requires special equipment is crimping wires with sleeves. Sleeves are copper and aluminum, different diameters. The material is selected depending on the material of the conductor, and the size is selected according to the diameter and number of wires in a particular connection. They should fill almost all the space inside the sleeve, but there should be free space. The quality of the contact depends on the correct choice of the sleeve size. This is the main difficulty of this method of connecting wires: the sleeve should not be too large or too small.

The technology of work is as follows:

• The conductors are stripped of insulation (the length of the stripped section is slightly more than the length of the sleeve).
• Each conductor is stripped to bare metal (we remove oxides sandpaper with small grain).
• The wires are twisted, inserted into the sleeve.
• Crimped with special pliers.

It seems that it is not difficult, but it is in the selection of the sleeve and the presence of ticks that the whole difficulty lies. You can, of course, try to compress with pliers or pliers. But it is impossible to guarantee normal contact in this case.

Twisting

In the first section of the article, we deliberately omitted the twisting of wires. According to the current standard, it cannot be used, since it does not provide proper contact and connection reliability. This method can replace any other methods of connecting wires.

Yes, they did wiring on the twists 20-30 years ago and everything worked fine. But what were the loads on the networks then, and what are they now ... Today, the number of equipment in ordinary apartment or a private house has increased significantly and most of the equipment is demanding on power supply. Some types simply will not work at reduced voltage.

Why is twisting so bad? Twisted wires do not make good enough contact. At first, everything is fine, but over time, the metal is covered with an oxide film, which significantly impairs contact. With insufficient contact, the junction begins to heat up, an increase in temperature causes a more active formation of an oxide film, which further worsens the contact. At some point, the twist heats up very much, which can lead to a fire. It is for this reason that it is better to choose any other method. There are some that are even faster and easier to do, but which are more reliable.

Connection isolation

All the methods of connecting wires described above - welding, soldering, crimping with a sleeve - provide for their insulation, since bare conductive conductors must be protected. For these purposes, electrical tape or heat shrink tubing is used.

Everyone probably knows how to use electrical tape, but we’ll tell you a little about heat shrink tubing. This is a hollow polymer tube, which significantly reduces its diameter when the temperature rises (by 2-6 times, depending on the type). The size is selected so that the pre-shrink volume is greater than the diameter of the insulated wires, and the post-shrink volume is less. In this case, a tight fit of the polymer is ensured, which guarantees a good degree of insulation.

Heat shrink tubing for insulation of conductors can be of different diameters and colors

In addition to size, heat shrink tubing is selected according to special characteristics. They are:

• heat-resistant;
• light-stabilized (for outdoor use);
• oil-petrol resistant;
• resistant to chemicals.

The cost of heat shrink tubing is not very high - from $ 0.5 to $ 0.75 per 1 meter. Their length should be slightly longer than the length of the bare conductors - so that one end of the tube is pulled over the insulation of the conductors by about 0.5 cm, and the second sticks out by 0.5-1 cm. After the tube is stretched, take a heat source (you can use a lighter) and heat the tube. Heating temperature can be different - from 60°C to +120°C. After the connection is covered, the heating stops, after which the polymer cools quickly.

It takes a little time to insulate the wires with a heat shrink tube - seconds count - and the quality of the insulation is high. Sometimes, for greater reliability, two tubes can be used - a slightly smaller and a slightly larger diameter. In this case, first put on and warm up one tube, then the second. Such connections can be operated even in water.

Terminal blocks

This method is also preferred by electricians, but it can be easily used by a person who can hold an ordinary screwdriver in his hands. This is one of the first ways to connect electrical wires without soldering. Today, on almost every electrical appliance, you can see a variant of this connection - this is the output block to which the power cord is connected.

Terminal blocks are a contact plate, which is soldered in a plastic (polymer) or carbolite housing. They cost very little, they are available in almost any store selling electrical goods.

Terminal blocks are convenient, inexpensive, allow you to connect copper and aluminum wires, conductors of different diameters, solid and stranded

The connection takes place literally in seconds. The insulation is removed from the conductor (by about 0.5-0.7 cm), the oxide film is removed. Two conductors are inserted into the socket - one opposite the other - and fixed with bolts. These bolts press the metal against the contact plate, making the connection.

The advantage of this connection method: it is possible to connect wires of various sections, single-core with multi-core. The disadvantage is that only a couple of wires are connected. Jumpers must be installed to connect three or more.

PPE caps

Another way to connect wires that does not require special skills is to install PPE caps. They are a plastic cone-shaped case, inside of which a spring is sealed. They come in different sizes - from 0 to 5. You can connect wires of different diameters - each package contains the minimum and maximum and minimum total cross-section of the connected wires. In addition, there are cases simply in the form of a cone, there are with stops "ears" that facilitate their installation. When choosing, pay attention to the quality of the plastic - it should not bend.

Connecting the wires with PPE is very simple: strip the insulation, collect the wires into a bundle, insert it inside the cap and start twisting. A spring inside the cap grips the conductors, helping to twist them. The result is a twist, which is wrapped around the outer side with spring wire. That is, the contact is very high quality and good. This method of connecting wires with PPE caps has been used for a long time in Europe and America, it came to us about 10 years ago.

If you need ways to connect wires without welding - consider PPE

There is another way: first, the wires are twisted, then caps are put on them. This method was invented by the Russian company that produces these wire connectors - KZT. But this technique requires more time, and the quality of the connection is no different.

There is one more point: how long to strip the wire from the insulation. Manufacturers give clear instructions on this matter - each size has its own length of bare conductors. It is designed so that all conductors without insulation are inside the case. If you do this, the connection does not require additional insulation, which greatly speeds up the process. In addition, the expanded lower part does not prevent heat removal and such a connection is heated less.

Practicing electricians advise to strip the wires by 5-10 cm, and insulate the twist left without insulation. This is argued by the fact that the contact area with this option is larger. It is true, but this option heats up more. And the standard solution has reliability. there are no problems with contact (with normal quality of PPE).

Wago clamps

The most heated debate flared up precisely about Vago. Some people absolutely love this product, others don't. And, no less emphatically. Opponents of using Wago do not like the fact that the contact is based on a spring. They talk about how she might weaken. This will lead to poor contact and overheating. And they bring photos with melted clamps. Supporters of this method conduct tests and comparisons, they say that a properly selected branded clip lasts for many years without signs of deterioration in contact. Yes, and manufacturers say that, subject to technology, Wago terminal blocks can be used for 25-35 years. It is important to choose the right type and parameters and not buy a fake (there are a lot of them).

There are two types of Vago clamps. The first series is slightly less expensive, called Wago. These clamps are suitable for connecting solid and stranded wires with a cross section of 0.5-4 mm2. For conductors of smaller or larger cross sections, there is another series - Cage Clamp. It has a very wide range of use - 0.08-35 mm2, but also a high cost. In any case, the contact is provided by a good copper contact plate. The special shape of the plate allows you to achieve reliable contact.

Detachable

In addition, Vago spring-loaded clamps are detachable (222 series) and one-piece (773 and 273 series). Detachable ones are convenient to install in those places where changes in the network configuration are possible. For example, in junction boxes. They have levers with which the wires are clamped or released. Detachable Wago terminal blocks can connect from 2 to 5 conductors. Moreover, they can be of different sections, types (single-core and multi-core). The order of connecting the wires is as follows:

We repeat the same operation with another (other) wires. All this takes a matter of seconds. Very fast and convenient. Not surprisingly, many professional electricians have forgotten other ways to connect wires.

One-piece

One-piece series differ in structure: there is a clamp body and a cap. The cap can be made of transparent polymer (773 series) or opaque plastic (223). There are holes in the case into which wires stripped of insulation are inserted.

To ensure normal contact, it is only necessary to remove the insulation correctly - exactly by 12-13 mm. These are the requirements of the manufacturer. After the conductor is inserted, the bare part of it should be in the terminal block, and the insulation should rest against the housing. Under such conditions, the contact will be reliable.

Bolted connection

Another type of connection of electrical wires with a solid experience is bolted. It is called so because a bolt, nut and several washers are used to connect the wires. Contact through the use of washers is good, but the whole structure takes up a lot of space and is inconvenient to install. It is mainly used if it is necessary to connect conductors from different metals - aluminum and copper.

The connection build order is as follows:

• We clean the wires from insulation.
• From the cleaned part we form a loop, the diameter of which is equal to the diameter of the bolt.
• We put on the bolt in the following sequence
  • washer (it rests on the head of the bolt);
  • one of the conductors;
  • another puck;
  • second conductor;
  • third puck;
• We tighten everything with a nut.

So you can connect not only two, but also three, and more wires. Please note that it is necessary to tighten the nut not only by hand. Must use spanners put in a solid effort.

The best ways to connect wires for different occasions

Since different wires can be connected, they can be operated in different conditions, then the optimal method must be chosen taking into account all these nuances. Here are the most common situations:

These are the most common options for non-standard connections.

In order for the power supply in your homes to always be of high quality, uninterrupted and reliable, it is very important to correctly connect the wires during installation work. There are a lot of ways, we will consider each one in detail with its advantages and disadvantages, with step by step instructions performing switching. We will also pay attention to the eternal question of electricians - how to connect wires whose cores are made of different metals (for example, copper and aluminum).

Removing the insulating layer from the wires

Immediately I would like to dwell on a question that will be common to any method. Before connecting the wires into a common electrical unit, they must be stripped from the upper insulating layer.

This can be done with a utility knife. This method is simple, but there is a high probability of damage to the conductive core. To do everything right, you must clearly follow the step-by-step instructions:

1. Place the wire on some flat surface (like a table).
2. Press it with the index finger of your left hand.
3. Right hand take a knife and lightly press it into the insulating sheath of the wire. In order not to hook the metal core, position it towards the cut at an angle. If the angle is right, there is a possibility of a circular notch in the core, as a result of which it may subsequently break.
4. Holding the knife in this position. With the index finger of your left hand, slowly rotate the conductor one full turn, thus notching the insulation around the entire circle.
5. It remains only to pull off the cut piece of insulation.

Professional electricians now already have in their arsenal such a device as a stripper. This is a multifunctional tool, with it you can strip the insulation from the wire or cut the cable. It can be simple, semi-automatic and automatic. Most importantly, when stripping the insulation with a stripper, the conductive core is not damaged. For each standard core diameter, such a tool has a calibrated hole with a cutting edge.

The length to which it is necessary to strip the wire cores is different for each connection method.

Twisting

Let's start with the simplest and most well-known method - twisting. It can also be called the oldest, not for nothing that electricians among themselves call twisting the “grandfather method”.

We will not tell you that such a wire connection is durable and reliable. According to the main document in electrical engineering, PUE (“Rules for Electrical Installations”), twisting is generally prohibited, despite the fact that half a century ago it was used everywhere. The fact is that in those days, the load in the apartments consisted only of lighting, radio or TV. Considering the current load in modern apartments with a huge amount of household appliances used daily, then no old insulation, core cross-sections and wire connection methods are no longer suitable.

Nevertheless, we will talk about twisting, and even in the first place, because it is the main stage in such connection options as welding and soldering.

Positive sides

The most important advantage of twisting is that it requires absolutely no material costs. All you need is a knife to remove the insulating layer from the wire strands and pliers to make the connection.

The second indisputable advantage of twisting is ease of execution. No special knowledge or skills are needed, anyone who has ever held pliers in their hands can do it.

In a twist, several wires can be connected at the same time, but their total number should not exceed six.

Negative sides

The main disadvantage of twisting is its unreliability, it weakens over time. This is due to the fact that there is a residual elastic deformation in the cores of the cable or wire. In the place of twisting, the transition resistance increases, which is fraught with a breakdown in contact and heating. In the best case, you will find it in time and re-seal the junction, in the worst case, a fire may occur.

Using twisting, it is impossible to connect electrical wires made of different metals. As an exception, you can twist copper and aluminum wire, but only if the copper core is pre-tinned with solder.

In electrical engineering, there are concepts of a detachable or one-piece connection. So twisting does not apply to either one or the other. A detachable connection is characterized by the fact that its ends can be separated many times. In twisting, this cannot be fully done, each time after the next promotion and twisting of the cores, they will deteriorate. It is also impossible to call twisting an integral connection, because it does not have the concepts of strength, reliability and stability necessary for this. This is another disadvantage of the twisted connection.

Mounting

If for some reason you do not have the opportunity to use other methods of connecting electrical wires, you can use twisting, just do it with high quality. Very often it is used as a temporary option and is subsequently replaced by more reliable switching methods.

How to connect wires with a twist? To begin with, the veins are cleaned by 70-80 mm. The main thing is to twist all switched conductors into one single twist at the same time, and not wind one around the other.

Many mistakenly begin to twist the cores together from the place where the insulating layer ends. But it is better in this place to clamp both cores with one pair of pliers, and with the second to grab the ends of the wires and produce rotational movements in a clockwise direction.

If the wire section is small, you can twist it by hand. Align the conductors with the insulation shear and hold them firmly in this place with your left hand. Bend all switched tips into one single bend at an angle of 90 degrees (a bend length of 10-15 mm will be enough). Hold this fold with your right hand and rotate it clockwise. This must be done firmly and firmly. If it is already difficult to twist with your hands at the end, use the pliers, as described above. As soon as the twist becomes even and beautiful, you can cut the bend.

You can also connect several wires in this way, but then, to make it easier to twist them, make the bend longer, somewhere around 20-30 mm.

How to properly twist the wires is shown in this video:

There is also a way to twist wires with a screwdriver, see about it here:

For twisting wires with a special tool, see here:

Now the resulting twist must be carefully insulated. For this, electrical tape is used. Do not spare it, wind it in several layers, and isolate not only the connection itself, but also step 2-3 cm over the insulation of the cores. Thus, you will ensure the insulating reliability of the twist and protect the contact connection from moisture.

You can also insulate the connection of wires with the help of thermotubes. The main thing is not to forget to put the tube on one of the wires to be connected in advance, and then put it on the place of the twist. Under heat, the thermal pipe shrinks, so slightly heat its edges, and it will firmly wrap around the wire, thereby providing reliable insulation.

If the twisting is done with high quality, it is likely that it will serve you for many years, provided that the load current in the network is normal. But still, it is better not to stop at this stage and strengthen the junction by welding or soldering.

Soldering

Soldering is when electrical wires are connected using molten solder. This type of connection is most suitable for copper wires. Although there are now various fluxes for aluminum, experienced electricians prefer to refrain from such soldering. But if necessary, you can use special fluxes and even solder copper with aluminum.

Positive sides

This type of connection with twisting can no longer be compared, soldering is much more reliable (in terms of reliability, it is second only to welding).

With the help of soldering, it is possible to connect stranded and solid wires, as well as conductors of various sections.

This type of connection does not require any maintenance during the entire period of operation.

Soldering is considered low in cost, only a soldering iron is needed from the fixtures, and flux and solder are quite inexpensive, and their consumption is quite meager.

Negative sides

The disadvantages of this method include high labor intensity. Soldering requires certain preparatory work, the cores of the wires must first be tinned before twisting. The surfaces to be soldered must be free from oxides and absolutely clean before starting work.

And of course, you need experience in owning a soldering iron, that is, the one who will connect the wires by soldering must have a certain qualification. After all, in the process of soldering it is very important to withstand the necessary temperature regime. An underheated soldering iron will not warm up the connection well; overheating is also unacceptable, because the flux will burn out very quickly, not having time to do its job.

Soldering is not a fast process, but this minus is compensated by the reliability that is obtained from the contact connection.

Mounting

The soldering process is as follows:

1. Remove the insulation from the cores by 40-50 mm.
2. Clean the exposed areas of the veins to a shine with sandpaper.
3. Dip a heated soldering iron into the rosin and run it over the cleaned surfaces several times.
4. Perform a twist.
5. Bring the tip of the soldering iron to the solder.
6. Now immediately heat the twist with solder, the tin should melt and fill the gaps between the turns.
7. Thus, the entire twist is enveloped in tin, after which it is allowed to cool.
8. Wipe hardened solder with alcohol and insulate.

Soldering wires with a soldering iron is shown in this video:

Soldering wires with a gas soldering iron:

Soldering twists by immersion in molten solder:

Welding

In order for the connection of electrical wires to be as reliable as possible, the considered method of twisting must be further fixed by welding. It is similar to soldering, only now a welding machine is used instead of a soldering iron.

Positive sides

This method is most preferable over all the others, as it meets all regulatory requirements in terms of reliability and quality.

The welding method is based on the contact heating of the ends of the wires with a carbon electrode until a ball (contact point) is formed. This ball is obtained as a single whole from the fused ends of all connected wires, which ensures safe and reliable contact, it will not weaken and oxidize over time.

Negative sides

The disadvantage of welding is that certain knowledge, experience, skills and special devices are needed to carry out such work, and you often have to turn to specialists.

Mounting

In order to connect wires by welding, you will need the following fixtures, tools and materials:

• welding inverter with a power of at least 1 kW, its output voltage must be up to 24 V;
• carbon or graphite electrode;
• glasses or a mask to protect the eyes;
• welding leather gloves for hand protection;
• fitter's knife or stripper for removing the insulating layer from the conductors;
• sandpaper (for cleaning the connected conductive surfaces);
• insulating tape for further insulation of the welding joint.

The sequence of work is as follows:

1. Free each connected wire from insulation by 60-70 mm.
2. Clean bare veins to a shine with sandpaper.
3. Twist, after biting off, the length of its tips should be at least 50 mm.
4. Fasten the ground clamps on top of the twist.
5. To ignite the arc, bring the electrode to the bottom of the twist and lightly touch the connected wires with it. Welding is very fast.
6. It turns out a contact ball, which is given time to cool, then insulate with tape.

As a result, an almost solid wire is obtained at the end, that is, the contact will have the lowest transition resistance.

If you connect copper wires in this way, then choose a carbon-copper electrode.

I would like to recommend that if you purchase a welding machine (after all, it is useful not only for connecting wires, but also for many other purposes), then choose the inverter option. With small dimensions, weight and power consumption, it has a wide range of welding current adjustment and produces a stable welding arc. And this is very important to be able to regulate the welding current. If it is chosen correctly, the electrode will not stick, and the arc will hold steadily.

How welding is performed, see this video:

We examined the main types of wire connections. Now let's briefly talk about methods that are used less often, but also guarantee quality and reliability.

Crimping

For this method, special tubular sleeves or lugs are used, with which the wires to be connected are crimped and crimped. The essence of the method lies in the joint deformation of the sleeve and the cores inserted into it. During deformation, the sleeve is compressed and squeezes the conductive surfaces. The conductors are interlocked, which ensures the reliability of electrical contact.

The advantage of such a connection is reliability, as well as the fact that it can be classified as “done and forgot”, it does not need maintenance.

But along with the positive aspects, the pressure test also has a number of disadvantages. First, a special tool is required (crimper or mechanical or hydraulic pliers). Secondly, the quality of the connection directly depends on the correctly selected sleeve (it is selected depending on the number of connected cores and their cross section).

Before connecting two wires using crimping, they are not only stripped of insulation, but also lubricated with a special paste. Aluminum is treated with quartz-vaseline paste, it removes the oxide film and prevents it from reappearing. For copper conductors, quartz impurities are not needed, technical petroleum jelly is enough. It is needed to reduce friction. Also, lubrication minimizes the risk of damage to the cores during deformation.

Next, the cores must be inserted into the sleeve until they are mutually stop, and alternate crimping is performed on both sides. The pressed joint is insulated with an insulating tape, varnished cloth or a thermotube.

How to connect wires with sleeves is shown in these videos:

Bolted connection

Bolts for connecting wires used to be often used, now this method is more common in high voltage circuits. The contact is reliable, but the electrical assembly connected in this way turns out to be too cumbersome. Until recently, large junction boxes were installed in apartments, in them at least somehow, but it was possible to arrange such a connection. Modern boxes are smaller and are not designed for switching wires in this way.

But you definitely need to know about it, because this is one of the ways to solve the eternal problem of connecting conductors made of various metals. The bolt contact is ideal for switching absolutely incompatible conductors - thin and thick, aluminum and copper, solid and stranded.

The cores of the wires must be stripped and the ends twisted in the form of rings. A steel washer is put on the bolt, then the rings of the wires to be connected are thrown on (this is the case when they are made of homogeneous metal), then another steel washer follows and everything is tightened with a nut. If aluminum and copper wires are connected, one more additional washer must be placed between them.

The advantage of this connection is its simplicity. If necessary, the bolted structure can always be untwisted. If necessary, you can add more strands of wires (as far as the length of the bolt allows).

The most important thing in this type of connection is to prevent direct contact between copper and aluminum, do not forget to lay an additional washer between them. And then such a switching unit will last a long time and reliably.

Modern technologies

In many cases, the methods discussed are gradually becoming a thing of the past. They were replaced by factory wire connectors, which greatly facilitated and accelerated installation and switching work:

1. Terminal blocks with tubular brass sleeves inside. Stripped wire strands are inserted into these tubes and fixed by tightening the screws.
2. PPE caps with compression springs inside. The cores are inserted into the cap and then it is turned clockwise with a little effort, thereby the connected wires are reliably squeezed inside.
3. Self-clamping terminals. It is enough to place the wiring in them, and there it is automatically fixed due to the pressure plate.
4. Lever-type terminal blocks. Such a connecting element is reusable. It is enough just to raise the lever, insert the conductor into the contact hole and lower the lever back, reliable fixation is provided.

We do not talk in detail about all the existing terminal blocks, since there is a separate article about this, which discusses in detail each type of wire clamp.

We hope that we have clearly explained to you how to connect the wires correctly. Choose the method that suits you best. When choosing, take into account the cross section and material of the conductors, the location of the connection (outdoors or indoors), the amount of load current that will flow in this electrical circuit.

At serial connection wires of different diameters, the maximum load current will be determined by the cross section of the wire with a smaller diameter. For example, copper wires with a diameter of 1.6 mm and 2 mm are connected. In this case, the maximum load current on the wiring, which is determined from the table, will be 10 A, and not 16 A, as for a wire with a diameter of 2 mm.

Twisting electrical wires

Until recently, twisting was the most common way to connect wires when making electrical wiring, due to availability, it was enough to have a knife and pliers from the tool. But, according to statistics, twisting is not a reliable way to connect conductors.

According to the rules for the installation of electrical installations (PUE), the connection of the type of twist during the installation of electrical wiring is prohibited. But, despite the noted shortcomings, the twisting method is currently widely used. The twisted connection of conductors of low-precision circuits, subject to certain rules, is fully justified.

The photo on the left shows how it is unacceptable to twist. If one conductor is wrapped around another, then the mechanical strength of such a connection will be insufficient. When twisting wires, it is necessary to make at least three turns of wires around each other. In the middle photo, the twisting is done correctly, but the copper conductor is twisted with aluminum, which is not acceptable, since when copper contacts aluminum, an EMF of more than 0.6 mV occurs.

In the photo on the right, the twisting of copper and aluminum wires is done correctly, since the copper wire is tinned with solder before twisting. You can twist together several wires at once, in a junction box, it happens that up to 6 conductors are twisted, wires of different diameters and from different metals, a stranded wire with a single-core wire. Only the stranded wire must be made single-core, after being soldered with solder.

Connecting electrical wires by soldering

The connection of copper wires with high-quality soldering is the most reliable and is practically not inferior to a solid wire. All of the above examples of wire twists, except for aluminum and tinsel, when the conductors are tinned before twisting and then soldered with solder, will be reliable on a par with solid wires. The only downside is the extra work involved, but it's worth it.

If you need to connect a pair of wires and the conductors from twisting should be directed in different sides, then a slightly different type of twist is used.

By splicing two pairs of double wires in the manner described below, it is possible to obtain a compact and more beautiful connection by twisting both single-core and stranded pairs of conductors. This twisting method can be successfully applied, for example, when splicing broken wires in a wall, extending a wire when moving a socket or switch from one place on the wall to another, when repairing or extending the length of the carrying cable.

To obtain a reliable and beautiful connection, it is necessary to adjust the lengths of the ends of the conductors with a shift of 2-3 cm.

Perform pairwise twisting of the conductors. With this type of twisting, two turns are enough for a single-core wire, and five for a stranded wire.

If you plan to hide the twist under plaster or in another inaccessible place, then the twist must be soldered. After soldering, you need to go over the solder with sandpaper to remove any sharp solder icicles that can pierce the insulation and stick out of it. You can do without soldering if the connection is accessible and there are not large currents flowing through the conductors, but the durability of the connection without soldering will be much lower.

Due to the shift of the twist points, it is not necessary to isolate each of the connections separately. We attach on both sides along the conductors along a strip of insulating tape. In conclusion, you need to wind three more layers of insulating tape. According to the requirements of the Electrical Safety Rules, there must be at least three layers.

The wires, strated and soldered in the manner described above, can be safely laid in the wall and plastered on top. Before laying, it is desirable to protect the connection with a vinyl chloride tube, dressed in advance on one of the pairs of wires. I have done this several times, and the reliability has been confirmed by time.

Connecting wires in junction boxes

When I moved into an apartment built in 1958 and began to make repairs, I immediately encountered the flashing of lighting bulbs in time with hammer blows on the walls. There was a primary task of repair, revision of junction boxes. Opening them showed the presence of poor contact in the twists of copper wires. To restore contact, it was necessary to disconnect the twists, clean the ends of the wires with sandpaper and twist again.

When trying to disconnect, I ran into a seemingly insurmountable obstacle. The ends of the wires broke off even without any effort. Over time, copper lost its elasticity and became brittle. When stripping the wire, the insulation was obviously cut with a knife blade in a circle and notches were made. In these places, the wire broke off. Copper hardened from temperature fluctuations.

To return copper elasticity, unlike ferrous metals, you can heat it to red and quickly cool it. But for this case, this approach is not acceptable. The ends of the wires were no more than 4 cm long. There was no choice for the connection. Only solder.

I stripped the wires with a soldering iron, melted the insulation, tinned them with solder, tied them in groups with tinned copper wire and filled them with solder using a 60-watt soldering iron. The question immediately arises, how to solder the wires in the junction box if the wiring is de-energized? The answer is simple, using a battery powered soldering iron.

So updated connections in all junction boxes, spending no more than 1 hour on each. I am fully confident in the reliability of the connections made, and this has been confirmed by the 18 years that have passed since then. Here is a photo of one of my boxes.

When leveling the walls with Rotband in the hallway and installing a stretch ceiling, the junction boxes became a hindrance. I had to open them all, and the reliability of the solder joint was confirmed, they were in perfect condition. So I boldly hid all the boxes in the wall.

The connections currently practiced with the help of a Wago flat spring clamp terminal block greatly reduce the time spent on installation work, but are much inferior in reliability to solder connections. And in the absence of spring-loaded contacts in the block, they completely make connections in high-current circuits unreliable.

Mechanical connection of wires

Soldering is the most reliable type of connection of wires and contacts. But it has disadvantages - not the detachability of the obtained connections and the high labor intensity of the work. Therefore, the most common type of connection of wires with electrical contacts of devices is threaded, screws or nuts. For the reliability of this type of connection, it is necessary to perform them correctly.

The linear expansion from temperature changes is different for metals. Aluminum changes the linear dimensions especially strongly, then in descending order, brass, copper, iron. Therefore, over time, a gap is formed between the contact of the connected metals, which increases the resistance of the contact. As a result, to ensure the reliability of the connections, it is necessary to tighten the screws periodically.

In order to forget about maintenance, additional washers with a cut are installed under the screws, which are called split washers or Grover. The grower selects the resulting gaps and thus ensures a high contact reliability.

Often, electricians are lazy, and the end of the wire is not twisted into a ring. In this embodiment, the area of ​​contact of the wire with the contact pad of the electrical appliance will be many times smaller, which reduces the reliability of the contact.

If the formed wire ring is slightly flattened with a hammer on the anvil, then the contact area will increase several times. This is especially true when forming a ring of stranded wire soldered with solder. Instead of a hammer, flatness can be given with a needle file by grinding off a little ring at the points of contact with the contacts.

This is how it should be done ideal threaded connection of wires with contact pads of electrical appliances.

Sometimes it is required to connect copper and aluminum conductors to each other, or with a diameter of more than 3 mm. In this case, the most accessible is a threaded connection.

The insulation is removed from the wires for a length equal to four screw diameters. If the veins are covered with oxide, then it is removed with sandpaper and rings are formed. A spring washer, a simple washer, a ring of one conductor, a simple washer, a ring of another conductor, a washer and, finally, a nut are put on the screw, screwing the screw into which the entire package is tightened until the spring washer is straightened.

For conductors with a core diameter of up to 2 mm, an M4 screw is sufficient. The connection is ready. If the conductors are of the same metal or when connecting an aluminum wire to a copper wire, the end of which is tinned, then it is not necessary to lay a washer between the rings of the conductors. If the copper wire is stranded, then it must first be soldered.

Connecting wires with a terminal block

The connection of wires with a low current load can be performed using terminal blocks. Structurally, all terminal blocks are arranged in the same way. Thick-walled brass tubes with two threaded holes on the sides of each are inserted into the combs of the body made of plastic or carbolite. Connected wires are inserted into opposite ends of the tube and fixed.

The tubes come in different diameters and they are selected depending on the diameters of the connected conductors. You can insert as many wires into one tube as it will allow. inner diameter.

Although the reliability of connecting wires in terminal blocks is lower than when connecting by soldering, much less time is spent on wiring. The indisputable advantage of terminal blocks is the ability to connect copper and aluminum wires in electrical wiring, as brass tubes are plated with chromium or nickel.

When choosing a terminal block, it is necessary to take into account the current that will pass through the switched wires of the electrical wiring and the required number of terminals in the comb. Long combs can be cut into several short ones.

Connecting wires using a terminal block
with flat spring clip Wago

Terminal blocks with a flat spring clip Wago (Vago) of a German manufacturer are widely used. Wago terminal blocks come in two designs. Disposable, when the wire is inserted without the possibility of removal, and with a lever that allows you to easily insert and remove the wires.

The photo shows a Wago disposable terminal block. It is designed to connect any type of single-core wires, including copper and aluminum wires with a cross section of 1.5 to 2.5 mm 2. According to the manufacturer, the block is designed to connect electrical wiring in junction and distribution boxes with a current of up to 24 A, but I doubt it. I think that it is not worth loading the Wago terminals with a current of more than 10 A.

Wago spring terminal blocks are very convenient for connecting chandeliers, connecting wires in junction boxes. It is enough just to force the wire into the hole in the block, and it will be securely fixed. In order to remove the wire from the block, considerable effort is required. After removing the wires, deformation of the spring contact may occur and a reliable connection of the wires when reconnecting is not guaranteed. This is big disadvantage disposable clamp.

A more convenient Wago reusable terminal block with an orange lever. Such terminal blocks allow you to connect and, if necessary, disconnect any wires of electrical wiring, single-core, stranded, aluminum in any combination with a cross section from 0.08 to 4.0 mm 2. Designed for current up to 34 A.

It is enough to remove the insulation from the wire by 10 mm, lift the orange lever up, insert the wire into the terminal and return the lever to its original position. The wire is securely fixed in the terminal block.

The Wago terminal block is modern means Tool-free wire connections are quick and reliable, but more expensive than traditional connection methods.

Permanent connection of wires

In some cases, when it is not supposed to switch the wires in the future, they can be connected in an integral way. This type of connection is highly reliable, and is advisable in hard-to-reach places, for example, connecting the ends of a nichrome spiral with copper current-carrying conductors in a soldering iron.

Connection of thin wires by crimping

A simple and reliable way to connect wire cores is crimping. Wire strands are inserted into a piece of copper or aluminum, depending on the metal of the wires being connected, and the tube is pressed in the middle with a tool called press tongs.

Crimping can connect both single-core and stranded wires in any combination. The diameter of the tube must be selected depending on the total cross section of the conductors. It is desirable that the conductors fit tightly. Then the reliability of the connection will be high. If in a stranded wire the conductors are interconnected, then it is necessary to develop and straighten them. It is not necessary to twist the wire strands together. The prepared conductors are inserted into the tube and crimped with press tongs. The connection is ready. It remains only to insulate the connection.

Crimping lugs are commercially available already equipped with an insulating cap. Crimping is performed by compressing the tube together with the cap. The connection is immediately isolated. Since the cap is made of polyethylene, it deforms during crimping and is securely held, providing reliable isolation of the connection.

The disadvantage of the connection by crimping should include the need for special press - tongs. Ticks can also be made independently from pliers with side cutters. It is necessary to round the side cutter blades and make a groove in the middle. After such refinement of the pliers, the edges of the side cutters will become blunt and will no longer be able to bite, but only squeeze.

Connection of wires of a larger cross-section by crimping

To connect electrical wires of a larger cross section, for example, in power shields of houses, special lugs are used, which are crimped using universal press tongs, such as PK, PKG, PMK and PKG.

For crimping each size of the tip or sleeve, its own die and punch are required, a set of which is usually included in the set of pliers.

To crimp the tip onto the wire, the insulation is first removed from the wire, the wire is threaded into the hole of the tip and wound between the matrix and the punch. For the long handles of the press tongs are compressed. The tip is deformed, compressing the wire.

In order to choose the right die and punch for the wire, they are usually marked and branded press tongs on the die have an engraving for crimping which section of the wire the die is intended for. The number 95 embossed on the tip means that this matrix is ​​designed for crimping in the tip of the wire with a cross section of 95 mm 2.

Connecting wires with a rivet

It is carried out using screw connection technology, only a rivet is used instead of a screw. The disadvantages include the impossibility of disassembly and the need for a special tool.

The photo shows an example for connecting copper and aluminum conductors. For more information about connecting copper and aluminum conductors, see the site article "Connecting aluminum wires". In order to connect the conductors with a rivet, you first need to put an aluminum conductor on the rivet, then a spring washer, then a copper and a flat washer. Insert the steel rod into the riveter and squeeze its handles until it clicks (this is cutting off the excess steel rod).

When connecting conductors made of the same metal, it is not necessary to lay a split washer (Grover) between them, but put the Grover on the rivet first or penultimate, the last must be an ordinary washer.

Connecting broken wires in the wall

Repairs should begin with a very careful removal of plaster in the area of ​​\u200b\u200bdamaged wires. This work is done with a chisel and a hammer. As a chisel when laying electrical wiring in the wall, I usually use the rod from a broken screwdriver with a sharply sharpened end of the blade.

Connection of copper wires interrupted in the wall

A segment is taken copper wire, with a cross section not less than the cross section of a broken wire. This piece of wire is also covered with a layer of solder. The length of this insert should provide an overlap on the connected ends of the wires by at least 10 mm.

The insert is soldered with the connected ends. Solder should not be saved. Next, the insulating tube is shifted in such a way as to completely close the junction. If a sealed moisture-resistant connection is required, then before putting on the tube, the soldered connection must be coated with silicone.

Connection of aluminum wires interrupted in the wall

A prerequisite for obtaining a reliable mechanical connection of aluminum wires is the use of a washer type Grover. The assembly of the connection is performed as follows. A grover is put on the M4 screw, then an ordinary flat washer, rings of connected wires, then a simple washer and nut.

Step-by-step instructions for connecting broken wires in the wall are described in the article "Connecting broken wires in the wall"

Connecting wires with push-on terminals

Detachable connection of conductors with the help of cap terminals, which are put on contacts with a thickness of 0.8 and a width of 6.5 mm, are widely used in household appliances and cars. The reliability of fixing the terminal is ensured by the presence of a hole in the center of the contact, and a protrusion in the terminal.

Sometimes the conductors break off, and more often the terminal itself burns due to poor contact, and then it becomes necessary to replace it. Typically, the terminals are pressed onto the ends of the conductors using special pliers. Crimping can also be done with pliers, but there is not always a new replacement terminal on hand. You can successfully use a used one by mounting the terminal using the following technology.

First you need to prepare the old terminal for re-assembly. To do this, holding the terminal with pliers at the place of pressing, you need to spread the antennae that compress the insulation with an awl or a screwdriver with a thin sting. Further, the wire is repeatedly bent, until it breaks at the exit point from the pressing. To speed up, you can cut this place with a knife.

When the wire is separated from the terminal, a place is prepared with a needle file for soldering it. It is possible to completely grind off until the remaining wire is released, but this is not necessary. It turns out a flat area.

The resulting site breaks through with solder. The conductor is also cleaned and tinned with solder using a soldering iron.

It remains to attach the conductor to the prepared terminal site and warm up the soldering irons. The antennae that fix the wire are bent after soldering the wire to the terminal, since if they are crimped before soldering, the antennae will melt the insulation.

It remains to pull on the insulating cap, put the terminal on the desired contact and check the reliability of fixation by pulling the wire. If the terminal jumped off, then it is necessary to tighten its contacts. A self-made soldered terminal on a wire is much more reliable than one obtained by crimping. Sometimes the cap is worn so tightly that it cannot be removed. Then it must be cut and, after mounting the terminal, cover it with insulating tape. You can also stretch a piece of vinyl chloride or heat-shrinkable tubing.

By the way, if you hold a PVC tube for five minutes in acetone, then it increases in size by one and a half times and becomes plastic, like rubber. After evaporation of acetone from its pores, the tube returns to its original size. In this way, about 30 years ago, I isolated the base of light bulbs in a Christmas tree garland. So far, the insulation is in excellent condition. I still hang this garland of 120 6.3 V bulbs on the Christmas tree every year.

Splicing stranded wires without twisting

You can splice stranded wires in the same way as single-core ones. But there is a more perfect way, in which the connection is more accurate. First you need to adjust the length of the wires with a shift of a couple of centimeters and strip the ends to a length of 5-8 mm.

Fluff the slightly cleaned areas of the pair to be joined and insert the resulting “panicles” into each other. In order for the conductors to take a neat shape, they must be pulled together with a thin wire before soldering. Then lubricate with soldering varnish and solder with solder.

All conductors are soldered. We clean the places of soldering with sandpaper and isolate. We attach on both sides along the conductors one strip of electrical tape and wind a couple more layers.

This is what the connection looks like after being covered with electrical tape. Can be further improved appearance, if you sharpen the places of soldering with a needle file from the side of the insulation of adjacent conductors.

The strength of the connected stranded wires without soldering is very high, which is clearly demonstrated by the video. As you can see, the weight of the monitor is 15 kg, the connection can withstand without deformation.

Connecting wires with a diameter of less than 1 mm with a twist

We will consider the twisting of thin conductors using the example of twisted pair cable splicing for computer networks. For twisting, thin conductors are released from insulation for a length of thirty diameters with a shift relative to adjacent conductors and then twisted in the same way as thick ones. Conductors must wrap themselves around each other at least 5 times. Then the twists are bent in half with tweezers. This technique increases the mechanical strength and reduces the physical size of the twist.

As you can see, all eight conductors are connected with a sheared twist, which eliminates the need to insulate each of them individually.

It remains to fill the conductors in the cable sheath. Before refueling, to make it more convenient, you can pull the conductors with a coil of insulating tape.

It remains to fix the cable sheath with insulating tape and the twist connection is completed.

Connection of copper wires in any combination by soldering

When connecting and repairing electrical appliances, it is necessary to lengthen and connect wires with different cross-sections in almost any combination. Consider the case of connecting two stranded conductors with different cross sections and number of cores. One wire has 6 conductors with a diameter of 0.1 mm, and the second has 12 conductors with a diameter of 0.3 mm. Such thin wires cannot be reliably connected with a simple twist.

With a shift, you need to remove the insulation from the conductors. The wires are tinned with solder, and then the smaller wire is wound around the larger wire. It is enough to wind a few turns. The place of twisting is soldered with solder. If you want to get a direct connection of wires, then the thinner wire is bent and then the junction is insulated.

Using the same technology, a thin stranded wire is connected to a single-core wire with a larger cross section.

As is obvious from the technology described above, any copper wires of any electrical circuits can be connected. At the same time, one should not forget that the permissible current strength will be determined by the cross section of the thinnest wire.

TV coaxial cable connection

It is possible to extend or splice a coaxial television cable in three ways:
- TV extension cable, on sale are from 2 to 20 meters
– using an adapter TV F socket - F socket;
- soldering with a soldering iron.

Tinsel wire connection
stranded with solid or stranded conductor

If necessary, to give the cord a very high flexibility and at the same time greater durability, the wires are made using a special technology. Its essence lies in the winding of very thin copper ribbons on a cotton thread. Such a wire is called tinsel.

The name is borrowed from tailors. Gold tinsel is used to embroider the parade uniforms of high military ranks, coats of arms and much more. Copper tinsel wires are currently used in the production of high-quality products - headphones, landline telephones, that is, when the cord is subjected to intense bending during use of the product.

As a rule, there are several conductors of tinsel in the cord, and they are twisted together. Soldering such a conductor is almost impossible. To connect the tinsel to the contacts of the products, the ends of the conductors are crimped into the terminals with a special tool. To perform a reliable and mechanically strong connection by twisting without a tool, you can use the following technology.

The conductors of tinsel 10-15 mm and the conductors with which it is required to connect the tinsel to a length of 20-25 mm with a shift with a knife in the manner described in the site article "Preparing wires for installation" are released from insulation. The tinsel thread is not removed.

Then the wires and the cord are applied to each other, the tinsel is bent along the conductor and the core of the wire is tightly wound onto the tinsel pressed against the insulation. It is enough to make three to five turns. Next, the second conductor is twisted. You will get a fairly strong twist with a shift. Several turns are wound with insulating tape and the connection of tinsel with a single-core wire is ready. Thanks to shear technology, the connections do not need to be insulated individually. If you have a heat-shrinkable or PVC tube of a suitable diameter, you can put on a piece of it instead of an insulating tape.

If you want to get a straight connection, then you need to turn the single-core wire by 180 ° before insulating. In this case, the mechanical strength of the twist will be greater. The connection of two cords with tinsel-type conductors to each other is carried out according to the technology described above, only for wrapping a piece of copper wire with a diameter of about 0.3-0.5 mm is taken and at least 8 turns must be made.

When wiring or repairing electrical wiring, when connecting household appliances and a lot of other work, it is required to connect conductors. In order for the connection of wires to be reliable and safe, it is necessary to know the features of each of them, where and when, under what conditions they can be used.

Existing methods of connecting conductors

To connect the wires can be done in several ways:

• welding is the most reliable method, providing high reliability of the connection, but requiring skills and the presence of a welding machine;
• terminal blocks - a simple and fairly reliable connection;
• soldering - works well if the currents do not exceed the normative ones and the connection does not heat up to temperatures above the norm (65 ° C);
• crimping with sleeves - requires knowledge of technology, special pliers, but the connection is reliable;
• the use of spring clips - wago, PPE - quickly installed, subject to operating conditions provide good contact;
• bolted connection - easy to perform, usually used in difficult cases- if necessary, the transition from aluminum to copper and vice versa.

The specific type of connection is selected based on many factors. It is necessary to take into account the material of the conductor, its cross section, the number of cores, the type of insulation, the number of conductors to be connected, as well as the operating conditions. Based on these factors, we will consider each of the types of connections.

Welding – high reliability in all conditions

When connecting wires by welding, the conductors are twisted, and their end is welded. As a result, a ball of metal is formed, which provides a stable and very reliable connection under any conditions. Moreover, it is reliable not only in terms of electrical characteristics, but mechanically too - the metal of the connected wires after melting forms a monolith and it is impossible to isolate a separate conductor.

Welding - it is important to heat the metal, but not to melt the insulation

The disadvantage of this type of wire connection is that the connection is 100% one-piece. If you need to change something, you need to cut off the fused piece and redo it all over again. Therefore, for such connections, a certain margin of wires is left - in case of a possible alteration.

Other disadvantages include a welding machine, appropriate electrodes, flux and work skills. In addition, welding takes a lot of time, it is necessary to protect surrounding objects, and it is also inconvenient to work with a welder at a height. Because electricians given type compounds are practiced in exceptional cases. If you are doing “for yourself” and know how to handle a welding machine well, you can practice on scraps. The trick is not to melt the insulation, but to weld the metal.

After cooling, the welding site is isolated. You can use electrical tape, you can use heat shrink tubing.

Crimping connection of wires

For crimping wires, a special aluminum or copper sleeve is required - it is selected based on the size of the twist (beam diameter), and the material is taken the same as that of the conductors. The wires that are bare and cleaned to a shine are twisted, a tube-sleeve is put on them, which is clamped with special tongs.

Both sleeves and pliers are different, there are several types. Each of them has its own rules of use (the number of wires that can be packed into a sleeve), in which you need to be well versed. It is necessary to pack the wires according to certain rules, measure the size of the resulting bundle, and adjust it to the requirements. All in all, a pretty tedious job. Therefore, this type of wire connection is mainly used by professional electricians, and even more often they switch to spring clips.

Terminal blocks

One of the simplest and most reliable wire connections is through terminal blocks. There are several types, but almost everywhere a screw connection is used. Available with nests different sizes- for different sizes of conductors, with a different number of pairs - from 2 to 20 or more.

The terminal block itself is a plastic case in which a metal socket or plate is soldered. A bare conductor is inserted into this socket or between the plates, clamped with a screw. After the screw is tightened, it is necessary to pull the conductor well - make sure that it is well clamped. Due to the fact that the connection points remain uninsulated, the scope of the terminal blocks is rooms with normal humidity.

The disadvantage of this connection is that due to the plasticity of metals - especially aluminum - the contact weakens over time, which can lead to an increase in the degree of heating and acceleration of oxidation, and this again leads to a decrease in contact. In general, the connection of wires in screw terminal boxes must be tightened periodically.

Advantages - speed, simplicity, low cost, does not require any skills, except perhaps the ability to use a screwdriver. Another important advantage is that you can easily connect wires of different diameters, single-core and stranded, copper and aluminum. There is no direct contact, therefore there are no risks.

Soldering

First, about soldering technology. The connected conductors are cleaned of insulation, cleaned of oxide film to bare metal, twisted, then tinned. To do this, the conductors are heated with a soldering iron, applied to rosin. It should cover the junction completely. Tinned wires are twisted first with fingers, then squeezed using pliers. Soldering flux can be used instead of tinning. They wet the wires well, but after twisting.

Then, in fact, the soldering process begins: the junction is heated with a soldering iron or a narrow-torch burner. When the rosin or flux begins to boil, take some of the solder on the soldering iron tip, bring it into the soldering area, pressing the tip against the conductors. The solder spreads, filling the gaps between the wires, providing good connection. When using a torch, the solder is simply added little by little to the torch.

Further, after the soldering place has cooled down, according to the technology, it is necessary to wash off the flux residues (they accelerate oxidation), dry the joint, cover it with a special protective varnish, and then insulate it with electrical tape and / or heat shrink tubing.

Now about the advantages and disadvantages of this method of connecting wires. In low-current systems, soldering is one of the most reliable ways to connect wires. But, when wiring electrical wiring in a house or apartment, it is criticized mercilessly. The thing is that the solder has a low melting point. With the periodic passage of high currents through the connection (it happens if the circuit breakers are incorrectly selected or faulty), the solder gradually melts and evaporates. Time after time, the contact gets worse, the connection heats up more and more. If this process is not detected, it may well end in a fire.

The second negative point is the low mechanical strength of soldering. The point is again in tin - it is soft. If there are a lot of wires in a soldered joint, and if they are still rigid, when trying to pack them, the conductors often fall out of the solder - the elastic force that pulls them out is too great. Therefore, the connection of conductors by soldering when distributing electricity is not recommended for use: it is inconvenient, long and risky.

Spring terminals for connecting wires

One of the most controversial ways to connect wires is with spring clamps. There are several types, but the most common two are wago terminal blocks and PPE caps. Externally and by the method of installation, they are very different, but both designs are based on a spring that creates a strong contact with the wire.

There is controversy about this spring. Opponents of using wago say that the spring will weaken over time, the contact will become worse, the connection will start to heat up more and more, which, again, leads to an even faster decrease in the degree of elasticity of the spring. After some time, the temperature may rise so much that the case (plastic) will melt, but what can happen next is known.

Spring clips for electrical wiring - popular wire connection

In defense of the use of spring clamps for connecting wires, if they are used in accordance with the manufacturer's recommendations, problems are very, very rare. Although there are many fakes of both wago and PPE, as well as an abundance of pictures of them in a melted form. But, at the same time, many use them, and, under normal operating conditions, they work for years without any complaints.

Clips for wires wago

They appeared on our market a few years ago and made a lot of noise: with their help, the connection is very fast and easy, while it has high reliability. The manufacturer has specific recommendations for the use of this product:

Inside these devices there is a metal plate, which provides the proper degree of contact. The shape and its parameters of the plates were developed and tested specifically. The tests were carried out on a vibration stand for many hours, then heated-cooled. After that they checked electrical parameters connections. All tests were passed as "excellent" and branded products always show themselves as "five".

In general, the Wago product range is very wide, but for wiring or connecting household appliances, lighting fixtures, two types of wire clamps are used: the 222 series (detachable) with the ability to remake or change the connection and the 773 and 273 series - which are called one-piece.

Detachable

Spring clamps for electrical wiring Wago 222 series has a certain number of contact pads - from two to five - and the same number of flags-clamps. Before starting the connection, the flags are raised up, the conductors stripped of insulation are inserted into them (up to the stop), after which the flag is lowered. At this point, the connection is considered complete.

wago wire connectors - connection methods

If necessary, you can remake the connection - raise the locking flag and remove the conductor. Convenient, fast and reliable.

The 222 vago series can be used to connect two or three, even five conductors made of copper or aluminum (you can connect different metals in one terminal). Wires can be solid or stranded, but with rigid wires. The maximum section is 2.5 mm 2. Soft stranded wires can be connected with a cross section from 0.08 mm 2 to 4 mm 2.

One-piece

There is another type of clamps that does not provide for the possibility of redoing the connection of wires - the 773 and 273 series. When using these terminals, the work is generally seconds: the stripped wire is inserted into the appropriate socket. The spring present there clamps it, providing contact with the plate. Everything.

These spring-loaded wire clamps can be used to connect solid aluminum or copper wires with a cross-sectional area from 0.75 mm2 to 2.5 mm2, stranded wires with rigid wires from 1.5 mm2 to 2.5 mm2. Soft stranded conductors cannot be connected using such connectors.

To improve contact, before connecting the wires, it is necessary to clean the oxide film. To prevent further oxidation, wago manufacturers also produce contact paste. It fills the inside of the clamp and it itself corrodes the oxide film, and then protects the wires from further oxidation. In this case, only highly oxidized, dark conductors need to be pre-stripped, and the clamp body is filled with paste.

By the way, manufacturers say that, if desired, the wire can be pulled out of the clamp. To do this, they take the wire with one hand, hold the terminal box with the other and rotate them back and forth with a small range, in opposite directions, stretching in different directions.

Clips for lamps (construction and installation terminals for lamps)

For quick and convenient connection of lamps or sconces, wago has special terminals of the 224 series. With their help, you can connect aluminum or copper wires of different sections and types (solid or stranded with rigid wires). Rated voltage of this connection is 400 V, rated current:

• for copper conductors - 24 A
• 16 A for aluminum.

Cross-section of connected conductors on the mounting side:

• copper 1.0 ÷ 2.5 mm2 - single-core;
• aluminum 2.5 mm2 - single-core.

Cross-section of connected conductors from the chandelier/sconce side: copper 0.5 ÷ 2.5 mm2 - single-core, stranded, tin-plated, crimped.

When connecting copper wires, the use of contact paste is mandatory, and aluminum wires must be manually stripped to bare metal.

This product has two drawbacks. First, the price of original terminals is high. The second - there are a lot of fakes at a lower price, but their quality is much lower and it is they who burn and melt. Therefore, despite the high cost, it is better to buy original products.

PPE caps

PPE caps (stands for "connecting insulating clips") are very easy to use devices. This is a plastic case, inside of which there is a spring that has a conical shape. Conductors stripped of insulation are inserted into the cap, the cap is scrolled clockwise several times. You will feel that it has stopped scrolling, which means the connection is ready.

How to make a wire connection using PPE

These conductor connectors are produced by many manufacturers, there are different sizes, for different diameters and the number of connected conductors. In order for the wire connection to be reliable, the size must be selected correctly, and for this it is necessary to understand the markings.

After the letters of the PPE comes a few numbers. Depending on the manufacturer, the number of digits varies, but they mean the same thing. For example, there is this type of marking: PPE-1 1.5-3.5 or PPE-2 4.5-12. In this case, the number immediately following the letters indicates the case type. "1" is set if the body is an ordinary cone, on the surface of which grooves can be applied - for a better grip. If there is a PPE-2, then there are small protrusions on the case, which are convenient to take with your fingers and twist.

All other figures reflect the total cross section of all conductors that can be connected using this particular PPE cap.

For example, PPE-1 2.0-4.0. This means that the body of the connecting cap is ordinary, cone-shaped. With it, you can connect two conductors with a cross section of at least 0.5 mm 2 (in total they give 1 mm, which corresponds to the minimum requirements - see table). Maximum conductors are included in this cap, the total cross section of which should not exceed 4 mm 2.

Connecting wires using PPE caps

In the second marking option, after the PPE abbreviation, there is only a number from 1 to 5. In this case, you just need to remember which one is useful for which wire section. The data is in another table.

PPE caps and their parameters

By the way, only copper wires can be connected with PPE caps - aluminum conductors, as a rule, are thicker than the maximum allowable for these connectors.

Bolted connection

This connection is assembled from a bolt of any diameter, a suitable nut and one, or better three, washers. It assembles quickly and easily, serves quite a long time and is reliable.

First, the conductors are stripped of insulation, if necessary, the upper oxidized layer is removed. Further, a loop is formed from the cleaned part, the inner diameter of which is equal to the diameter of the bolt. To make it easier, you can wrap the wire around the bolt and twist it (the middle option in the right picture). After all this is assembled in this order:

• A washer is put on the bolt.
• One of the conductors.
• Second puck.
• Another conductor.
• Third puck.
• Screw.

The connection is tightened first by hand, then with the help of keys (you can take pliers). That's all, the connection is ready. It is used mainly if it is necessary to make a connection of wires from copper and aluminum, it can also be used when connecting conductors of different diameters.

How to connect aluminum and copper conductors

By the way, let us recall why it is impossible to directly connect copper and aluminum wires. There are two reasons:

• Such a connection is very hot, which in itself is very bad.
• Over time, contact weakens. This is because aluminum has a lower electrical conductivity than copper, and as a result, when the same currents are passed, it heats up more. When heated, it expands more, squeezing out the copper conductor - the connection gets worse, it heats up more and more.

To avoid such troubles, copper and aluminum conductors are connected using:

• terminal blocks;
• wago;
• bolted connection;
• branch clamps (make wire connections on the street).

Other types of connectors cannot be used.

How to connect wires of different diameters

If it is necessary to connect conductors having different diameters, twisting must not be present to obtain good contact. So you can use the following types:

• terminal blocks;
• wago;
• bolted connection.