Connecting wires - methods of reliable ways to connect wires of different types, types and sections (120 photos). Connecting electrical wires - reliable methods Connecting two wires with a clamp

Not only the reliability of the power supply, but also the safety of housing depends on the quality of the wire connection. Damage to the wiring occurs due to poor contact at the connection point, as a result of which it burns out, and in the worst case, causes a fire.

The method of connecting wires is selected depending on:

• Wire material.
• Sections of veins.
• Wiring operating conditions.
• Number of conductors.

All connections are made according to the diagram in the distribution box, which is installed in a hidden or open way.

Connection with terminal blocks

The terminal block design consists of a plastic housing, inside of which there are brass tubes with threaded holes on both sides. The diameter of the inlet holes of the tubes varies and is selected depending on the cross-section of the wire.

The process of connecting wires in this way does not cause difficulties even for beginners:

• Select a block with the required cell size.
• Cut off required amount sections.
• Remove 5 mm of insulation from the conductors and clean the surface of the conductors.
• Insert the ends of the wires inside the cells and secure by tightening the screws.

The last procedure is carried out with force, especially if aluminum conductors are used. If too much force is applied, the screw will crush the aluminum core, the same applies to stranded wires - thin wires are deformed under the action of the screw, making the connection unreliable.

This problem is solved by special lugs that are placed on the bare ends of the wires, crimped with press jaws or pliers, and then inserted into the cells of the terminal blocks. For connecting aluminum or stranded conductors Terminal blocks made of high-strength plastic are also used, in which the conductor is clamped not with a screw, but with a plate, thereby achieving reliable contact. The devices are designed to operate with higher current.

Advantages of terminal blocks:

• Low cost.
• Quick installation.
• Good connection quality.

Flaws:

1. There are many poor quality products on sale.
2. You cannot connect more than two conductors.

Terminal blocks are convenient to use for connecting chandeliers, sockets, switches, as well as joining wires broken in the wall, but such a connection cannot be hidden under a layer of plaster, but only in a junction box.

Spring terminals

The design of spring terminals was developed by the German company WAGO. The principle of their operation is that the conductors are clamped not with a screw, as in conventional terminal blocks, but with a lever-type mechanism that fixes the conductors without deforming them.

WAGO terminal housings are made of polymer materials. The contact part consists of two brass plates, one is rigidly fixed, and the second is movable. Simply insert the bare end of the wire into the terminal cell and lower the locking flag.

There are two types of WAGO spring pads:

• Detachable.
• One-piece.

Detachable terminals are reusable - the connection can be disassembled and reassembled. Permanent terminals are used only once. To repair the wiring, you will have to cut off the terminal block and install a new one after fixing the problem.

Advantages of spring terminals:

• Quick installation.
• Connection of more than two conductors.
• Reliable contact without deformation of cores.
• Hole for measuring network parameters.
• You can connect conductors from different materials.

Flaws:

• High cost compared to conventional pads.
• Not recommended for use on heavily loaded networks.

Important. When connecting aluminum wires, it is recommended to pre-fill the terminal with contact paste to prevent oxidation of the wires. WAGO's product range includes terminals that have already been treated with this product during manufacture.

PPE caps

The design of connecting insulating clamps (PIC) consists of a cap and a cone spring inserted inside it. The cap is made of heat-resistant plastic that can withstand voltages up to 660 V.

Connecting wires with PPE caps is done in two ways - with and without preliminary twisting of the cores. When connecting two conductors, it is enough to attach their bare ends to each other, put on the cap and twist it with clockwise rotational movements. Connecting three or more wires with a PPE cap is done by twisting their ends with pliers. The insulation from the cables is removed so that the exposed part does not protrude beyond the cap - additional insulation is not required.

Advantages of PPE caps:

• Low cost connectors.
• Quick installation.
• PPE is made of non-flammable material.
• The caps have different colors, which makes it possible to mark the wiring.

Flaws:

• Do not connect copper conductors to aluminum ones.
• Relatively weak fixation and insulation.

To make the connection reliable, it is important to choose desired type clamp All PPE caps are marked, which first indicates the type of body: 1 - without a protrusion, 2 - with a protrusion for more convenient grip of the cap with your fingers. After the housing type, the minimum and maximum total cross-section of the cores that can be connected in the clamp is indicated.

Crimping with sleeves

The most reliable connection used in lines with high current load. A tube is used as a clamp, into which the bare ends of the conductors are inserted and crimped with mechanical or hydraulic press pliers. Some craftsmen use pliers for this purpose, but in this case the reliability of the connection cannot be guaranteed.

The material of the sleeve must match the material of the conductors. If it is necessary to connect a copper cable to an aluminum cable, use a combined copper-aluminum sleeve. The diameter of the tube is selected depending on the total cross-section of the conductors - after inserting the ends, there should be no voids left in it.

The connection of the wires by crimping is done so that their ends are approximately in the middle of the sleeve. The connection is insulated with heat shrink tubing or ordinary electrical tape.

Advantages of crimping with sleeves:

• Low cost of sleeves.
• Reliable connection with high mechanical strength.
• You can combine copper with aluminum.

Flaws:

• Permanent connection - if necessary, the sleeve will have to be cut off.
• Needed for work special tool.
• The work requires more time.

Important. Copper and aluminum are susceptible to oxidation. Before crimping, it is recommended to clean the wires to a shine and treat them with a special lubricant.

Soldering and welding

Soldering is an old but reliable method that is still used today. Its essence is to connect wires with molten solder, which flows into the twist gaps. After it hardens, a monolithic compound is formed. Soldering is used to join copper wires. There are also fluxes for aluminum on sale, but experts prefer to refrain from soldering it. Soldering process:

1. Remove the insulation from the ends of the wires and remove any varnish.
2. Make a twist.
3. Treat the twist with rosin.
4. Heat the joint with a soldering iron and solder until it fills all the gaps.
5. Let cool.
6. Treat the soldering area with alcohol and insulate it.

This method is well suited for joining conductors of small diameters. The resulting connection does not require maintenance throughout its entire service life.

Advantages of soldering:

• Excellent connection quality.
• Low cost of work.

Flaws:

• Labor intensity.
• Experience with a soldering iron is required.
• Permanent connection.
• Cannot be used in networks with high current load.

To connect cables by welding, a welding machine is used. As in the previous case, the ends of the conductors are pre-twisted, then the end of the twist is fused with a carbon or graphite electrode until a ball is formed. The result is a monolithic connection that is reliable. The disadvantages of this method are the permanent connection and the need for certain welding skills.

Stranding and insulation

The idea is to twist the bare ends of the conductors together with pliers and then insulate them. Until recently, when the load in apartments consisted only of lighting and TV, twisting was used everywhere. Now it is prohibited by PES, especially in wooden buildings and rooms with high humidity.

Advantages of twisting:

• Ease of operation.
• No material costs required.

Flaws:

• Poor connection quality.
• Copper cannot be combined with aluminum.

Preparatory stage for soldering or welding, when installing temporary wiring.

Connecting wires with walnut clamps

Branch clamp is designed to make branches from the main cable without breaking it. The clamping device consists of a collapsible polycarbonate body; inside there is a steel core of two dies and an intermediate plate. The body halves are connected to each other by retaining rings, and the dies are connected by coupling bolts.

Branch compressor installation:

1. Disassemble the branch compressor.
2. Remove the insulation from the main wire to the length of the plate.
3. Strip the end of the outgoing wire to the length of the plate.
4. Place the wires in the grooves on the dies.
5. Tighten the core with bolts, first placing a brass plate between the dies.
6. Assemble the body.

Important. It is necessary to choose the correct standard size of the “nut”, depending on the cross-section of the cables used. The selection of compressions is carried out in accordance with the range of sections indicated on the core plates.

Benefits of nut compression:

• Low cost.
• Easy to install.
• Possibility of connecting aluminum and copper.
• Good insulation.

Flaws:

• Large dimensions of the device.
• It is necessary to periodically tighten the bolts.

The device can be used in networks with voltages up to 660 V. The body of the “nut” has fairly good insulation, but is not able to provide complete protection from moisture and dust. When using compression in unfavorable conditions, it is recommended to wrap the body with electrical tape.

Bolt connection

All you need for the job is any bolt, washers of the appropriate diameter and a nut.

The ends of the conductors are stripped of insulation. In exposed areas, loops are formed along the diameter of the bolt. To make work easier, the ends of the cables can be wrapped around the bolt and then tightened. The connection elements are put on the bolt in the following order:

1. Washer.
2. Conductor.
3. Washer.
4. Conductor.
5. Washer.
6. Screw.

The nut is tightened by hand, then with a wrench or pliers. The finished connection is carefully insulated.

Advantages of bolted connection:

• Ease of operation.
• Reliable contact.
• Low cost.
• Demountable connection.
• Use in networks with high load.

Disadvantages: bulky design, which cannot always fit into a junction box, high consumption of electrical tape.

How to connect multiple wires

The following methods are suitable for combining wires:

1. Spring terminals.
2. Twisting with soldering, welding or using PPE caps.
3. Crimping with sleeves.
4. Bolted connection.

The first option is less labor-intensive and the fastest. A bolted connection is also suitable - the number of conductors is limited only by the length of the bolt, but the connection has large dimensions.

Connecting wires of different sections

When connecting conductors of different cross-sections, twisting cannot ensure reliable contact, so all methods associated with it are excluded. It is recommended to use terminal blocks, spring terminals or bolt connection.

Combining stranded and solid conductors

Doesn't have any special features. Any of the described methods will do, with the only exception being twisting of conductors from different materials. Otherwise, the choice depends on preferences and financial capabilities. When using screw terminal blocks, it is necessary to have lugs on the stranded wire.

Connecting cables in water and underground

Electricity and moisture are incompatible things, therefore for connections made under water or in the ground, special requirements. The ends of the conductors are connected by soldering or crimping with sleeves. Then they are treated with hot melt adhesive and insulated with heat shrink tube. If everything is done correctly, then moisture penetration into the joint is excluded.

You can also use terminal block connections. The connection point is placed in a sealed box and filled with silicone sealant. The cable running underground must be placed in a pipe or box to prevent damage by rodents.

You can use one method or several at once - it all depends on the installation. The main thing that should not be forgotten is safety. The area where electrical installation work is carried out must be disconnected from the network, adhere to the operating instructions and use a working tool.

In a field such as electricity, all work must be carried out strictly, accurately and without a single mistake. Some people want to figure out such work on their own, not trusting third parties to carry out a responsible mission. Today we will talk about how to properly connect wires in a junction box. The work must be done efficiently, because not only the performance of electrical appliances in the house, but also the fire safety of the premises depends on it.

About the distribution box

In an apartment or house, the wires are routed from the electrical panel according to different rooms. There are usually several connection points: switch, sockets, and so on. In order for all the wires to be collected in one place, distribution boxes were created. They carry wiring from sockets, switches and are connected in a hollow housing.

So that during repairs you do not have to look for where the wires are hidden in the walls, electrical wiring is laid on the basis of special rules prescribed in the PUE (Electrical Installation Rules).

Distribution boxes are classified according to the type of fastening. So, there are boxes for external mounting and indoor installation. For the second option, you need to prepare a hole in the wall into which the box will be inserted. As a result, the box lid is located flush with the wall. Often the cover is hidden with wallpaper or plastic during repairs. As a last resort, an outer box is used, which is attached directly to the wall.

There are round or rectangular junction boxes. In any case, there will be at least 4 exits. Each outlet has a fitting or thread to which a corrugated tube is attached. This is done to quickly replace the wire. The old wire is pulled out and new wiring is laid. It is not recommended to lay the cable in a groove on the wall. If the electrical wiring burns out, you will have to dig into the wall and disturb the finish in order to carry out repair work.

What are distribution boxes for?

There are many factors that speak in favor of the existence of junction boxes:

• The power system can be repaired in a matter of hours. All connections are accessible, you can easily find the area where the wires have burned out. If the cable was laid in special channels (corrugated tube, for example), then the failed cable can be replaced in an hour;
• Connections can be inspected at any time. As a rule, wiring problems occur at the connection points. If the socket or switch does not work, but there is voltage in the network, first check the quality of the connection in the junction box;
• is created highest level fire safety. It is believed that dangerous places are connections. Using a box will keep them in one place.
• minimal time and financial costs when repairing wiring. There is no need to look for broken wires in the walls.

Connecting the wires in the box

There are several ways in which conductor connections can be made in junction boxes. Note that there are simple and complex methods, however, if executed correctly, all options will ensure the reliability of the electrical wiring.

Method number 1. Twisting method

It is believed that the twisting method is used by amateurs. At the same time, this is one of the most reliable and proven options. PUE do not recommend using twisting, since the contact between the wires is unreliable. As a result, the conductors may overheat, putting the room at risk of fire. However, twisting can be used as a temporary measure, for example, when testing an assembled circuit.

Read also:

Experts say that even with a temporary connection of wires, all work must be performed according to the rules. It is worth noting that regardless of the number of cores in the conductor, the twisting methods are approximately the same. However, there are some differences. If multi-core wires are connected, then you should adhere to the following rules:

— it is necessary to clean the conductor insulation by 4 cm;

— untwist each conductor by 2 centimeters (along the veins);

— a connection is made to the junction of untwisted cores;

— you only need to twist the wires with your fingers;

— ultimately, the twist is tightened using pliers and pliers;

- exposed electrical wires are covered with insulating tape or heat shrink tubing.

It is much easier to use twisting when connecting solid wires. After the conductors have been stripped of insulation, they must be twisted by hand along their entire length. Then, using pliers (2 pieces), the conductors are clamped: with the first pliers at the end of the insulation, and with the second at the end of the connection. We increase the number of turns on the connection with the second pliers. The connected conductors are insulated.

Method number 2. Mounting caps - PPE

Very often, special caps are used for twisting conductors. As a result, it is possible to obtain a reliable connection with good contact. The outer shell of the cap is plastic (the material is not flammable), and inside there is a metal part with a cone-shaped thread. The insert increases the contact surface, improving the electrical parameters of twisting. Most often, thick conductors are connected using caps (no soldering required).

It is necessary to remove the insulation from the wire by 2 centimeters, slightly twist the wires. When the cap is put on, it must be turned with force. At this point the connection can be considered ready.

Before making the connection, you need to count the number of wires. Based on the data obtained (cross-section), a specific type of cap is selected. The advantages of twisting using plastic caps are that you do not need to spend a lot of time, as with conventional twisting. In addition, the connection is compact.

Method No. 3. Connecting conductors by soldering

If you have a soldering iron on your household and you know how to work with it, then the wires can be connected by soldering. Before connecting the wires, they need to be tinned. Soldering flux or rosin is applied to the conductor. Next, the heated tip of the soldering iron is immersed in rosin and passed along the wire several times. A reddish coating should appear.

After the rosin dries, the wires are twisted. Using a soldering iron, tin is taken and the twist is heated until tin flows between the turns. The end result is a high-quality connection with excellent contact. However, electricians are not very fond of using this connection method. The fact is that it takes a lot of time to prepare. However, if you are doing the work for yourself, you should not spare any effort or time.

Method number 4. Welding cores

Using an inverter welding machine, you can connect wires. Welding is used over twisting. You need to set the welding current parameters on the inverter. There are certain standards for different connections:

- conductor with a cross section of 1.5 sq. mm - 30 A;

- conductor with a cross section of 2.5 sq. mm - 50A.

If the conductor is copper, then a graphite electrode is used for welding. The grounding from the welding machine is connected to the upper part of the resulting twist. An electrode is brought from below the twist and an arc is ignited. The electrode is applied to the twist for a couple of seconds. After some time, the connection will cool down, then it can be insulated.

Read also: Hidden electrical wiring in a wooden house

Method No. 5. Terminal blocks

Another option for connecting conductors in a box is using terminal blocks. There are several types of pads: screw, with clamps, but the principle of the device is identical. The most common is a block with a copper plate for attaching wires. By inserting several wires into a special connector, they can be reliably connected. Installation using a clamp terminal makes the connection very simple.

In screw terminals, the terminal blocks are placed in a plastic housing. There are open and closed types of pads. Closed pads are a new generation invention. To make a connection, wires are inserted into the socket and clamped with a screw (using a screwdriver).

However, terminal connections have a disadvantage. It lies in the fact that it is inconvenient to connect several conductors together. The contacts are arranged in pairs. And if you need to connect more than three wires, then several branches are squeezed into one socket, which is very difficult. At the same time, such connections make it possible to operate branches with high current consumption.

Another type of terminals is Wago terminals. Today two types of terminals are in demand:

— terminals with a flat-spring mechanism. Sometimes they are called disposable, since it is impossible to reuse the terminals - the quality of the connection deteriorates. Inside the terminal there is a plate with spring petals. As soon as the conductor is inserted (it should only be single-core), the petal is pressed out and the wire is clamped. The conductor cuts into the metal. If you pull out the conductor by force, then the petal will not take its previous shape.

Some terminal connections contain wiring paste inside. This connection is used if you need to connect copper and aluminum wires. The paste protects metals from oxidation, protecting conductors;

- universal terminals with a lever mechanism - this is the best type of connector. The wire, stripped of insulation, is inserted into the terminal and a small lever is clamped. At this point the connection is considered complete. And if you need to reconnect, add contacts, lift the lever and pull out the wire. The pads can be operated at low current (up to 24 A - with a cross-section of 1.5 sq. mm) and at high current(32 A - with a conductor cross-section of 2.5 sq. mm). If wires are connected through which a current higher than that specified will flow, then a different type of connection must be used.

Method number 6. Crimping

The wires in the box can only be connected by crimping using special pliers and a metal sleeve. A sleeve is put on the twist, after which it is clamped with pliers. Just this method Suitable for connecting conductors with heavy loads.

Method No. 7. Bolted connection

Connecting multiple wires using bolts is easy and effective method connections. To complete the work, you need to take a bolt and several washers with a nut.

It is not enough to know how to connect the wires in a junction box. You need to know which conductors are connected to each other. So, a washer is put on the bolt thread. The core is screwed on, the second washer is put on, and then the next core is put on. At the end, put on the third washer and press the connection with a nut. The node is closed with insulation.

There are several advantages of bolted connection of conductors:

- ease of work;

- low cost;

- the ability to connect conductors made of different metals(eg aluminum and copper).

However, there are also disadvantages:

— fixation of wires is not of high quality;

- to hide the bolt you need to use a lot of insulation;

Electricity is not an area where you need to save. It is advisable to do everything carefully, select high-quality materials, and take a balanced approach to the choice of sizes/diameters/values. Let's start with the fact that even the conductors must be connected correctly. And choosing ways 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 do not require any special skills.

The first group includes:

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

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

Some methods of connecting wires are more popular, others less so.

Methods of connecting wires that do not require any specific skills are becoming increasingly popular. Their advantage is quick installation and reliable connection. Disadvantage - you need “connectors” - terminal blocks, clamps, bolts. Some of them cost quite a lot of money (Wago terminal blocks, for example), although there are also inexpensive options- screw terminal blocks.

So here are ways to connect wires that are easy to implement:

There are two opposing opinions among professionals. Some believe that new methods of connecting wires - clamps - are the best solution, as they speed up installation without compromising the quality of the connection. Others say that the springs will eventually weaken and 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 the specific type is selected based on several characteristics:

Let's consider each connection method, the technology for its implementation and the advisability 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, that's the end of the soldering electrical wires finished. Not the most difficult process but it requires certain skills. The main thing is to heat the joint enough so that the solder flows between all the wires. In this case, you must not overheat, otherwise the insulation will melt. This is where the art lies - not to burn the insulation, but to ensure reliable contact.

When can soldering be used? This method of connecting wires works well in low-current electrical applications. 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 make a connection in a junction box, the soldering begins to break down. To the point where some 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 methods of connecting wires is welding. During this process, the metal of individual conductors is brought to the melting point, mixed, and after cooling it forms a monolith. This method works very well with large diameters or with a large number of connected conductors. It is distinguished by not just excellent contact, which does not weaken or change its characteristics over time. It is also mechanically very strong - the fused part does not allow the connection to fall apart even under heavy loads.

A drop at the end of the twist is molten aluminum

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

Another disadvantage of welding wires is that it is a labor-intensive process, which also requires jeweler's precision in handling the welding machine. Due to the combination of these qualities, many professional electricians do not like this method. If you do the wiring “for yourself” and know how to handle the equipment, you can spend some time. Just practice first on scraps, select the current strength and welding time. Only after you get everything perfect several times can you start welding wires “in real life”.

Crimping

Another method that requires special equipment is crimping wires with sleeves. There are copper and aluminum sleeves of 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 the entire space inside the sleeve, but there should still be free space. The quality of contact depends on the correct choice of sleeve size. This is the main difficulty with 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 longer sleeves).
• Each conductor is stripped to pure metal(remove oxides with fine-grain sandpaper).
• The wires are twisted and inserted into the sleeve.
• They are crimped with special pliers.

It seems to be simple, but it is in the selection of the sleeve and the presence of pliers that the whole difficulty lies. You can, of course, try to crimp it with pliers or pliers. But it is impossible to guarantee normal contact in this case.

Twist

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

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

Why is twisting so bad? Wires twisted into a bundle do not make good enough contact. At first, everything is fine, but over time the metal becomes covered with an oxide film, which significantly worsens the contact. If there is insufficient contact, the joint begins to heat up; an increase in temperature causes more active formation of an oxide film, which further worsens the contact. At some point, the twist becomes very hot, which can lead to a fire. It is for this reason that it is better to choose any other method. There are some that can be done even faster and easier, but which are more reliable.

Connection insulation

All the methods of connecting wires described above - welding, soldering, crimping with a sleeve - provide for their insulation, since the exposed conductors must be protected. For these purposes, electrical tape or heat-shrinkable tubes are used.

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

Heat-shrinkable tubes for insulating conductors can be of different diameters and colors

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

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

The cost of heat-shrinkable tubes 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 edge of the tube stretches over the insulation of the conductors by about 0.5 cm, and the other 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. The heating temperature can be different - from 60°C to +120°C. After the joint is tightened, the heating stops, after which the polymer quickly cools.

Insulating wires with heat-shrinkable tubing takes little time—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 one tube is put on and warmed up, then the second. Such connections can be used even in water.

Terminal blocks

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

Terminal blocks are a contact plate that is sealed in a plastic (polymer) or carbolite housing. They cost very little and are available in almost any store that sells electrical goods.

Terminal blocks are convenient, inexpensive, allow you to connect copper and aluminum wires, conductors of different diameters, single- and multi-core

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

The advantage of this connection method: you can connect wires of different sections, single-core to multi-core. The disadvantage is that only a pair of wires are connected. To connect three or more, jumpers must be installed.

PPE caps

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

Connecting wires using PPE is very simple: strip the insulation, collect the wires into a bundle, insert them inside the cap and start twisting. A spring inside the cap grips the conductors, helping to twist them. The result is a twist that outside wrapped with spring wire. That is, the contact turns out to be 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 insulation from the wires. Manufacturers give clear instructions on this matter - each size has its own length of exposed conductors. It is designed so that all conductors without insulation are inside the housing. 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 interfere with heat dissipation and such a connection heats up less.

Practicing electricians advise stripping the wires by 5-10 cm, and insulating the twist that remains 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 is reliable. There are no problems with contact (if the quality of PPE is normal).

Wago Clamps

The heated debates flared up specifically about Vago. Some people absolutely love this product, while others don’t. Moreover, no less categorically. Opponents of using the Wago don't like the fact that the contact is based on a spring. They say that it may weaken. This will lead to poor contact and overheating. And they show a photo with melted clamps. Proponents of this method conduct tests and comparisons and say that a properly selected branded clamp lasts for many years without signs of contact deterioration. And manufacturers say that, if the technology is followed, 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 single-core 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 high cost. In any case, contact is ensured by a contact plate made of good copper. The special shape of the plate allows for reliable contact.

Detachable

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

We repeat the same operation with the other wire(s). All this takes a matter of seconds. Very fast and convenient. It's not surprising that 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). The housing has holes into which wires stripped of insulation are inserted.

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

Bolted connection

Another type of connection of electrical wires with 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 quite good, but the entire structure takes up a lot of space and is inconvenient to install. It is mainly used if it is necessary to connect conductors made of different metals - aluminum and copper.

The order of assembling the connection is as follows:

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

This way you can connect not only two, but also three or more wires. Please note that you must not only tighten the nut by hand. Must be used spanners, make a solid effort.

The best ways to connect wires for different occasions

Since different wires can be connected, they can be used in different conditions, That the best way you need to choose taking into account all these nuances. Here are the most common situations:

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

To ensure that the power supply in your homes is always of high quality, uninterrupted and reliable, it is very important to correctly connect the wires during installation work. There are a lot of methods, we will consider each in detail separately with its advantages and disadvantages, with step by step instructions perform 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

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

This can be done using a mechanic's knife. This method is simple, but there is a high probability of damage to the conductor. To do everything correctly, you must strictly follow the step-by-step instructions:

1. Place the wire on some flat surface(type of table).
2. Press it with your left index finger.
3. Right hand take a knife and lightly press it into the insulating sheath of the wire. To avoid snagging the metal core, position it towards the cut at an angle. If the angle is right, there is a possibility of a circular cut in the core, as a result of which it may subsequently break.
4. Hold the knife in this position. Using the index finger of your left hand, slowly twist the conductor one full turn, thus cutting the insulation around the entire circle.
5. All that remains is to pull off the cut piece of insulation.

Professional electricians now necessarily have in their arsenal such a device as a stripper. This multifunctional tool, you can use it to remove insulation from a wire or cut a cable. It can be simple, semi-automatic or automatic. The most important thing is that when stripping the insulation with a stripper, the conductor is not damaged. For each standard core diameter, such a tool has a calibrated hole with a cutting edge.

The length to which wire cores need to be stripped is different for each connection method.

Twist

Let's start with the simplest and most well-known method - twisting. It can also be called the oldest; it’s not for nothing that electricians call twisting the “old-fashioned method.”

We will not tell you that such a connection of wires 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 television. Considering what the current load is in modern apartments With a huge number of household appliances used daily, then no old insulation, core cross-sections and methods of connecting wires are any longer suitable.

Nevertheless, we will talk about twisting, and even first of all, because it is the main stage of 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 cores and pliers to make the connection.

The second indisputable advantage of twisting is its ease of execution. You don’t need any special knowledge or skills; it can be done by anyone who has ever held pliers in their hands.

Several wires can be connected simultaneously in a twist, 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 residual elastic deformation in the cable or wire cores. At the point of twisting, the contact resistance increases, which can lead to contact failure and heating. IN best case scenario, you will detect this in time and re-seal the connection; in the worst case, a fire may occur.

Electrical wires made of different metals cannot be connected using twisting. As an exception, you can twist copper and aluminum wire, but only if the copper core is first tinned with solder.

In electrical engineering there are concepts of detachable or permanent connection. So twisting does not apply to one or the other. A detachable connection is characterized by the fact that its ends can be disconnected many times. This cannot be fully done in twisting; every time after the next unwinding and twisting of the cores, they will deteriorate. It is also impossible to call twisting a permanent connection, because it does not contain the concepts of strength, reliability and stability necessary for this. This is another disadvantage of the twist connection.

Installation

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 well. Very often it is used as a temporary option and is subsequently replaced by more in reliable ways switching

How to connect wires using twist? To begin with, the cores are stripped to 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 people mistakenly begin to twist the wires together from the place where the insulating layer ends. But it’s better to clamp both wires in this place with one pliers, and grab the ends of the wires with the second and make rotational movements in a clockwise direction.

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

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

How to properly twist wires is shown in this video:

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

For information on twisting wires using a special tool, see here:

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

You can also insulate the connection of wires using heat pipes. The main thing is not to forget to put the tube on one of the cores to be connected in advance, and then push it into the place where it is twisted. When exposed to heat, the thermal tube shrinks, so slightly heat its edges and it will firmly grip the wire, thereby providing reliable insulation.

If the twisting is done well, there is a chance that it will serve you for many years, provided that the load current in the network is normal. But it’s still better not to stop at this stage and strengthen the joint by welding or soldering.

Soldering

Soldering is when electrical wires are joined 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 and aluminum.

Positive sides

This type of connection cannot be compared with twisting; soldering is much more reliable (in terms of reliability it is second only to welding).

Using soldering, you can connect stranded and single-core wires, as well as wires of different sections.

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

Soldering is considered low in cost, the only equipment you need is a soldering iron, and flux and solder are very inexpensive, and their consumption is quite negligible.

Negative sides

The disadvantages of this method include high labor intensity. Soldering requires certain preparatory work; wire strands must first be tinned before twisting. The surfaces to be soldered must be free of oxides and absolutely clean before starting work.

And of course, you need experience in using a soldering iron, that is, the person who will connect the wires using the soldering method must have a certain qualification. Indeed, during the soldering process it is very important to maintain the necessary temperature regime. An underheated soldering iron will not heat the connection well; overheating is also unacceptable, because the flux will burn out very quickly, not having time to do its job.

Soldering is a slow process, but this disadvantage is compensated by the reliability of the contact connection.

Installation

The step-by-step soldering process is as follows:

1. Remove the insulation from the cores by 40-50 mm.
2. Sand the bare areas of the wires until they shine using sandpaper.
3. Dip a heated soldering iron into rosin and move it over the cleaned surfaces several times.
4. Perform a twist.
5. Bring the soldering iron tip 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 the hardened solder with alcohol and insulate it.

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

Soldering wires using 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 twisting method must be subsequently secured 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 to all others, since it meets all regulatory requirements in terms of reliability and quality.

The welding method is based on 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 unit from the fused ends of all connected cores, which ensures safe and reliable contact; it will not weaken or oxidize over time.

Negative sides

The disadvantage of welding is that such work requires certain knowledge, experience, skills and special equipment; you often have to turn to specialists.

Installation

In order to connect wires using welding, you will need the following devices, 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;
• goggles or eye mask;
• welding leather gloves to protect hands;
• a mechanic's knife or stripper for removing the insulating layer from conductors;
• sandpaper (for cleaning the conductive surfaces to be connected);
• insulating tape for further insulation of the welding joint.

The sequence of work is as follows:

1. Free each connected wire from 60-70 mm of insulation.
2. Sand the exposed wires until they are shiny using sandpaper.
3. Twist, after biting, the length of its ends should be at least 50 mm.
4. Attach grounding clamps to the 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 happens very quickly.
6. It turns out to be a contact ball, give it time to cool, and then insulate it 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 (it will be useful not only for connecting wires, but also for many other purposes), then choose the inverter option. With small dimensions, weight and consumption electrical energy, 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 you choose it correctly, the electrode will not stick and the arc will hold steady.

Watch how welding is done in this video:

We looked at the main types of wire connections. Now let’s briefly talk about methods that are used less frequently, 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 is the joint deformation of the sleeve and the cores inserted into it. When deformed, the sleeve contracts and puts pressure on the conductive surfaces. The conductors engage in mutual adhesion, which ensures reliable electrical contact.

The advantage of such a connection is its reliability, and also the fact that it can be classified as “set and forget”; it does not require maintenance.

But along with positive aspects Crimping also has a number of disadvantages. First, a special tool is required (a crimping press 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 cores being connected 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 appearing again. For copper conductors, quartz impurities are not needed; technical petroleum jelly is sufficient. It is needed to reduce friction. Lubrication also minimizes the risk of damage to the cores during deformation.

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

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 characteristic of circuits with high voltage. The contact is reliable, but the electrical unit connected in this way is too cumbersome. Until recently, large distribution boxes were installed in apartments; at least somehow, such a connection could be placed in them. Modern boxes are smaller and are not designed for switching wires using this method.

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 different metals. The bolt contact is ideal for switching completely incompatible cores - thin and thick, aluminum and copper, single-core and stranded.

The wire strands must be stripped and the ends twisted into rings. A steel washer is put on the bolt, then the rings of the wires to be connected are put 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, another additional washer must be placed between them.

The advantages of this connection are its simplicity. If necessary bolted structure You can always unwind. If necessary, you can add more wire strands (as long as the bolt length allows).

The most important thing in this type of connection is to prevent direct contact between copper and aluminum, and do not forget to place an additional washer between them. And then such a switching unit will serve for 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 made installation and switching work much easier and faster:

1. Terminal blocks, inside of which there are tubular brass sleeves. Stripped wire strands are inserted into these tubes and secured by tightening the screws.
2. PPE caps, inside of which there are compression springs. The cores are inserted into the cap and then turned clockwise with little effort, thereby reliably compressing the connected wires 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. This connecting element is reusable. It is enough just to lift the lever, insert the conductor into the contact hole and lower the lever back, reliable fixation is ensured.

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

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), and the amount of load current that will flow in this electrical circuit.

All electrical engineering, since the time of Faraday, uses wires. And for as many years as wires have been used, electricians have been faced with the problem of connecting them. This article explains what methods there are for connecting conductors, and the advantages and disadvantages of these methods.

Twist connection

The easiest way to connect wires is twisting. Previously, this was the most common method, especially when wiring in a residential building. Now, according to the PUE, connecting wires in this way is prohibited. The twist must be soldered, welded or crimped. However, these methods of connecting wires begin with twisting.

In order to perform high-quality twisting, the connected wires must be cleared of insulation on required length. It ranges from 5 mm when connecting wires for headphones to 50 mm if it is necessary to connect wires with a cross-section of 2.5 mm². Thicker wires are usually not twisted together due to their high rigidity.

Wires are stripped sharp knife, insulation stripping pliers (ISR) or, after heating with a soldering iron or lighter, the insulation is easily removed with pliers or side cutters. For better contact, bare areas are cleaned with sandpaper. If the twist is supposed to be soldered, then it is better to tin the wires. Wires are tinned only with rosin and similar fluxes. This cannot be done with acid - it corrodes the wire and it begins to break at the soldering site. Even washing the soldering area in a soda solution doesn’t help. Acid vapors penetrate under the insulation and destroy the metal.

The stripped ends are folded parallel into one bundle. The ends are aligned together, the isolated part is held firmly with your hand, and the entire bundle is twisted with pliers. After this, the twist is soldered or welded.

If there is a need to connect the wires to increase the total length, then they are folded opposite each other. The cleaned areas are placed crosswise on top of each other, twisted together by hand and tightened tightly with two pliers.

You can only twist wire made of the same metal (copper with copper, and aluminum with aluminum) and of the same cross-section. Twisting wires of different sections will turn out uneven and will not provide good contact and mechanical strength. Even if it is soldered or crimped, these types of wire connections will not ensure good contact.

How to connect electrical wires by soldering

Connecting electrical wires by soldering is very reliable. You can solder untwisted wires, but such soldering will be fragile due to the fact that the solder is a very soft metal. In addition, it is very difficult to lay two conductors parallel to each other, especially when suspended. And if you solder on some kind of base, the rosin will stick the soldering area to it.

A layer of rosin is applied to the pre-tinned and twisted conductors with a soldering iron. If another flux is used, it is applied in the appropriate manner. The power of the soldering iron is selected based on the cross-section of the wire - from 15 W when soldering headphones to 100 W when soldering twisted wires with a cross-section of 2.5 mm². After applying the flux, tin is applied to the twist with a soldering iron and heated until the solder completely melts and flows into the twist.

After the soldering has cooled, it is insulated with electrical tape or a piece of heat-shrinkable tubing is put on it and heated with a hairdryer, lighter or soldering iron. When using a lighter or soldering iron, be careful not to overheat the heat shrink.

This method reliably connects wires, but is only suitable for thin wires, no more than 0.5 mm², or flexible ones up to 2.5 mm².

How to connect headphone wires

Sometimes the cable near the plug breaks off in working headphones, but there is a plug from faulty headphones. There are also other situations in which it is necessary to connect the wires in the headphones.

To do this you need:

1. cut off a broken plug or an unevenly torn cable;
2. strip the external insulation by 15–20 mm;
3. determine which of the internal wires is common and check the integrity of all conductors;
4. trim internal wiring according to the principle: do not touch one, common by 5 mm and the second by 10 mm. This is done to reduce the thickness of the connection. There can be two common conductors - each earphone has its own. In this case they are twisted together. Sometimes a screen is used as a common conductor;
5. strip the ends of the wires. If varnish is used as insulation, it will burn off during the tinning process;
6. tin the ends to a length of 5 mm;
7. put a piece of heat-shrink tubing on the wire 30 mm longer than the expected length of the connection;
8. on long ends put on pieces of thinner heat-shrinkable tube 10 mm long, do not put on the middle (general) one;
9. twist the wires (long with short, and middle with middle);
10. solder the twists;
11. bend the soldered twists outward to the unprotected edges, slide pieces of thin heat-shrinkable tubing onto them and heat it with a hairdryer or lighter;
12. Slide a larger diameter heat-shrinkable tube onto the joint and warm it up.

If everything was done carefully and the color of the tube was matched to the color of the cable, then the connection will be invisible and the headphones will work no worse than new ones.

How to brew twist

For good contact, the twist can be welded with a graphite electrode or gas burner. Torch welding has not become widespread due to the complexity and the need to use gas and oxygen cylinders, so this article only talks about electric welding.

Electric welding is performed using a graphite or carbon electrode. Graphite electrode is preferable. It is cheaper and provides best quality welding Instead of a purchased electrode, you can use a rod from a battery or a brush from an electric motor. It is better not to use copper electrodes. They often get stuck.

For welding, you first need to make a twist 100 mm long, so that the finished one turns out to be about 50. The protruding wires need to be trimmed. For welding, it is best to use an inverter welding machine with adjustable current. If this is not the case, then you can take a regular transformer with a power of at least 600 W and a voltage of 12–24 V.

Near the insulation, “ground” or “minus” is connected using a thick copper clamp. If you simply wrap a wire around a twist, the twist will overheat and melt the insulation.

Before starting welding, it is necessary to select the current. The required current varies depending on the number and thickness of the wire that makes up the twist. The welding duration should be no more than 2 seconds. If necessary, welding can be repeated. If everything was done correctly, then a neat ball will appear at the end of the twist, soldered to all the wires.

How to connect wires by crimping

Another way to connect wires is crimping. This is a method in which a copper or aluminum sleeve is placed on the wires or cables to be connected, and then crimped with a special crimper. For thin sleeves, a manual crimper is used, and for thick ones, a hydraulic one is used. This method can even connect copper and aluminum wires, which is unacceptable with a bolted connection.

To connect using this method, the cable is stripped to a length greater than the length of the sleeve, so that after putting on the sleeve, the wire sticks out 10–15 mm. If thin conductors are connected by crimping, then twisting can be done first. If the cable has a large cross-section, then, on the contrary, in the stripped areas it is necessary to align the wire, fold all the cables together and give them a round shape. Depending on local conditions, the cables can be folded with the ends in one direction or in the opposite direction. This does not affect the reliability of the connection.

A sleeve is tightly placed on the prepared cables or, when laid in opposite directions, the wires are inserted into the sleeve from both sides. If there is still free space in the sleeve, it is filled with pieces of copper or aluminum wire. And if the cables do not fit in the sleeve, then a few wires (5–7%) can be cut off with side cutters. In the absence of a sleeve the right size You can take a cable lug by sawing off the flat part of it.

The sleeve is pressed 2–3 times along its length. The crimping points should not be located at the edges of the sleeve. It is necessary to retreat 7–10 mm from them so as not to crush the wire during crimping.

The advantage of this method is that it allows you to connect wires of different sections and from different materials, which is difficult with other connection methods.

A fairly common connection method is a bolted connection. For this type you need a bolt, at least two washers and a nut. The diameter of the bolt depends on the thickness of the wire. It should be such that a ring can be made from the wire. If wires of different sections are connected, then the bolt is selected according to the largest one.

To make a bolted connection, the end is cleared of insulation. The length of the stripped part should be such as to make a ring that fits onto the bolt using round pliers. If the wire is stranded (flexible), then the length should allow, after making the ring, to wrap the free end around the wire near the insulation.

In this way, you can connect only two identical wires. If there are more of them, or they are different in cross-section, rigidity and materials (copper and aluminum), then it is necessary to install conductive, usually steel washers. If you take a bolt of sufficient length, you can connect any number of wires.

Terminal block connection

A development of the bolted connection is the terminal connection. Terminal blocks come in two types - with a rectangular pressure washer and with a round one. When using a terminal block with a pressure washer, the insulation is removed to a length equal to half the width of the terminal block. The bolt is released, the wire is slipped under the washer and the bolt is clamped again. On one side, you can connect only two wires, preferably of the same cross-section and only flexible or only single-core.

Connecting to a terminal block with a round washer is no different from using a bolted connection.

The connection of the wires is reliable, but cumbersome. When connecting wires with a cross-section of more than 16 mm², the connection is unreliable or the use of lugs is necessary.

Self-clamping terminal blocks WAGO

In addition to terminal blocks with bolts, there are also terminal blocks with clamps. They are more expensive than usual, but they allow the connection to be made much faster, especially in connection with the new requirements of the PUE and the ban on twisting.

The most famous manufacturer of such terminal blocks is WAGO. Each terminal is a separate device with several holes for connecting wires, each of which is inserted into a separate wire. Depending on the version, it connects from 2 to 8 conductors. Some types are filled inside with conductive paste for better contact.

They are available for both detachable and permanent connections.

The stripped wire is simply inserted into the terminals for a permanent connection and spring tendrils fix the wire inside. Only hard (single-core) wire can be used.

In plug-in terminals, the wire is clamped using a folding lever and a spring clamp, making it easy to connect and disconnect wires.

Since the wires do not touch each other, the terminals allow you to connect wires of different sections, single-core to stranded, copper to aluminum.

This method of connecting conductors has proven to work best at low currents and is most widespread in lighting networks. These terminals are small in size and easily fit into adapter boxes.

How to connect electrical wires with lugs

Another way is to use tips. The tip looks like a piece of tube, cut and turned flat on one side. A hole for a bolt is drilled in the flat part. The lugs allow you to connect cables of any diameter in any combination. If it is necessary to connect a copper cable to an aluminum cable, special lugs are used, in which one part is copper and the other is aluminum. It is also possible to place a washer, brass or tinned copper, between the tips.

The ferrule is pressed onto the cable using a crimper, similar to how wires are connected using crimping.

Soldering tips

Another way to use the tip is to solder it. To do this you need:

• stripped copper cable;
• tip designed for soldering. It is distinguished by a hole near the flat part and a thinner wall;
• bath of molten tin;
• a jar of phosphoric acid;
• a jar of soda solution.

Carefully! Wear protective glasses and gloves!

In order to solder the tip, the cable is cleared of insulation along the length of the tubular part and inserted into the tip. Then the tip is successively immersed in orthophosphoric acid, in molten tin for a time sufficient for the acid to boil away and the solder to flow into the tip. This is checked by periodically briefly removing it from the solder. After impregnating the tip and cable with solder, the tip is dipped in a soda solution. This is done to neutralize acid residues. The cooled tip can be washed clean water and ready for further work. Such a tip can be connected to aluminum busbars and lugs without the use of adapter washers.

Connectors for cables and wires

Cables can also be connected using special connectors. These are sections of pipe in which threads are cut and bolts are screwed in. There are detachable connectors, in which the bolts are unscrewed, and permanent ones. In permanent connectors, the bolt heads break off after clamping. There are also connectors designed to connect wires and cables of different sections. The cables are inserted end-to-end into the connectors, facing each other.

Connectors used on overhead power lines consist of two halves connected by bolts. The wires are laid in special grooves towards each other, parallel to each other, after which both halves are clamped with bolts.

Connecting wires and cables using couplings

If the cable to be connected is in the ground, water or rain, then conventional methods of isolating the connection are not suitable. Even if you apply a layer of silicone sealant to the cable and compress it with heat-shrink tubing, this will not guarantee tightness. Therefore, it is necessary to use special couplings.

Couplings are available in plastic and metal case, poured and heat-shrinkable, high-voltage and low-voltage, regular and small-sized. The choice of coupling depends on the specific operating conditions and the presence or absence of mechanical loads.

Connecting wires and cables is one of the most important points during electrical installation. Therefore, all methods of connecting electrical wires must ensure good contact. Poor contact or poor insulation may result in short circuit and fire.

Video on the topic

Power terminal

Soldering wires in headphones