Connection of copper wires to each other. Ways of connecting electrical wires types for different sections

Junction boxes perform a very important function. It is they who ensure the distribution of electrical wires between consumption points, i.e. switches, lights and sockets.

Decided to install the devices listed above yourself? Then you need to thoroughly understand the features and order of connecting cables, as well as the basic methods of connecting them.

For a better understanding of the process, this event will be considered in several stages: from preparing the necessary materials to connecting electrical appliances using the example of a socket, a two-gang switch and light bulbs. Beforehand, you will learn about the main methods of connecting cables and the features of the connection.

Wire connection methods

There are several methods for connecting electrical wires. You can choose the most convenient and suitable option for your case.

Prices for cables and wires for construction and repair

Cables and wires for construction and repair

The first stage - getting ready for work

First of all, we prepare everything that is required to connect electrical appliances to the box. Set includes:

• cables 3x2.5, VVG;
• cables 2x2.5, AVVG;
• switch for 2 keys;
• fastenings;
• lighting;
• socket;
• round nose pliers;
• roulette;
• wire cutters;
• pliers;
• flat screwdriver;
• hammer.

The second stage - do the markup

At this stage, we mark the installation locations of electrical appliances and the paths for the passage of wires. So we can calculate the required amount of materials for the installation of the system.

The third stage - proceed to installation

First turn off the electricity supply.

We bring the wires to the junction box. As a rule, cables are laid in strobes. To fix the cables, small nails or special plastic clips are used. In the case of performing work in a wooden house, the wires will be supplied through special mounting boxes.

Important note! Wiring must be laid so that the cables do not intersect. In the event that intersections are inevitable, such places must be isolated especially carefully.

The fourth stage - we connect electrical appliances and connect the wires

We start in a junction box pre-built into the wall or fixed on the base (depending on the model) about 10 cm of wire. We remove the common sheath from the cables. Then we remove approximately 0.5 cm of insulation from each core. At this moment, we are guided by the situation - we clean off as much insulation so that the cores can be connected in the chosen way.

The diagram shows an example of connecting electrical wires using terminal blocks.

In this example, the connection is made using a two-wire wire, in which one core is zero, the second is a phase. We connect the socket to zero and. We connect the phase supply wire to the socket and one residential cable of the switch.

In our example, the switch is a two-button switch. Each key is responsible for controlling a separate group of lighting fixtures. The second wire of the switch cable is connected to the first button, the third wire is connected to the second key.

In the junction box, zero wires are connected from the socket and bulb holders. The power cable is connected: zero is marked in blue, phase is in red. Wires are connected to connect each switch button to the lamp sockets.

Fifth stage - check the performance of the system

We turn on the power supply and check the operation of our outlet and. Everything is working properly. We did a great job.

Now you know the order of connecting the wires in the junction box and the connection features of each main electrical appliance. Using the information received, you will be able to independently cope with all the planned activities.

Successful work!

Video - Connecting wires in a junction box

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Contact connections of conductors are a very important element of the electrical circuit, therefore, when performing electrical work, you must always remember that the reliability of any electrical system is largely determined by the quality of the electrical connections.

All contact connections are subject to certain technical requirements. But first of all, these connections must be resistant to mechanical factors, be reliable and safe.

With a small area of ​​contact in the contact zone, a rather significant resistance can occur for the passage of current. The resistance at the point where the current passes from one contact surface to another is called transient contact resistance, which is always greater than the resistance of a solid conductor of the same size and shape. During operation, the properties of the contact connection under the influence of various external and internal factors can deteriorate so much that an increase in its contact resistance can cause overheating of the wires and create an emergency. The transient contact resistance largely depends on the temperature, with an increase in which (as a result of the passage of current) an increase in the contact resistance occurs. Heating of the contact is of particular importance in connection with its influence on the process of oxidation of the contact surfaces. In this case, the oxidation of the contact surface is the more intense, the higher the contact temperature. The appearance of an oxide film, in turn, causes a very strong increase in contact resistance.

A contact connection is an element of an electrical circuit where two or more individual conductors are electrically and mechanically connected. At the point of contact of the conductors, an electrical contact is formed - a conductive connection through which current flows from one part to another.

A simple overlay or slight twisting of the contact surfaces of the connected conductors does not provide good contact, since due to microroughness, the actual contact does not occur over the entire surface of the conductors, but only at a few points, which leads to a significant increase in contact resistance.

At the point of contact between two conductors, there always occurs a contact resistance of an electrical contact, the value of which depends on the physical properties of the materials in contact, their condition, the compression force at the point of contact, temperature, and the actual area of ​​contact.

From the point of view of the reliability of electrical contact, aluminum wire cannot compete with copper wire. After a few seconds of exposure to air, the pre-cleaned aluminum surface is covered with a thin hard and refractory oxide film with high electrical resistance, which leads to increased transient resistance and strong heating of the contact zone, resulting in an even greater increase in electrical resistance. Another feature of aluminum is its low yield strength. A strongly tightened connection of aluminum wires weakens over time, which leads to a decrease in the reliability of the contact. In addition, aluminum has the worst conductivity. That is why the use of aluminum wires in household electrical systems is not only inconvenient, but also dangerous.

Copper oxidizes in air at normal residential temperatures (about 20 °C). The resulting oxide film does not have great strength and is easily destroyed by compression. Particularly intense oxidation of copper begins at temperatures above 70 °C. The oxide film on the copper surface itself has negligible resistance and has little effect on the value of the transient resistance.

The state of the contact surfaces has a decisive influence on the growth of the contact resistance. To obtain a stable and durable contact connection, high-quality cleaning and surface treatment of the connected conductors must be performed. The insulation from the cores is removed to the desired length with a specialized tool or knife. Then the bare parts of the veins are cleaned with an emery cloth and treated with acetone or white spirit. The length of the cut depends on the characteristics of the particular method of connection, branch or termination.

The transient contact resistance decreases to a large extent with an increase in the compression force of the two conductors, since the actual contact area depends on it. Thus, to reduce the transition resistance in the connection of two conductors, it is necessary to ensure their sufficient compression, but without destructive plastic deformations.

There are several ways to make an electrical connection. The highest quality of them will always be the one that provides, under specific conditions, the lowest value of the transient contact resistance for as long as possible.

According to the "Electrical Installation Rules" (clause 2.1.21), the connection, branching and termination of wire and cable cores must be carried out by welding, soldering, crimping or clamping (screw, bolt, etc.) in accordance with applicable instructions. In such connections, it is always possible to achieve a consistently low contact resistance. In this case, it is necessary to connect the wires in compliance with the technology and using appropriate materials and tools.

Connection of wires in the junction box is an important and responsible operation. It can be performed in various ways: using terminal blocks, by soldering and welding, by crimping, and often by ordinary twisting. All of these methods have certain advantages and disadvantages. It is necessary to choose a connection method before starting installation, as this also involves the selection of appropriate materials, tools and equipment.

When connecting wires, the same color of neutral, phase and ground wires should be observed. Usually the phase wire is brown or red, the zero worker is blue, the protective earth wire is yellow-green.

Very often, electricians have to connect a wire to an existing line. In other words, you need to create a branch wire. Such connections are made using special branch clamps, terminal blocks and piercing clamps.

With a direct connection of copper and aluminum wires, copper and aluminum form a galvanic pair, and an electrochemical process occurs at the point of contact, as a result of which the aluminum is destroyed. Therefore, to connect copper and aluminum wires, special terminal or bolted connections must be used.

Wires connected to various devices often need special lugs that help ensure reliable contact and reduce contact resistance. Such lugs can be attached to the wire by soldering or crimping.

Tips are of various types. For example, for copper stranded conductors, lugs are produced from a seamless copper pipe, flattened and drilled for a bolt on one side.

The connection of conductors by welding gives a monolithic and reliable contact, so it is widely used in electrical work

Welding is performed at the ends of previously stripped and twisted conductors with a carbon electrode using welding machines with a power of about 500 W (for a twist section of up to 25 mm2). The current on the welding machine is set from 60 to 120 A, depending on the cross section and the number of wires to be welded.

Due to the relatively low currents and low (compared to steel) melting temperature, the process occurs without a large blinding arc, without deep heating and splashing of the metal, which makes it possible to use goggles instead of a mask. In this case, other security measures can be simplified. At the end of welding and the wire cooling, the bare end is insulated with electrical tape or heat shrink tubing. After a little training with the help of welding, you can quickly and efficiently connect electrical wires and cables in the power supply system.

When welding, the electrode is brought to the wire to be welded until it touches, then it is retracted to a short distance (0.5-1 mm). The resulting welding arc melts the twisted wires until a characteristic ball is formed. Touching the electrode should be short-term to create the desired melting zone without damaging the wire insulation. It is impossible to make a long arc length, since the welding site turns out to be porous due to oxidation in the air.

At present, it is convenient to perform welding work on connecting electrical wires inverter welding machine, since it has a small volume and weight, which allows the electrician to work on a ladder, for example, under the ceiling, hanging the inverter welding machine on his shoulder. For welding electrical wires, a graphite electrode coated with copper is used.

In a joint obtained by welding, an electric current flows through a monolithic metal of the same type. Of course, the resistance of such compounds is record low. In addition, such a connection has excellent mechanical strength.

Of all the known methods of connecting wires, none of them can be compared with welding in terms of durability and conductivity of the contact. Even soldering is destroyed over time, since a third, more fusible and loose metal (solder) is present in the connection, and there is always additional transition resistance at the interface between different materials and destructive chemical reactions are possible.

Soldering is a method of joining metals with another, more fusible metal. Compared to welding, soldering is easier and more affordable. It does not require expensive equipment, is less flammable, and the skills to perform a good quality soldering will require more modest than when making a welded joint. It should be noted that the metal surface in air is usually quickly covered with an oxide film, so it must be cleaned before soldering. But the cleaned surface can quickly oxidize again. To avoid this, chemicals are applied to the treated areas - fluxes that increase the fluidity of the molten solder. Thanks to this, the soldering is stronger.

Soldering is also the best way to terminate copper stranded wires into a ring - the soldered ring is evenly covered with solder. In this case, all wires must completely enter the monolithic part of the ring, and its diameter must correspond to the diameter of the screw clamp.

The process of soldering wires and cable cores consists in coating the heated ends of the connected cores with molten tin-lead solder, which after hardening provides mechanical strength and high electrical conductivity of the permanent connection. The soldering should be smooth, without pores, dirt, sagging, sharp solder bulges, foreign inclusions.

For soldering copper conductors of small cross sections, solder tubes filled with rosin are used, or a solution of rosin in alcohol, which is applied to the junction before soldering.

To create a high-quality soldered contact connection, the cores of wires (cables) must be carefully tinned, and then twisted and crimped. The quality of the soldered contact largely depends on the correct twisting.

After soldering, the contact connection is protected by several layers of insulating tape or heat shrink tubing. Instead of an insulating tape, the soldered contact connection can be protected with an insulating cap (PPE). Before this, it is desirable to cover the finished joint with a moisture-resistant varnish.

The parts and solder are heated with a special tool called a soldering iron. A prerequisite for creating a reliable connection by soldering is the same temperature of the soldered surfaces. Of great importance for the quality of soldering is the ratio of the temperature of the soldering tip and the melting temperature. Naturally, this can only be achieved with the right tool.

Soldering irons vary in design and power. To perform household electrical work, a conventional electric soldering iron with a power of 20-40 W is quite sufficient. It is desirable that it be equipped with a temperature controller (with a temperature sensor) or at least a power controller.

Experienced electricians often use the original method for soldering. A hole with a diameter of 6-7 mm and a depth of 25-30 mm is drilled in the working rod of a powerful soldering iron (at least 100 W) and filled with solder. When heated, such a soldering iron is a small tin bath, which allows you to quickly and efficiently solder several stranded connections. Before soldering, a small amount of rosin is thrown into the bath, which prevents the appearance of an oxide film on the surface of the conductor. The further soldering process consists in lowering the twisted joint into such an impromptu bath.

Screw terminals

One common way to create a contact is to use screw terminals. In them, reliable contact is ensured by tightening the screw or bolt. In this case, it is recommended to attach no more than two conductors to each screw or bolt. When using stranded wires in such connections, the ends of the wires require preliminary tinning or the use of special lugs. The advantage of such connections is their reliability and collapsibility.

By appointment, terminal blocks can be through and connecting.

Designed to connect wires to each other. They are commonly used for switching wires in junction boxes and switchboards.

They are used, as a rule, to connect various devices to the network (chandeliers, lamps, etc.), as well as when splicing wires.

When connected with screw terminals wires with stranded conductors, their ends need to be pre-soldered or crimped with special tips.

When working with aluminum wires, the use of screw terminals is not recommended, since aluminum conductors, when tightened with screws, are prone to plastic deformation, which leads to a decrease in the reliability of the connection.

Recently, self-clamping terminal blocks of the WAGO type have become a very popular device for connecting wires and cable cores. They are designed to connect wires with a cross section of up to 2.5 mm2 and are designed for an operating current of up to 24 A, which allows you to connect a load of up to 5 kW to the wires connected by them. Up to eight wires can be connected in such terminal blocks, which greatly speeds up the wiring as a whole. True, compared to twisting, they take up more space in soldered boxes, which is not always convenient.

It is fundamentally different in that its installation does not require any tools and skills. The wire, stripped to a certain length, is inserted into its place with little effort and is securely pressed by a spring. The design of a screwless terminal connection was developed by the German company WAGO back in 1951. There are other manufacturers of this type of electrical products.

In spring-loaded self-clamping terminal blocks, as a rule, the effective contact surface area is too small. At high currents, this leads to heating and release of the springs, resulting in a loss of their elasticity. Therefore, such devices should be used only on eyeliners that are not subjected to heavy loads.

WAGO manufactures terminal blocks for both DIN rail mounting and for screwing to a flat surface, but building terminal blocks are used for installation as part of home wiring. These terminal blocks are available in three types: for junction boxes, for fixture fittings and universal.

WAGO terminal blocks for junction boxes allow you to connect from one to eight conductors with a cross section of 1.0-2.5 mm2 or three conductors with a cross section of 2.5-4.0 mm2. And terminal blocks for fixtures connect 2-3 conductors with a cross section of 0.5-2.5 mm2.

The technology for connecting wires using self-clamping terminal blocks is very simple and does not require special tools and special skills.

Connecting insulating clips

One of the most popular connecting products among electricians is connecting insulating clamp (PPE). Such a clamp is a plastic case, inside of which there is an anodized conical spring. To connect the wires, they are stripped to a length of about 10-15 mm and folded into a common bundle. After that, PPE is screwed onto it, rotating clockwise until it stops. In this case, the spring compresses the wires, creating the necessary contact. Of course, all this happens only when the PPE cap is correctly matched to its face value. Using this clamp, it is possible to connect several single wires with a total area of ​​2.5-20 mm2. Naturally, the caps in these cases are of different sizes.

Depending on the size, PPE have certain numbers and are selected according to the total cross-sectional area of ​​the twisted cores, which is always indicated on the package. When choosing PPE caps, one should be guided not only by their number, but also by the total cross section of the wires for which they are designed. The color of the product has no practical significance, but can be used to mark phase and neutral conductors and ground wires.

PPE clamps greatly speed up installation, and due to the insulated housing, they do not require additional insulation. True, their connection quality is somewhat lower than that of screw terminal blocks. Therefore, ceteris paribus, preference should still be given to the latter.

The twisting of bare wires as a method of connection in the "Electrical Installation Rules" (PUE) is not included. But despite this, many experienced electricians consider a correctly performed twist as a completely reliable and high-quality connection, arguing that the contact resistance in it practically does not differ from the resistance in the whole conductor. Be that as it may, a good twist can be considered one of the stages of connecting wires by soldering, welding or PPE caps. Therefore, high-quality twisting is the key to the reliability of all electrical wiring.

If the wires are connected according to the “how it happened” principle, a large contact resistance can occur at the point of their contact, with all the negative consequences.

Depending on the type of connection, twisting can be performed in several ways, which, with a small transient resistance, can provide a completely reliable connection.

First, the insulation is carefully removed without damaging the wire core. Sections of veins exposed to a length of at least 3-4 cm are treated with acetone or white spirit, cleaned with sandpaper to a metallic sheen and tightly twisted with pliers.

The crimping method is widely used to make reliable connections in junction boxes. In this case, the ends of the wires are stripped, combined into appropriate bundles and crimped. The connection after crimping is protected with electrical tape or heat shrink tubing. It is non-detachable and does not require maintenance.

Crimping is considered one of the most reliable ways to connect wires. Such connections are made using sleeves by continuous compression or local indentation with special tools (press tongs), into which interchangeable dies and punches are inserted. In this case, the indentation (or compression) of the sleeve wall into the cable cores occurs with the formation of a reliable electrical contact. Crimping can be done by local indentation or continuous compression. A solid crimp is usually made in the form of a hexagon.

It is recommended to treat copper wires with a thick lubricant containing technical petroleum jelly before crimping. This lubrication reduces friction and reduces the risk of damage to the core. A non-conductive lubricant does not increase the contact resistance of the connection, since, if the technology is followed, the lubricant is completely displaced from the contact point, remaining only in the voids.

For crimping, manual press tongs are most often used.

In the most common case, the working bodies of these tools are dies and punches. In the general case, the punch is a movable element that produces a local indentation on the sleeve, and the matrix is ​​​​a figured fixed bracket that perceives the pressure of the sleeve. Matrices and punches can be replaceable or adjustable (designed for different sections).

When installing ordinary home wiring, as a rule, small crimping pliers with curly jaws are used.

Of course, any copper tube can be used as a sleeve for crimping, but it is better to use special sleeves made of electrical copper, the length of which corresponds to the conditions for reliable connection.

When crimping, the wires can be inserted into the sleeve both from opposite sides until mutual contact is strictly in the middle, and from one side. But in any case, the total cross section of the wires must correspond to the inner diameter of the sleeve.

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The connection of wires in the junction box requires special care in execution. 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 separate rooms of the apartment or house. Moreover, in each room there is usually not one, but several connection points (sockets and switches). To standardize the joining of conductors and concentrate them in one place, junction boxes are used (their other names are: "junction" or "branching"). The boxes contain cables from all consumer devices.

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

Junction boxes are classified according to the type of installation. There are internal junction boxes and external ones. A niche is provided for flush-mounted boxes in the wall. Only the cover remains on the surface, which is installed flush with the finishing material. It is allowed to cover the cover 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 junction 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 to secure the corrugated hose. The presence of such a hose or plastic pipe greatly facilitates 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 the strobe, you will need to break the layer of plaster, which is much more laborious.

The use of junction boxes entails the following positive results:

1. The maintainability of the power supply system is increased. Since all connections are easily accessible, it is much easier to find the damaged area.
2. The vast majority of faults are found at the joints. Since all connections are concentrated in one place, it is easier to carry out routine inspections.
3. Thanks to junction boxes, the degree of fire safety increases.
4. Using junction boxes saves money and reduces labor costs when laying cables.

Ways of connecting conductors

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

• the material from which the cores are made (steel, copper, aluminum);
• environmental conditions (street / indoor, work in the ground or water, etc.);
• number of wires;
• matches or mismatches of the cross section of the cores.

Based on these parameters, the most appropriate method is selected.

The following methods of connecting wires in the junction box are used:

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

Below we consider the features of each of these methods.

Terminal blocks

Terminals are devices made of plastic, the inside of which contains a brass sleeve. 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 fix them tightly with screws. This method of docking 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 incompatible materials such as copper and aluminum.

Disadvantages of the method:

1. The pads offered for sale are often of low quality, which is detected during docking and forces the product to be rejected.
2. Only two wires are allowed.
3. Terminal blocks are not suitable for aluminum or stranded wires, as aluminum is brittle and stranded conductor strands are too thin.
4. Although the method is reliable, a better connection can be obtained, for example, by soldering.

Terminals Wago

Wago spring terminal blocks are one of the most popular devices used when 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 fix the conductor, while maintaining its integrity. Before using Wago, you need to remove the insulating layer. Next, the wires are sent to the shoe hole.

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

Advantages of Wago spring pads:

1. It is possible to connect both conductors from one metal, and dissimilar materials.
2. There is the possibility of joining multiple cores (three or more).
3. When fixing stranded conductors, thin conductors do not break.
4. The pads are small in size.
5. Working with pads does not take too much time, the process is not labor-intensive.
6. The fastening is of high quality.
7. The block has a hole for an indicator screwdriver to control the functioning of the electrical network.

Wago has one drawback - the high cost of products.

Self-Isolating Clamps (PPE)

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

The advantages of PPE include the following characteristics:

1. Low cost.
2. Products are made of non-combustible plastic, therefore, there is no danger of spontaneous combustion of electrical wiring at the docking point.
3. Easy installation.
4. A wide variety of color shades, which allows you to mark the phase, zero and ground with colors.

The disadvantages of PPE include:

• low fixing and insulating qualities;
• impossibility of application for connection of aluminum and copper conductors.

Crimping with sleeves

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

Benefits of pressing:

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

Disadvantages of pressing:

1. The sleeve cannot be replaced after it has been removed - this is a one-time mount.
2. The connection will require the use of a specialized tool (crimping tongs, pipe cutter).
3. Crimping aluminum and copper wires is possible only with the help of a specially designed sleeve.
4. The work is labor intensive.

Soldering

The connection by soldering is considered the highest quality of all possible. Before docking, it is necessary to clean the conductors well. Next, the bare ends are processed with molten solder, after which the cores are immersed in the bath. When the cores have cooled, insulating material (cambric or electrical tape) is applied to them.

Note! The cooling process should not take place in cold weather, because as a result of too rapid cooling, the material will be covered with microcracks, which will greatly impair the quality of the fixing of the conductors.

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

Disadvantages of the technique:

1. A specialized tool is required, as well as skills in handling it.
2. The job requires a lot of work.
3. The connection is one-piece, that is, one-time.
4. There are restrictions on the use of soldering, which are detailed in the PUE.
5. Over time, soldering resistance increases, which affects the form of voltage losses and electrical conductivity.

Thus, despite the reliability of the docking, 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.

Twisting

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

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

Clamp type "nut"

"Nutlet" is a cable clamp with two plates and four bolts in the corners. Before connecting, the insulation is removed from the wires. Further, the conductors are fixed in the plate and covered with a carbolite sheath.

Nut Benefits:

1. Low costs.
2. Installing the "nut" is not very difficult.
3. Connection of dissimilar materials (aluminum and copper) is possible.
4. Quality insulation.

The disadvantages of the method:

1. Fasteners loosen over time and need to be tightened regularly.
2. "Nut" is not the best way to mount in the junction box due to the excessive dimensions of the connection.

Bolted connection

Bolting is a very simple but effective way of joining conductors to each other. To do the job, you only need a bolt, three washers and a nut. The wiring diagram in the junction box with a bolt is shown in the picture below.

A washer is threaded onto the bolt thread. Next, the core is wound (previously, the insulation should be removed). After that, 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.

Bolted connection has the following advantages:

• low cost;
• ease of implementation;
• the possibility of joining copper and aluminum products.

Disadvantages of joining conductors with bolts:

1. Poor fixation quality.
2. You will need a lot of insulating material.
3. The bolt is too large and may not fit in the junction box.

Solving other problems

The connection of stranded wires has a number of features.

Connecting multiple wires

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

• Wago terminal blocks;
• sleeve crimping;
• soldering;
• twists;
• insulating tape.

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

Docking lived with different sections

To combine conductors of unequal cross-section 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 firmly fix the cores with a screw or lever.

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

Cores with different cross-sections can also be fixed by soldering.

Splicing of stranded and solid conductors

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

The procedure for carrying out work in land and water

It is not uncommon that there is a need to lay electrical wiring underground or under water. Let us briefly dwell on the features of performing electrical work in these conditions.

Wires can be laid in water, for example, when installing a submersible pump. In this case, you need to solder the ends of the wires. Next, the connection is processed with insulating material (hot-melt adhesive), and heat shrink is put on top. If the technology is followed, the joint will turn out to be very reliable and safe. However, carelessness should be allowed, and the matter will end in a short circuit.

Ground wiring is protected in the same way as described above, however a more advanced technique can be used to obtain a secure connection. 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 an underground highway in a durable box or pipe to prevent acts of sabotage by rodents. Damaged cable ends are best spliced ​​with sleeves.

Basic wiring diagrams

Above, we talked in sufficient 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 outlets is usually separated into an independent line. There are three wires in the box, each of which has a color inherent in its purpose. Brown is usually phase, blue is zero, and green/yellow is ground. In some cases other colors are used. For example, phase is red, zero is blue, ground is green.

The wires before laying are laid out in full length and cut so that they have the same length. It is necessary to have 10-12 centimeters of stock - just in case. The connection of conductors is carried out by one of the methods described above.

If only a pair of wires is involved (where ground is not used), then we are talking about a neutral and a phase. If the conductors are of 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 the 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 work only when the contacts of the switch are closed.

Connecting a two-button switch

In two-gang switches, the circuit is somewhat more complicated. A three-wire cable should go to the switch that serves two groups of lighting fixtures (if earth is not used). One conductor is intended for the common contact of the switch, the remaining two are directed to the exit of the buttons. The phase is combined with the common contact of the switch. Zero wires from the input and two groups of lighting fixtures are connected. Phase wires from lighting devices 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 another lamp.

The most important elements of any electrical network are the connection points of the wires. The reliability and durability of the electrical network depends on the quality and correctness of these works. Unfortunately, such low-quality work cannot be diagnosed, the shortcomings appear when the system is loaded. At the same time, a poor-quality connection begins to warm up and this often leads to a fire, which is far from always possible to localize.

This review describes the main types of wire connection with a photo, their classification and application.

Regulatory documents

There are many ways to connect wires. Their use or prohibition is regulated by the current rules for the installation of electrical installations (PUE), which are approved by the Ministry of Energy of the Russian Federation. They must not conflict with the current document.

The regulatory framework is adjusted over time, as there is a steady increase in electricity consumption and some types of connections do not provide the reliability required in modern conditions. For example, in accordance with the current rules, twisting without additional fixation, which was widely used earlier, cannot be used, since there are better and no less affordable modern technologies.

In order to determine how best to connect the wires, it is necessary to study all available technologies, determine their advantages and disadvantages. First of all, they are classified according to the need for additional skills to carry out the work. They do not require fastening using terminals, various spring clips, bolts and PPE caps.

Each solution has its own advantages and disadvantages. First of all, they differ in ease and reliability of installation. In general terms, we can say that quickly made contacts using various terminals and clamps can weaken over time and lead to accidents. High-quality contacts made using sleeves, soldering or welding require more time and are not disassembled.

Thus, reliability is directly proportional to the complexity. Before connecting the wires with your own hands, you should read the instructions. It should be noted that in all works, preliminary cleaning of materials from the oxide film is required.

Specifications of the various options

Let's take a closer look at wiring methods that require additional tools. They allow you to get reliable connections designed for high currents.

Soldering

This type of connection of electrical wires is widespread. Most often it is used for copper conductors. To do this, you need a soldering iron, tin and rosin. The tip is wetted with a small amount of molten solder, which is then transferred to the twist when it is heated. Residues of rosin evaporate when heated. Before soldering several cores, it makes sense to tin each of them separately.

Such solutions are very convenient to use for conductors of small diameter, both single-core and with a large number of cores. Work should be done as quickly as possible so as not to melt the plastic insulation. Aluminum can also be joined in this way, but this requires a special flux and solder.

Welding

Welding withstands high currents and has mechanical strength. So you can connect both copper and aluminum. It is very suitable for large diameter veins. They are twisted into one bundle, and using a welding machine, a large current is passed through it, which melts the metal at the end of the twist.

In order to get a neat contact, you must first practice and select the parameters of the welding equipment. This can be done using unnecessary trimmings. It is necessary to melt the metal without damaging the insulation.

Crimping

Crimping is performed using sleeves and a special tool. They are made of copper and aluminum. This operation is quite simple, but requires the selection of sleeves of the right size and a special tool to compress them.

The work is quite simple: the cores are folded into a bundle, inserted into the sleeve and crimped in several places. It can withstand large current. The biggest difficulty lies in the selection of sleeves of the desired diameter: they should not be too large or small.

Twisting

As described above, this method cannot be used without additional fixation. Since it does not allow you to create a reliable contact. Twisting is used in combination with soldering, welding, crimping or the use of PPE. Before fixing, the wires are twisted.

The three methods described provide for their subsequent electrical isolation. To do this, use insulating tape for electrical work or heat shrink tubing. They are made of a polymeric material, which allows, when heated, to reduce their diameter by several times.

Products of various nomenclature are produced. First of all, it is necessary to highlight the need to use light-resistant materials outdoors. For shrinkage, it is best to use an industrial hair dryer or gently heat the polymer tube with a soldering iron.

For reliability, after installing the first tube, mount a second tube of a larger diameter. After shrinkage, the material must securely close the ends of the contact.

The following solutions require no additional tooling and make it easy to make the right wire connection at an entry-level skill level.

Terminal blocks

Previously, they were widely used due to their low cost and reliability. On it you can connect wires of different sections. They can be copper or aluminum, can consist of one or many strands. They are clamped with screws on the terminal block.

The disadvantage is that they are connected only in pairs. For a larger number of connections, special jumpers are required. There are other options for easier connection.

Connecting insulating clips

One of them is the use of PPE caps. This is a plastic cap inside which a metal spring is installed. It is wound onto a bundle, twisting them, plastic serves as electrical insulation. Such contact is very reliable. There is a domestic development of the KZT company, which is put on directly on the twist.

Wago clamps

This type of connection conquered the market with its convenience and ease of use. They connect all kinds of conductors. Clips are issued on various number of connections.

The disadvantage is that there is a spring in the design, which can weaken over time, which can lead to an accident and fire. Therefore, you should purchase only original, branded products.

Bolted fasteners

This type of fastening is classic, it allows you to connect copper with aluminum. Consists of a bolt with a nut and three washers. It can be made independently in the absence of other connectors.

Conclusion

The choice of how best to connect the wires depends on their type, budget and time. If you follow the rules of the PUE, then you can make safe and reliable contacts that will last for many years. It should be remembered that in any case, these works must be carried out as carefully and prudently as possible, without haste.

Photo of the wire connection process

Today, there are many ways to connect wires in a junction box.

Here are some factors that determine the choice of connector:

1. Core material (copper or aluminium).
2. Working conditions (outdoors, in an apartment, in water, in the ground, in the floor, normal conditions).
3. Number of conductors (two, three, four, etc.).
4. The cross section of the veins (the same, different).
5. Core structure (single-wire or multi-wire).

Based on these factors, the most appropriate and correct method is selected. To begin with, consider the materials with which you can connect electrical wires in a junction box.

Existing methods

The following connection options are considered the most popular and effective:

• use of terminal blocks;
• installation of spring terminals (wago);
• fixation with PPE (plastic caps);
• sleeve crimping;
• soldering;
• twist;
• installation of "nuts";
• use of bolts.

Consider the essence, advantages and disadvantages of each method!

Installing PPE caps

PPE stands for connecting insulating clamps. Products are ordinary plastic caps with a special spring inside, which holds the wires.

Most often, such caps are used to connect cores in junction boxes.

Benefits of using these products:

• low cost of PPE;
• the caps are made of non-combustible material, so there will be no twisting at the place;
• fast installation;
• caps have a wide range of color shades. For example, if the wires do not have, you can mark with the help of PPE (using a white, blue and green cap).

Disadvantages:

• relatively poor quality of insulation and fixation;
• it is impossible to combine aluminum with copper.

Crimping with special sleeves

Twisting and insulation

The old "grandfather" method consists in twisting the cores together. The essence of the work is that the conductors are stripped and carefully twisted with pliers, after which the place of twisting is isolated.

Advantages:

• ease of electrical work;
• no material costs.

Disadvantages:

• poor quality of fastening lived;
• connection of aluminum and copper products is unacceptable.

We figured out the existing methods of connecting wires in the box, now we will consider the remaining, important issues of this topic.

What if there are several wires?

When bonding two contacts, problems usually do not arise. But what if you need to combine three, four or more at the same time?

• using wago terminal blocks;
• sleeve crimping;
• soldering;
• twisting using sizov;
• twisting and winding with electrical tape.

The order of connecting the wires for each of the methods we discussed in detail above. We strongly recommend that you use the first option, because. it is one of the most modern and efficient. At the same time, the cost of the vag is not too high, and the wiring has been serving for more than 30 years.

What to do if the conductors are of different sections?

To connect conductors of different cross-sections in a junction box, it is recommended to use all the same terminal blocks of the car, or a cheaper option - ordinary terminal blocks. In this case, it is necessary to carefully tighten the wires with a screw or fix with a flag, and that's all, the work is over.

Please note that if the wires are made of different materials, then it is necessary to use special pads with paste inside, which will prevent the wires from oxidizing. These pads include wago products.

Also, conductors of different sections can be fixed by soldering.

Combining stranded and solid wires

Connecting single-core and stranded wires separately does not have any features, so you can use any of the methods listed above.

In order to carry out bonding, it is necessary to choose one of two options: car terminals or soldering. It all depends on your preference, the advantages and disadvantages of each method we have provided.

How to work in water and land

During electrical work, a situation often occurs when it is necessary to fasten electrical wiring under water or in the ground. Now we will briefly consider the features of each of the cases!

In water (for example, when installing a submersible pump), it is recommended to use the following technology. To begin with, the ends are soldered, after which the soldering point is carefully insulated with hot-melt adhesive, over which it is put on. If everything is done efficiently and conscientiously, the joint will be tight and safe. Otherwise, power outage may also occur.

To connect an electrical wire in the ground (for example, after it has been mechanically damaged), it is recommended to use the method provided above (hot glue and heat shrink), but it is better to protect yourself and use the following method. Clamp the ends of the cable with a terminal block, install a sealed junction box, and then carefully fill the box with a special silicone sealant. We draw your attention to the fact that the underground track must be additionally placed in a pipe or box in order to ensure reliable!