Quick wire connector. Methods for connecting wires to each other

18.10.2023

About 70% of installation errors are related to wires. The lack of electricity may be due to unreliable contact or its absence in the junction box or electrical appliance. Further in the article - all the options for connecting wires, their installation and types.

Methods for connecting wires and cables

Electricity is an area in which you need to carefully select materials and monitor reliability and performance.

For high-quality and uninterrupted power supply in the house, the electrical wires must be connected correctly.

In case of an error, not only the functionality of household appliances will be at risk, but also fire safety.

When to connect cables

Cable connections will be required in case of poor-quality wiring performed earlier, or due to errors made during installation work. To restore power to the house, you need to connect the electrical wires. You can make a connection in ways that are divided into 2 groups:

For the first group, no special equipment is required.
The second group already requires certain skills and professional tools.

Work on connecting cables must be carried out in compliance with safety regulations.

Types of cables for connection

The most common cable for home electrical wiring is a PVA connecting cable, consisting of two insulating layers. Copper strands, stranded, twisted along the central axis. The wire is flexible, making it great for a variety of connections.

The voltage of connected devices must be up to 380 Volts.

Selected depending on the load:

for a current of 6 A, PVA with a cross section of 0.75 mm is used;
for 10 Amperes - the cross-section is 1 mm;
for currents of 16 A – 1.5 mm.

In addition to the PVS wire, for connection there are multi-core cables ShVVP, PUGNP, PRS, KG. They are used less frequently for home wiring than PVS.

What is the best way to reliably connect two cables together?

Methods of connecting cables that require equipment and skills in the field of electrical engineering:

soldering;
welding;
crimping with sleeves.

Simple connection methods that do not require tools or knowledge:

connection using terminal blocks;
spring clamps;
PPE caps;
bolted connection.

The choice of connection method depends on the characteristics of the wires. It is necessary to take into account the type and number of wiring, operating conditions.

With soldering

Soldering is a common method of connecting cables. To work you need a soldering iron, rosin, solder and sandpaper. How to connect wires by soldering:

stripping of insulation;
cleaning from oxides using sandpaper;
the conductors need to be tinned - rosin is placed on the wire, it is heated with a soldering iron until the wire is covered with rosin;
the conductors are assembled together, bubbling rosin must be applied to them and heated until the solder spreads;
The soldering area is cooled.

The complexity of the process lies in the availability of professional skills. Do not overheat the solder area or twist it when heating, otherwise the insulation may melt. It is important to ensure high-quality and reliable contact of the wires. Soldering is used in low-current electrical applications.

No soldering

Solderless connections are made using special connecting elements. It is also possible to connect the wires by twisting. Twisting is the simplest method that does not require equipment, but this method is also the most unreliable.

It is prohibited to use only a twisted connection according to the rules of the PUE.

Copper

Copper wire can be connected using terminal blocks, Wago clamps (necessarily using special paste), using a bolt, or soldering.

Aluminum

Aluminum wires can also be connected using any method, but with some special features. When connecting, the metal must be manually stripped of insulation.

Copper and aluminum wires cannot be connected directly. The connection point becomes very hot and over time the contact weakens. Therefore, it is better to use terminal blocks, wago, bolt connection or special branch clamps.

Is it possible to connect cables by twisting?

According to the rules of the PUE, twisting is prohibited, as it does not provide reliable contact. It can only be used in conjunction with another connection method. It is also unacceptable to use twisting to join two different metals.

Stranded and single-core

When connecting multi-core wires, the following rules should be followed:

strip the insulation by 4 cm;
unwind the conductors by 2 cm;
connect to the junction of untwisted conductors;
twist the wires only with your fingers;
You can tighten the twist using pliers;
bare ones are insulated with special tape or heat-shrink tubing.

Twisting solid wires is much easier. They need to be stripped of insulation, twisted by hand along the entire length, then clamped with pliers and insulated.

Twisting methods

You can do twisting in different ways. It can be made by branch, parallel or series connection. Also, to improve the reliability of contact, caps and clamps are additionally used.

Correct twisting of electrical wiring in a junction box

When twisting, you need to follow the following procedure:

cut off power to a house or apartment;
clear the wiring of 4 cm or more of insulation;
unwind the wires by 2 cm;
connect untwisted wires to the junction;
twist the veins with your fingers;
tighten the twist with pliers;
insulate exposed wires.

Both single-core and multi-core cables can be connected.

Twisting of different sections

Do not twist wires with very different diameters. Such contact is not reliable and stable. You can twist wires of adjacent sections - for example, 4 sq. mm and 2.5 sq. mm. When twisting, you need to make sure that both wires wrap around each other. A thin wire should not be wound onto a thick one, otherwise the contact will be unreliable. Then you need to solder or weld the joint.

Twist caps

The caps help to reliably insulate the contact point. The cap is made of fire-resistant material, inside it there is a metal part with threads.

Making twists using caps is quite simple - you need to remove 2 cm of insulation and lightly twist the wires. A cap is put on them and turned several times until the metal wires are inside.

With terminal clamps

The contact clamp consists of a screw, a spring washer, a base, a current-carrying core and a stop that limits the spreading of the aluminum conductor. Making a connection using a contact clamp is simple - just strip the ends of the wires by 12 mm and insert them into the hole in the clamp. Contact clamps are used for both solid and stranded conductors.

How to brew twist

After twisting, the wires need to be soldered. To do this, the wires are tinned and rosin is applied to them before twisting. The heated soldering iron is lowered into the rosin; it needs to be passed along the stripped part of the wiring. After twisting, take tin on a soldering iron and heat the joint until tin begins to flow between the turns. This method takes a lot of time, but it is reliable and of high quality.

Methods for connecting wires or cables to each other

The junction of two conductors must meet the following requirements:

reliability;
mechanical strength.

These conditions can also be met when connecting conductors without soldering.

Crimping

This method requires special equipment. Crimping of wires with sleeves is carried out for both copper and aluminum wires of different diameters. Depending on the cross-section and material, the sleeve is selected.

Crimping algorithm:

stripping of insulation;
stripping wires to bare metal;
the wires need to be twisted and inserted into the sleeve;
the conductors are crimped using special pliers.

Selection of a sleeve causes major difficulties. An incorrectly selected diameter will not ensure reliable contact.

Bolted connection

Bolts, nuts and several washers are used for contact. The connection point turns out to be reliable, but the structure itself takes up a lot of space and is inconvenient to install.

The connection order is as follows:

stripping of insulation;
the stripped part is laid in the form of a loop with a diameter equal to the cross-section of the bolt;
a washer is put on the bolt, then one of the conductors, another washer, a second conductor and a third washer;
the structure is tightened with a nut.

Using a bolt, you can connect several wires. The nut is tightened not only by hand, but also by a wrench.

Terminal blocks

The terminal block is a contact plate in a polymer or carbolite housing. With their help, any user can connect wires. The connection occurs in several stages:

stripping the insulation by 5-7 mm;
removal of oxide film;
installing conductors in sockets opposite each other;
fixation with bolts.

Pros - you can connect cables of different diameters. Disadvantages - you can only connect 2 wires.

Types of terminal blocks for multi-core and single-core cables

There are 5 main types of terminal blocks:

knife and pin;
screw;
clamping and self-clamping;
cap-shaped;
"walnut" type clamps.

The first type is rarely used; they are not designed for high currents and have an open design. Screw terminals provide reliable contact but are not suitable for connecting multi-core cables. Clamp terminal blocks are the most convenient devices to use; their installation does not require special equipment. Cap-type devices are also often used, but unlike clamping devices, caps can be used repeatedly. "Nut" is practically not used.

Terminals in junction box (copper or metal)

Terminals are the most common connection method in a junction box. They are cheap, easy to install, provide reliable contact fixation and can be used to connect copper and aluminum. Flaws:

cheap devices are of low quality;
Only 2 wires can be connected;
Not suitable for stranded wires.

Self-clamping terminal blocks WAGO

There are 2 types of Vago terminal blocks used:

With a flat spring mechanism - they are also called disposable, since reuse is impossible. Inside there is a plate with spring petals. When installing the conductor, the petal is pressed out and the wire is clamped.
With lever mechanism. This is the best connector option. The stripped conductor is inserted into the terminal and the lever is clamped. Re-installation is possible.

With proper use, Vago terminal blocks last 25-30 years.

Using Tips

For connection, 2 types of tips and sleeves are used:

in the first, the connection is made inside the product;
in the second, two electrical wires are terminated with different tips.

The connection inside the sleeve or tip is strong and reliable. There are also special sleeves for connecting copper and aluminum wires.

Soldering of electrical wiring lugs

The tips are connected to the wiring using a press. If it is not there, contact can be ensured by soldering.

The electrical wire and the tip inside are tinned, the stripped cable is inserted inside.

The entire structure on the contact must be wrapped with fiberglass tape and heated with a burner until the tin melts.

Connectors for wires and cables

Connectors are special devices that facilitate the connection of two or more conductors. There are screw and clamping mechanisms.

Screw terminals

Used to connect wires of different materials and different diameters. The exception is multi-core electrical wires, which are crimped with special lugs. Also, screw clamps can damage aluminum wires, so it is better not to use them for such material.

Screw terminals

Allows you to connect aluminum and copper conductors together. They are easy to connect.

Power clamp

In such clamps, the stripped conductor is placed in the hole to the end. There it is automatically fixed by a pressure plate. Clamps can be used to secure copper and aluminum wires.

Clips

To install the wire, the clip clamp is placed in a vertical position, the wires are inserted inside, and then the clamp must be moved to a horizontal position. Plus, you can make adjustments.

Spring clamps

PPE caps are used as spring clips. Thanks to them, you can quickly make contact between two wires of similar diameters. It is important to choose the correct clamp, otherwise the contact will be unreliable.

Spring terminals

Wago spring terminals ensure reliable contact quickly and efficiently. However, over time, the spring may weaken or overheat.

Connection clamps

There are two types - electrical and electrical. The only difference is the current load. The connection takes place inside the device.

Couplings

It is made in the form of a metal tube. Used for conductors with a cross section of 0.25-16 mm. The wire is fixed by force crimping. Not used for single-core wires.

Connection blocks for electrical wiring in case of damage

If electrical wiring with stranded conductors is damaged, clamping blocks must not be used. They additionally put pressure on the conductors, causing the conductors to become deformed and damaged. As a result, the connection heats up, melts and there is a risk of fire.

Only craftsmen with a qualification group are allowed to weld. Persons who have skills in working with a soldering iron are also allowed to solder.

Cables may only be connected in the manner permitted for them. Do not work with damaged wiring. All exposed parts must be insulated.

You can connect the cables in different ways. The choice of connection method is determined by the material, cross-section diameter and other parameters. For electrical equipment to operate correctly, the conductors need to be connected securely. In case of unreliable contact, there is a risk of fire.

Useful video

High-quality power supply and voltage supply, stable and uninterrupted operation of electrical equipment largely depends on the connection of electrical wires. The size of the consumer's load current depends on the cross-section of the wire and the quality of the connection. For example, if two wires of different diameters are connected: 2 and 1.6 mm 2, the load current (I max) will correspond to 10A for a wire with a smaller diameter of 1.6 mm 2. A reliable connection of wires in the junction box guarantees high-quality operation of the electrical circuit in a residential area.

Types of wire connections

Twisting wires

This connection is one of the most commonly used and recognized as erroneous types of electrical wire connections.

Lack of twisting: the appearance of a gap due to temperature differences that appear during a linear increase in the metal of the conductors as a result of the flow of a large load current. As a result, oxidation of the cores occurs, and a weakening of the contact is observed. The same applies to the connection of copper and aluminum wires.

Twisting, according to the latest PUE requirements, is prohibited for installation, but it is recommended for use for low-current lines for a specific connection of copper wires or only aluminum ones.

First of all, it is unacceptable to connect copper and aluminum wires; in this case, the copper conductor must be tinned with solder; if stranded and single-core wires are connected, the stranded conductor must also be tinned.

In the event that it is necessary to connect two single-core wires in the event of a wire break, the conductor is divided into two cores. The cores are cut and cut at a distance from each other, so that the twisting points do not contact each other, 2 - 5 turns are enough, which it is advisable to solder. You can insulate the twist using cambric, or even without insulating individual conductors; in general, it is enough to fasten strips of insulation along the length of the twist. After this, the twist is insulated with insulation or heat shrink, the number of turns of insulation in accordance with the requirements of the PUE is at least 3.

Soldering wires

This type is not recommended for connecting conductors if heating of the connection is possible when a large load current passes; this requirement is enshrined in GOST R 50571.5.52-2011 and PUE. In the event that soldering is still necessary, a special protective cap with a thread is put on the soldering site.

Fig No. 1. Soldering wires.

Conductor threaded connection

Bolt connection allows the connection of wires made of different metals. It is recommended to constantly tighten the screws, due to the weakening of contact that occurs over time due to temperature changes, with an increased current load. To prevent loosening, a groover is used, it selects the gap that appears and contributes to the reliability of the contact connection. A threaded connection using a screw is bulky and takes up a lot of space.

Fig No. 2. Threaded connection for bolt.

Terminal connection

This type of connection is most widely used in household appliances, as well as in car wiring. The connection is reliable, although due to temperature changes as a result of adding a load or frequent separation of the connection, the wire breaks or the terminal burns out. Replacement occurs after crimping using available tools and soldering the junction of the wires with the terminal.

Fig No. 3. Connection using terminals.

Connection using terminal block

In the event that the network uses small load currents, for example, in circuits of relay protection or fluorescent or other energy-saving lighting. There are two common types of terminal blocks

Terminal block using bolt clamp.
Wago flat spring clamp, this clamp is one of the modern but expensive connecting elements. It is designed for current up to 25A, although in Russian conditions it is better to use it for networks with a load of no more than 10A.

Permanent connection of wires

Permanent methods of connecting wires include:

Pressure test.
Rivet.
Welding.
Bandaging.
Squeeze.
Piercing.

Crimping

The connection is made through the use of a copper or aluminum sleeve, which is placed on the connected cores, which are subsequently pressed with press jaws. For crimping, you can also use (depending on the diameter of the wire) ordinary pliers, or a hammer with a chisel, although pliers are still preferable due to their greater reliability. Crimping can also be performed using a protective cap with a thread; it, at the same time, serves as an insulating element.

In the case of using large cross-section conductors, special hydraulic press jaws are used using a punch and a matrix.

Riveted connection of wires

The connection is made using a rivet and spring (engraver) and flat washers. The Grover separates the conductors made of aluminum and copper, it also does not allow the contact to loosen, a flat washer is put on the outside, conductor rings and separating washers are put on a steel rod, which is inserted into the rivet gun.

Welding wires

The welding connection is carried out in two ways using thermite and arc welding. In the case of arc welding, an inverter machine is used. Welding is performed using a consumable electrode, for example, ANO.

Thermite welding uses thermite, a mixture of aluminum, magnesium, calcium and titanium powders. Often used for working at height when connecting aluminum wires of high-voltage power lines, it is reliable, convenient and quick to connect, no need to use connecting bolt dies. Very convenient in low temperatures and adverse weather conditions.

Banding of conductors

It is performed when connecting both conductors of the same name and for connecting conductors of different names, as well as single-core and stranded conductors. The cores with the insulation removed are folded together, then soft galvanized wire is wound on top of them, covering the area next to the connection, which conducts electric current.

Connecting wires by compression and piercing

This type of connection is used to create a branch from the main overhead or cable power line without interrupting the voltage. If just a few years ago, to connect consumers it was necessary to disconnect the power line and perform twisting, now for a 0.4 kV power network, it is enough to use a special device (compression), the most popular is the so-called “nut”. To compress, you need to strip the insulation, which is life-threatening and for which it is advisable to disconnect the network.

The connection is made by piercing, is leak-tight, and does not require disconnecting or stripping the insulation. Clamping plates have teeth in their design that pierce the insulation and provide a reliable connection. The tightening is adjusted with a hexagon. The connection is permanent and disposable, recommended for SIP wires.

Any man strives to ensure that the electricity supply in his own home or apartment is of high quality, uninterrupted and reliable. Therefore, when carrying out electrical installation work during construction or repairs, it is necessary to correctly connect electrical wires. But in everyday life you still have to face problems when the lamp wire broke, the socket stopped working. Of course, if you have basic knowledge of electrical engineering and the ability to carry out electrical installation work, it is easy to fix all these faults yourself.

The connection of conductors made of different metals must be made taking into account all the properties of the material from which they are made. Currently, copper, aluminum and steel are used to transmit electrical energy. Each of these metals has different densities, conductivities, and resistances that are taken into account when making good electrical contact. It is also necessary to take into account the magnitude of the electrochemical potential that arises when current is applied to the metal.

Therefore, if aluminum and copper conductors are connected incorrectly, problems may occur. serious problems problems that many specialists who repair wiring in apartments encounter. Previously used in homes copper wires, which were much superior to aluminum ones in terms of electrical performance. And currently use of copper conductors faded into the background.

Aluminum, having a high level of oxidation, forms a specific film when combined, which has a fairly high electrical resistance. This property manifests itself especially in humid environments. The same film is formed on copper, only its resistance is much lower. Therefore, due to this difference in resistance, direct connection of these metals results in difficult electrical conductivity. A oxidation processes lead to sparking, heating and fire of wires.

Methods for safe contact

To create reliable contact between electrical wires, there are several methods, both using special equipment and using improvised means.

Types of wire connections:

Twisting (twisting) is the most common method, the use of which is desirable for temporary connections.
Welding is the most reliable method that ensures excellent contact of conductors. Requires welding equipment and certain skills to carry out the work.
Soldering - has excellent connection performance, but requires compliance with the temperature regime (not higher than 65℃).
Terminal blocks are a fairly simple and reliable connection.
Connecting wires using clamps - subject to operating conditions - allows you to get excellent contact. Installs very quickly.
Crimping with sleeves requires special pliers and knowledge of installation technology, but the method is very reliable.
Bolted connection - used in difficult situations, easy to perform and does not require special devices.

When choosing the type of connection, it is necessary to take into account: the material of the conductive part; wire section; number of conductors; type of insulation; terms of Use. Most often, the selection of the type of connection is carried out at the work site.

This technological operation is common to all methods of connecting conductors. Before combining the wires into a common electrical unit, it is necessary to strip them of the insulation layer.

The easiest way to do this work is with a mechanic's knife, but in this case there is a possibility of damage to the conductive core. To avoid this, you need to:

Place the wire on the table surface.
Press it with the index finger of your left hand.
Holding the knife in your right hand, cut the insulation. In this case, it is necessary to direct the blade at an angle to the cut so as not to damage the core. Otherwise, the conductor may break.
Using the finger of your left hand, twist the conductor one turn to cut the insulation.
Remove the cut piece of the insulating sheath.

Experienced electricians have in their arsenal a multifunctional tool - a stripper, which is designed for cutting cables and removing insulation. This device does not damage the core when removing insulation from a conductor of any cross-section, since it has a special calibrated recess for the required wire diameter.

The length of insulation stripping is selected in accordance with the method of connecting the conductors.

The simplest and most well-known method of connecting electrical wires is twisting them (twisting). Experienced electricians often call it the old-fashioned method.

Previously, this type of connection was used everywhere, but with increasing load in the electrical network in a modern apartment, twisting has become prohibited. However, this connection method must be studied first, since it is the main step in soldering and welding wires.

The main advantage of twisting is the absence of any material costs, since you only need pliers and a knife to remove the insulation. And of course, the advantage of twisting is the ease of its execution. Anyone who has held pliers in their hands can do this job without any problems.

Over time, the twist weakens, which is its main disadvantage. This process is connected with the fact that in any veins there is residual elastic deformation. Therefore, at the point of twisting, the contact resistance increases, which leads to weakening of the contact and heating of the conductor. It would be good if this defect is discovered in time and the junction can be redone, but a fire may occur.

But if for some reason you do not have the opportunity to use more reliable methods, then you definitely need to familiarize yourself with how to properly connect the wires to each other using the twisting method. To do this, you first need to strip the cores of 70-80 mm of insulation. Then, holding both conductors where the insulation ends, use pliers to grab the ends of the wires and rotate them clockwise. Main the condition for reliable twisting is the simultaneous rotation of the conductors, and not alternately winding them on each other.

If the diameter of the wires is small, then twisting can be done entirely by hand. With your left hand you need to hold the conductors along the cut of the insulation, and with your right hand you need to rotate the conductors by the bend (10-15 mm) clockwise. For tighter contact at the end of the rotation, you can use pliers.

The next step is to insulate the junction of the wires. Insulating tape is used for this. To ensure reliability and protect the contact from moisture, you need to wind the tape in several layers, while stepping 2-3 cm onto the wire insulation. A very good option for insulation is the use of thermal tubes; the main thing is not to forget to put it on one of the cores.

Professional electricians advise not to stop at the stage of twisting the wires, but to strengthen the joint by soldering or welding.

How to connect wires by soldering

The type of connection in which electrical wires are joined using molten solder is called soldering. This method is best applicable to wires with copper conductors, but the use of special fluxes allows you to obtain high-quality joints of other metals.

Advantages of using soldering:

In terms of reliability, this type of connecting wires is second only to welding;
allows you to connect both single-core and stranded wires, as well as wires with different sections;
no maintenance of the contact point is required for the entire period of operation;
low cost of work (flux and solder are inexpensive).

The disadvantage of soldering is considered to be rather high labor intensity. The surfaces to be soldered must be previously cleaned of oxides and tinned before twisting the wires.

An electrician must have certain qualifications and be able to use a soldering iron, because during the work it is necessary to strictly observe the temperature regime. A weakly heated or overheated contact point loses its reliability and strength.

The technological process for performing soldering looks like this:

The insulation is removed from the conductors by 40-50 mm.
Areas of exposed veins are well cleaned with sandpaper.
Tinning of wires is carried out. To do this, a heated soldering iron is dipped in rosin and the tip is passed several times over the cleaned surfaces.
The wires are twisted.
Place solder on the soldering iron tip and heat the twist. In this case, molten tin should fill all the gaps between the turns.
After cooling, the soldering is wiped with alcohol and insulated.

To create the most reliable connection of the conductors after twisting, they are additionally secured by welding. The technology for making such a contact is very similar to soldering, only here a welding machine is used instead of a soldering iron.

In terms of quality and reliability, the welding method fully meets all regulatory requirements for creating electrical contact.

When creating a connection by welding, the conductors are twisted and their tip is welded. The resulting metal ball provides a very reliable connection of the wires. At the same time, reliability is due not only to the creation of high electrical characteristics, but also mechanical ones.

The main disadvantage of this type of wire connection is the presence of a welding machine and devices for such work. In addition, it is necessary to strictly adhere to the rules of working at height and fire safety.

Sequence of welding wires:

We remove 60-70 mm of insulation from the conductors.
We clean the cores mechanically (sandpaper).
We twist the wires, and its length must be at least 50 mm.
We fix the welding grounding contact on top of the twist.
Lightly touch the bottom of the twist with the electrode. Wire welding occurs very quickly.
After the contact ball has cooled, we insulate it.

As a result of such actions, an almost solid conductor is obtained, and the contact node will have the lowest transition resistance.

For such a connection of conductors, special copper or aluminum sleeves are required, which are selected in accordance with the size of the bundle diameter. It is advisable to use the same material for the sleeves as that of the conductor.

The wires are stripped to the length of the sleeve, rolled up and placed in a tube. Then, using special pliers, the connection is pressed and insulated.

There are tube sleeves for extending conductors, that is, for attaching them longitudinally. The wires are inserted into such sleeves from different sides of the tube, then crimped individually.

Bolt method

This connection is used in electrical circuits with high voltage. Its use is suitable for switching almost any conductor.

put the washer on the bolt;
first conductor;
next washer;
second conductor;
puck again;
screw.

Then the assembled assembly is tightened by hand, and then pressed with a wrench or pliers.

Modern industry has mastered the production of special wire connectors, which have made work much easier and have sped up switching work:

Caps with built-in crimp spring. The stripped wires are inserted into such a cap and turned clockwise. With this action, the wires are securely compressed inside.
Terminal blocks, which have tubular brass sleeves inside. Bare wires are inserted into these sleeves and clamped with screws.
Self-clamping terminals The stripped wire is automatically fixed with a special plate.
Lever terminal blocks are considered reusable devices. Fixation of the conductor is ensured by raising and lowering the lever.

Remember that the connection of wires must always be made on de-energized electrical networks. Without knowledge of electrical engineering, it is better to entrust work involving dangerous voltage to specialists.

Connecting the wires in the junction box requires special care. Not only the reliable operation of electrical appliances, but also the safety of the premises depends on how correctly the work is done.

Wires from the electrical panel are distributed to individual rooms of the apartment or house. Moreover, each room usually has not one, but several connection points (sockets and switches). To standardize the connection of conductors and concentrate them in one place, distribution boxes are used (their other names are “junction boxes” or “branch boxes”). The boxes contain cables from all consuming devices.

The wires in the box are not laid chaotically, but in accordance with clear rules prescribed in the Electrical Installation Rules (PUE). According to the requirements of the PUE, all connections of wires in the box, as well as branches, are made only inside the junction box. The conductors are directed along the top of the wall, but no closer than 15 centimeters from the ceiling. When the cable reaches the branch section, it descends strictly vertically. At the branch site there is a distribution box. The connections in it are made according to the existing diagram.

Junction boxes are classified by installation type. There are internal and external junction boxes. There is a niche in the wall for hidden-mounted boxes. Only the cover remains on the surface, which is installed flush with the finishing material. It is allowed to cover the lid with decorative panels. If the thickness of the walls or other circumstances do not allow the installation of an internal junction box, it is mounted directly on the wall.

The distribution box can be rectangular or round. The number of pins is usually four, but in some cases there are additional pins. Each outlet is equipped with a fitting or thread for securing a corrugated hose. The presence of such a hose or plastic pipe greatly simplifies the process of laying and replacing wires. To replace the wires, it will be enough to disconnect the hose or pipe from the junction box and the consumer, and then pull it out. After replacing the conductors, the hose is returned to its place. If the wires are located in a groove, you will need to break up the layer of plaster, which is much more labor-intensive.

The use of junction boxes leads to the following positive results:

The maintainability of the electricity supply system increases. Since all connections are easily accessible, it is much easier to find the damaged area.
The overwhelming majority of faults are found at joints. Since all connections are concentrated in one place, it is easier to carry out preventive inspections.
Thanks to junction boxes, the degree of fire safety increases.
The use of junction boxes allows you to save money and reduce labor costs when laying cables.

Methods for connecting conductors

There are many options for connecting wires in a junction box. The choice of a specific method depends on the following factors:

the material from which the cores are made (steel, copper, aluminum);
environmental conditions (outdoor/indoor, working in land or water, etc.);
number of wires;
coincidence or mismatch of the cross-section of the cores.

Taking into account these parameters, the most suitable technique is selected.

The following methods are used to connect wires in the junction box:

terminal blocks;
Wago spring terminals;
self-insulating clips (PPE, or plastic caps);
twisting;
crimping with sleeves;
soldering;
"nuts";
bolted connections.

Below we will consider the features of each of the listed methods.

Terminal blocks

Terminals are devices made of plastic, the inside of which contains a brass bushing. There are screws on both sides of the bushing.

To connect the wires to each other, you need to insert a conductor on each side of the terminal block and secure them tightly with screws. This joining method is most common in distribution boxes, as well as when installing lighting fixtures, sockets and switches.

Note! The inlet holes of the terminal blocks differ in diameter depending on the cross-section of the conductors intended for them.

Advantages of the method:

low cost of terminal blocks;
simplicity and convenience of installation work;
reliability of conductor fixation;
the ability to connect poorly compatible materials such as copper and aluminum.

Disadvantages of the method:

The pads offered for sale are often of low quality, which is discovered during mating and forces the products to be rejected.
Only two wires can be connected.
Terminal blocks are not suitable for aluminum or stranded conductor because aluminum is brittle and the stranded conductor strands are too thin.
Although the method is reliable, a better connection can be obtained, for example, by soldering.

Wago terminals

Wago spring terminal blocks are one of the most popular devices used in connecting wires.

Unlike standard terminal blocks, in Wago docking is carried out not with screws, but with the help of a special mechanism. The device is equipped with a lever that allows you to secure the conductor while maintaining its integrity. Before using Wago, you need to remove the insulating layer. Next, the cores are directed into the block hole.

Note! There are both disposable and reusable pads on the market. Disposable fasteners mean that they can only be used once, and if the wire is replaced, the pads become unusable. Reusable terminals are more expensive, but can be easily removed and then reused for their intended purpose.

Advantages of Wago spring pads:

You can connect both conductors from the same metal and dissimilar materials.
It is possible to connect multiple cores (three or more).
When fixing multi-core conductors, thin wires do not break.
The pads are small in size.
Working with pads does not take up extra time, the process is not labor-intensive.
The fastening is of high quality.
The block has a hole for an indicator screwdriver to monitor the functioning of the electrical network.

Wago has one drawback - the high cost of products.

Self-insulating clips (PPE)

A self-insulating clip (or connecting insulating clip) is a plastic cap, inside of which there is a special spring for fixing the wire.

The advantages of PPE include the following characteristics:

Low cost.
The products are made from non-flammable plastic, therefore, there is no danger of spontaneous combustion of electrical wiring at the junction point.
Easy installation.
A wide variety of color shades, which allows you to color-code phase, neutral and ground.

The disadvantages of PPE include:

low fastening and insulating qualities;
impossibility of using for connecting aluminum and copper conductors.

Crimping with sleeves

Connecting wires in a junction box using sleeves is considered a method that ensures high quality connections. The essence of the technique is to place the stripped cores in a special tube (sleeve), which is then subjected to crimping by crimping. Next, the sleeve is treated with insulating material, for which heat-shrinkable tubing or regular insulating tape is used. Wires can be inserted from both ends of the tube, or only from one end. In the first case, the joint will be located in the middle part of the sleeve, but in the second case it is necessary that the total cross-section of the cores is no larger than the cross-section of the sleeve.

Advantages of crimping:

The connection is of high quality and reliable insulation.
Affordable prices for sleeves.

Disadvantages of crimping:

The sleeve cannot be replaced once removed - it is a one-time use attachment.
The connection will require the use of specialized tools (crimping pliers, pipe cutter).
Crimping of aluminum and copper wires is possible only with the help of a specially designed sleeve.
The work is labor intensive.

Soldering

Connection using soldering is considered the highest quality of all possible. Before docking, you need to thoroughly clean the conductors. Next, the bare ends are treated with molten solder, after which the wires are immersed in the bath. When the conductors have cooled, insulating material (cambric or electrical tape) is applied to them.

Note! The cooling process should not take place in cold weather, since as a result of too rapid cooling, the material will become covered with microcracks, which will greatly deteriorate the quality of fixation of the conductors.

As already mentioned, the main advantage of soldering is the unsurpassed quality of the connection.

Disadvantages of the technique:

A specialized tool is required, as well as skills to handle it.
The work requires significant labor costs.
The connection is permanent, that is, disposable.
There are restrictions on the use of soldering, which are detailed in the PUE.
Over time, soldering resistance increases, which is reflected in the form of voltage loss and electrical conductivity.

Thus, despite the reliability of the connection, specialists rarely turn to soldering.

Welding is sometimes used instead of soldering. The essence of this method is the same as in the case of soldering. The only difference is the need for different skills, namely the ability to work with a welding machine.

Twist

Connecting wires in a junction box using the most primitive method - twisting - is not used so often due to significant limitations: poor quality of fastening and the impossibility of joining aluminum and copper conductors. However, twisting is still sometimes found, since it is attractive due to its ease of implementation, as well as the lack of financial costs. Most often, twisting is used when laying temporary electrical wiring. It is recommended to use cambrics as an insulating material.

Note! Twisting is unacceptable in rooms with high humidity, as well as in wooden buildings.

Walnut clamp

The “nut” is a cable clamp with two plates and four bolts in the corners. Before connecting, the insulation is removed from the wires. Next, the conductors are fixed in the plate and covered with a carbolite shell.

Benefits of "nut":

Low costs.
Installing the “nut” is not very difficult.
It is possible to connect dissimilar materials (aluminum and copper).
High quality insulation.

Disadvantages of this method:

The fasteners weaken over time and need to be tightened regularly.
The “nut” is not the best method of mounting in a distribution box due to the excessive dimensions of the connection.

Bolted connection

Bolting is a very simple but effective way of connecting conductors to each other. To complete the job, you only need a bolt, three washers and a nut. The diagram for connecting the wires in the junction box using a bolt is shown in the picture below.

A washer is threaded onto the bolt thread. Next, the core is wound (the insulation must first be removed). After this, the thread is laid with a second washer and another core. At the end, a third washer is placed, which is pressed with a nut. The connection must be covered with insulating material.

The bolted connection has the following advantages:

low cost;
ease of implementation;
the ability to connect products made of copper and aluminum.

Disadvantages of connecting conductors with bolts:

Insufficient quality of fixation.
You will need a lot of insulating material.
The bolt is too large and may not fit into the junction box.

Solving other problems

The connection of stranded wires has a number of features.

Connecting many wires

Options for connecting two contacts were discussed above. If we are talking about connecting multiple contacts, it is recommended to choose among the following options (in order of priority - from the best method to the worst):

The rules for docking using the indicated methods, as well as their advantages and disadvantages, are discussed above.

Docking of cores with different sections

To combine cores of unequal cross-sections in a junction box, you will need Wago terminal blocks, although you can get by with standard terminal blocks - the latter option will be cheaper. In this case, it is necessary to secure the cores tightly using a screw or lever.

Note! If the wires not only have different sections, but are also made of different metals, you will need special pads, inside of which there is a special composition to prevent oxidative processes. Similar pads are available in the Wago range.

Cores with different sections can also be secured by soldering.

Joining of stranded and single-core conductors

The combination of conductors with one and multiple cores is carried out in the same way as all others. In this regard, you can choose any of the above methods, but the highest priority is soldering or terminals (preferably Wago).

Procedure for carrying out work in land and water

It is not so rare that there is a need to lay electrical wiring underground or underwater. Let us briefly dwell on the features of performing electrical installation work under these conditions.

Wires can be laid in water, for example, when installing a submersible pump. In this case, soldering of the wire ends is necessary. Next, the connection is treated with insulating material (hot glue), and heat shrink is put on top. If the technology is followed, the joint will be very reliable and safe. However, if you are careless, it will end in a short circuit.

Wiring in the ground is protected in the same way as described above, however, to obtain a secure connection, a more advanced technique can be used. The ends of the cable should be pressed with a terminal block, and the sealed junction box should be filled with silicone. It is recommended to place the underground pipeline in a durable box or pipe to prevent acts of pestilence by rodents. Damaged cable ends are best joined using couplings.

Basic wiring diagrams

Above we talked in some detail about how to connect the wires in the junction box. However, the work is not limited to connecting wires in the junction box. You also need to connect the wires to sockets and switches.

Connecting sockets

A group of sockets is usually separated into an independent line. There are three wires in the box, each of which has a color specific to its purpose. Brown is usually live, blue is neutral, and green/yellow is ground. In some cases other colors are used. For example, phase is red, zero is blue, ground is green.

Before laying, the wires are laid out to their full length and trimmed so that they are the same length. It is necessary to have 10-12 centimeters of reserve - just in case. The connection of conductors is carried out using one of the methods described above.

If only a pair of wires is involved (where grounding is not used), then we are talking about neutral and phase. If the conductors are the same color, you first need to find the phase using a multimeter. For convenience, it is better to mark the phase wire with electrical tape or a marker.

Connecting a one-button switch

In the case of a switch, there are also three groups, but the connection is made a little differently. There are three inputs: from the junction box or electrical panel, from the lighting fixture, from the switch. The phase wire is connected to the switch button. From the output of the switch the wire is directed to the lamp. In this case, the lighting device will only work when the switch contacts are closed.

Connecting a two-button switch

In two-key switches, the circuit is somewhat more complex. A three-wire cable must go to the switch serving two groups of lighting fixtures (if grounding is not used). One conductor is assigned to the common contact of the switch, the remaining two are directed to the output of the buttons. The phase is combined with the common contact of the switch. The neutral wires from the input and two groups of lighting fixtures are connected. Phase wires from lighting fixtures and two conductors from the switch are combined in pairs: one from the switch to the phase of one of the lamps, the second from the switch to the other lamp.

When installing an additional outlet, connecting a new chandelier, or troubleshooting a fault in the electrical wiring, you will have to deal with electrical work. Without practical experience, it is difficult to ensure reliable contact between conductors made of different materials, having different cross-sections or completely different numbers of cores.

The article we have proposed describes in detail all the methods of connecting electrical wires that are used in the construction of electrical wiring. We analyzed the technical and technological features of each option. With our advice, you can successfully repair or upgrade your electrical network.

Any electrical installation work should be carried out competently. It is important to remember that the safety and life of all people and animals living in a house, apartment or country house depends on the correctness of their implementation. A mistake is unacceptable - at best there will be no good contact. And these are non-working electrical points.

In the worst case scenario, a visiting family member, friend or acquaintance could be electrocuted by an improperly insulated connection. Or the wiring will catch fire, which could lead to a fire.

For high-quality and correct execution of electrical wire connections, you need:

knowledge of the basic types and principles of connections;
availability of special tools for electrical installation work;
availability of all consumables that will be useful when performing a specific type of connection;
preliminary training on individual sections of wires.

When everything you need is available, you should carefully prepare your future place of work. To do this, you need to de-energize all the wires that you have to deal with. This is a very important step that cannot be ignored!

Without knowledge of electrical installation, it is better to entrust the replacement of electrical wiring to a professional electrician

To avoid getting an electric shock, it is better to make sure once again that the apartment or house is actually de-energized. In this case, it is convenient to use an indicator screwdriver - this is an inexpensive tool that can even be purchased in an online store.

It’s convenient when, in addition to the desire to do everything yourself, you also have the necessary tool - with it, performing electrical work is much easier and faster

In a situation where there are serious concerns about the advisability of carrying out electrical work yourself, it is better to contact an electrician. Moreover, you should invite only an experienced craftsman who has not only experience in carrying out such work, but also special education.

Electrician services will be especially relevant if you are planning to build a house. You can’t save on this - in the end you can pay double or triple the price, or even pay with your property.

Overview of popular connection types

The main types of connections used in household needs have about 10 options. Among them, there are both simple ones that can be performed without many years of experience, and more complex methods that require not only experience, but also special tools and skills to work with them.

Complex connection options

The connection of two or more wires is carried out in order to obtain high-quality contact. It is he who will ensure the operability of all electrical points in a particular house or apartment.

You can establish reliable contact between conductors on your own or invite a specialist. It all depends on the type of connection chosen, the availability of tools and skills in carrying out such work.

Complex types of connections include:

soldering;
welding;
crimping.

These options will be quite difficult for a beginner to deal with. The fact is that to solder an assembly of two or more conductors you will need a special tool, the skills to work with it are one awkward movement and instead of reliable contact you can get the opposite result.

For soldering, you need to take solder from a tin-lead alloy, rosin and a brush for applying it, a soldering iron and sandpaper for stripping the core

The essence of this method is to remove the insulation from the conductors of the connected conductors and sand them to a shine. Then you need to apply rosin to each vein with a brush and heat it thoroughly with a soldering iron - the stripped metal should be covered on all sides with an even layer of rosin.

When all the conductor strands are prepared, all that remains is to twist them well and heat the solder with a soldering iron, and also heat the resulting twist until the rosin boils. Now you need to apply solder with a soldering iron to the heated assembly of conductors and ensure that it flows evenly between the individual wires.

When using welding, soldering and pressing pliers, a strong and incredibly reliable connection is obtained. In such nodes, contact will not be lost even after 30 years

Once it has been possible to obtain a complete distribution of liquid solder over the entire surface to be soldered, soldering can be completed. Now all that remains is to wait until the resulting assembly cools down naturally.

Welding is an even more complex type of connection. To complete it you will need:

welding machine;
carbon electrode;
flux, which will protect the melt from exposure to oxygen;
protective mask for the face and special heat-resistant gloves for the hands.

And the most important thing when working with welding is the ability to use the device. In the hands of an amateur, instead of a reliable contact that can last 30-50 years, a melted conductor and damaged insulation will come out from under the welding machine.

Before starting welding, you need to twist it, just like before soldering, until it shines. The essence of welding is to obtain a monolithic metal joint. To do this, you need to pour flux into the recess of the carbon electrode, turn on the welding machine and lower the end of the twist into the same recess.

The ball at the ends of the cores of the connected conductors will ensure reliable contact. Moreover, this method is excellent for multi-core wires

As a result of welding, the ends will melt and a metal ball will form on them. You need to wait for it to cool, clean it of flux and varnish it.

For crimping, you will also need special equipment - press pliers, also called a crimper, and a metal sleeve made of copper, aluminum, a combined alloy or insulation.

To obtain high-quality contact using this method, you need to prepare the conductor cores in the same way as before soldering. For stripping, it is better to use side cutters as a last resort. Then take the sleeve and place the prepared conductors of one conductor into it on one side, and the second conductor on the other.

The distance to which you need to strip the insulation from the conductor cores depends on the chosen connection method

Now you have to use press pliers to compress the connection on both sides. It is important that the sleeve or other type has a diameter suitable for the cross-section of the wires being connected - the cores must fit freely inside.

After compression with a crimper, you should check the quality of the crimping - you need to tug one and the other wire. If they are tightly clamped and do not fall out of the sleeve, then the contact is successful.

All connections obtained as a result of soldering, welding or crimping must be insulated. To do this, use electrical tape or heat shrink tubing.

The second option is more convenient and is now used by both professional electricians and home craftsmen. Moreover, when creating a contact using crimping, the heat-shrinkable tube must be put on before inserting the cores into the sleeve.

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Select a liner with the correct material and inner diameter

Select a heat shrink tube of the required diameter. It is important to put it on the wire before crimping with a crimper.

Using press pliers, press the connection on one and the other side, trying to create reliable contact

Place a heat-shrink tube on top of the resulting assembly and heat it with a hair dryer or lighter so that it tightly grips and insulates the contact

Step 1: Select the sleeve of the required diameter

Step 2: Select heat shrink tubing

Step 3: Crimp the connection using a press pliers.

Step 4: Place the tube on top

Easy ways to create contacts

In addition to labor-intensive and complex options for creating a contact, which require skill and special tools, there are simpler ones that can be easily mastered with your own hands. Such methods are acceptable for connecting two or more wires with different cross-sections or the same. And the material of the cores can be different - copper, aluminum or steel.

Simple methods most often used at home include the following compounds:

twist;
bolted;
screw;
self-clamping.

There are two options for twisting, which can be done at home. The first is to simply twist the wires, stripped to a shine, and wrap electrical tape or heat-shrink tubing on top. The second option is to screw a PPE cap over the twist.

Using insulating tape is extremely inconvenient, especially in hard-to-reach places. It is better to buy heat shrink tubing of the required diameter. Moreover, its price is quite affordable

The first option is a relic of the past. Such connections are unreliable, they can fall apart and contact is lost. In the second case, reliability is countered by the high price for one cap. It is not worth buying cheaper products - they cannot withstand the inclusion of a powerful heater in the network or other electrical appliances.

For a bolted connection, you need to prepare a bolt, washers one more than the number of conductors to be connected, and a nut. When creating a contact, the conductors are prepared in the same way as before welding or soldering. One condition is that the length of the stripped core should be enough to wrap around the bolt 3-4 times.

First, a washer is put on, then the conductor core is wound, then the washer again, again the core of the second conductor, the washer again, etc. When the cores of all conductors are wound, the last washer is put on and the whole thing is secured with a nut. The key must be used to tighten the connection well to ensure good contact. The resulting node must be isolated.

Another simple and inexpensive method is screw connections. They are made using terminal blocks. Moreover, the length of the area that needs to be cleaned from insulation to a shine depends on the model of the device and the cross-section of the conductor.

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The PPE cap is easy to put on, as if screwed on top of a twist of wire. It is important to buy an original analogue, not to be tempted by a cheap fake

A bolted connection allows you to create contact between conductors made of different materials, and the diameter does not make a fundamental difference here

Screw terminal blocks are inexpensive and can be cut into the required number of cells, but they are not suitable for stranded conductors

The PPE cap is easy to put on

Bolted connection

Screw terminal blocks are inexpensive

Terminal block with clamping plate

The simplest option is self-clamping devices or. They create a reliable contact and are easy to use. Another advantage is the possibility of reusable use. Even a person very far from electrical installation can remove and reinstall WAGO.

Which option should you prefer?

To choose the right method of implementation, you should take into account the characteristics of your situation, assess the volume of future work and your skills. If we are talking about replacing a chandelier, then there is no point in learning the intricacies of welding and buying a welding machine. Here you can spend money on buying original German WAGO terminal blocks.

When there is a full-scale renovation of an apartment or house with replacement of wiring, it is more advisable to use the welding method. If you don’t have the skills to work with this equipment, then you can practice doing high-quality crimping and create all the contacts yourself.

Junction boxes often use screw or. But there is one caveat - they should be tightened periodically. Therefore, it is necessary to arrange the boxes in such a way as to ensure easy access to them for inspection.

One-piece, disposable clamps. If you need to break the connection and create a new one, you will have to cut off the old contact node

Using regular twisting and, as before, wrapping electrical tape on top is extremely dangerous. Moreover, this option is prohibited by electrical installation rules.

Technical nuances of the main types of connections

Each of the popular types of contact creation has its own characteristics. Thus, only single-core conductors of the same material can be connected by twisting.

If you need to create a contact with multi-core wires, then you need to use special tips - they compress the bundle of small wires. After installing the lug, the conductor can be connected to the terminal clamp without a clamping strip.

To make a reliable connection, stranded wires must be compressed with a special tip