The order of connecting the wires is 1 5 mm2. Wire connection methods

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Any man strives to ensure that the power supply is own home or apartment was of high quality, uninterrupted and reliable. Therefore, when carrying out electrical installation work During construction or renovation, the connection must be made correctly electrical wires. But in Everyday life 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 for transfer electrical energy use copper, aluminum and steel. 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 quite 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 in a reliable way, which 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 obtain 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 wire. 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 known method connecting electrical wires is by 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’s good if this defect is discovered in time and the joining point 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 must first 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. Very good option Insulation is carried out using 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 electric wires 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 wire joining 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.

The electrician must have certain qualifications and be able to use a soldering iron, because during the work it is necessary to strictly observe 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 over the cleaned surfaces several times.
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 too.

The main disadvantage of this type of wire connection is the presence welding machine and devices for similar 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 strip the veins 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.

Any connection scheme electrical wiring It has a large number of connections. They are considered to be the “Achilles heel” of any electrical circuit.

That's why correct installation connections should be given the closest attention. And compliance with the rules of PUE (Electrical Installation Rules) when installing connections will allow you to eliminate fires and other unpleasant situations associated with your electrical wiring.

First of all, let's deal with possible types electrical connections. There are two of them: serial and parallel. Each of them has its own purpose and is used to implement various tasks.

Serial connection

First of all, let's look at the serial connection. It is used quite rarely, but also has its advantages. A connection is called serial in which the neutral wire of the first electrical receiver is phase to the second electrical receiver in the circuit. This can be seen better in the photo below.
With this type of connection, the supply voltage is divided equally between each electrical receiver. That is, if the network is 220V, we connect two lamps with a serial connection - each of them will receive 110V. If you connect three lamps, then 73V, and so on. This feature of series connection is often used in garlands.
The disadvantages of a serial connection include the fact that if a wire breaks in any section, the entire circuit stops working. That is, if one of the three bulbs connected in series burns out, none will light up.

Please note that when connecting in series, for example 220V lamps, the lamp with lower resistance will burn brighter. If you screw in two lamps: one 60W, and the other 200W, then the light will shine brighter lamp with a power of 60W.

Parallel connection

So:

In most cases electrical circuits The wiring connections are designed for parallel connection. With this type of connection, one phase and one neutral wire from the supply network is supplied to each electrical receiver. Again, this can be seen better in the picture below.
This type of connection is used to connect 99% of electrical appliances. In this case, a break in the wire connecting to an electrical appliance de-energizes only this electrical appliance. The supply voltage corresponds to the specified one and can only change due to the connection of high-power devices.
The disadvantages of a parallel connection include only a larger number of wires, as well as an increased likelihood of getting confused with a large number of connections. But this factor can be easily excluded if you read these instructions to end.

Wire connection methods

In accordance with clause 2.1.21. PUE, the connection of wires can only be done by welding, soldering, crimping and squeezing. As you can see, the favorite method of home-grown electricians, twisting, is not included in the list of permitted connection methods.

And of all the permitted methods presented, the most optimal for use at home is compression. This can be a screw, bolt or spring connection.

So:

For the installation of bolted and screw connections, the industry now produces a large number of a wide variety of terminal connections. Their price is not high, and the ease of installation is at a high level.
Separately, I would like to say about spring terminals. I myself am not a supporter of springs, spacers and similar connections, but I once had the opportunity to witness the testing of one of these terminal blocks.
These were WAGO terminals. In the test setup, we gradually increased the current flowing through the terminal until our 4mm2 copper wire burned out. In this case, the current value was 100A. After that, we took out the terminal block and did not find any defects on it. This made me change my opinion about such spring terminal blocks, and therefore I advise you to take a closer look at them.
It is also worth noting that a separate advantage of such terminal blocks is the ability to connect aluminum and copper wires. Under normal conditions, this can only be done through a brass insert.

Electrical wiring options

Now let's figure out what the electrical wiring should be and how to connect the wires. To disconnect a single-phase network, it is necessary to use a three-wire wire.

In this case, the standards from clause 1.1.29 of the PUE should be applied to facilitate installation and reduce the likelihood of wires being tangled.

Three-core wire should be used with the following wires:

Phase wire– the color designation for a single-phase network is not standardized. For a three-phase network, yellow, green, red are phases A, B and C, respectively.

Note! For a three-phase circuit, PUE standards standardize not only the color scheme of the designation of each phase, but also their location in distribution panels of different designs.

Neutral wire– for any networks a blue conductor must be used. When designating busbars or terminal blocks, the symbol “N” is used.
Ground wire– in any networks, a wire with longitudinal yellow-green stripes must be used. When designating busbars and terminal blocks, the grounding symbol is used.

Connection in the distribution panel

Now let's look at the types of electrical wiring connections in different parts of our electrical network.

Let's start with the distribution panel:

First, let's deal with the phase wire. It must be connected via a protective device. These can be fuses, plugs, but most often circuit breakers are used. The power wire to circuit breakers is usually supplied from above, but you connect from below.
The neutral wire, according to the PUE standards, should not have switching devices. Therefore, usually a separate terminal block is organized for it in the side of the panel. We connect the blue wire of our wire to it.
The same rule applies to the ground wire. Only for it you should create a separate terminal block. We connect our yellow-green wire to it.

Let us separately dwell on the connection of the RCD. To do this, we need to use not only the phase, but also the neutral wire. And the circuit largely depends on the location of the RCD installation.

If you install RCDs on all groups of your electrical network:

In this case, the phase and neutral wires from the meter are connected to the RCD inputs. It is important here not to confuse and connect the neutral wire to the terminal marked “N”. Otherwise the RCD will not work.
We connect the phase wire at the output of the RCD to all circuit breakers that supply individual groups.
We connect the neutral wire at the output of the RCD to a bus or terminal block, from which the neutral wires of all groups are connected.

If you install an RCD on a separate group:

In this case, the phase wire for the RCD input is taken from the group circuit breaker.
The neutral wire for the RCD input is taken from the neutral bus of your distribution panel.
From the RCD terminals, the neutral and phase wires go directly to consumers.

Connection in junction box

Connecting the electrical wiring to the blocks, subject to the above standards, will also prevent you from getting confused. The only difference here is the connection of lamps and sockets, but they are insignificant.

When connecting sockets, we just need to use terminals to make a branch of the phase, neutral and ground wires:

To do this, the incoming wire is cut and each core is connected to a separate terminal block. To connect one socket you need three terminals, two sockets - four, three - five, and so on.
Now we connect the phase wire of the incoming wire to one terminal. The group wire going to other connections is connected to the second terminal. We attach the phase wire going to our socket to the third terminal.
We perform identical operations with the neutral and ground wires.

Connecting lamps is somewhat complicated due to the presence of a switch.

If you volunteered to connect the lamps with your own hands, then at the first stage we do the same operations as when connecting sockets. That is, we cut the cable and connect each core to different terminal blocks. You can also immediately connect the wire going to other electrical receivers of this group.
According to the PUE standards, the lighting circuit breaker must disconnect the phase wire. Therefore, from the terminal block of the phase wires we make a connection to the switch.
If you have a one-button switch, then the output from the switch will be one wire. If there are two or more buttons, then two or more, respectively. We'll look at a one-button switch to make it easier to provide information. For two, three or more push-button switches, the connection diagram is identical.
The wire connected to the switch terminal is sent back to the junction box. Here we install another phase terminal block, to which our wire is connected.
Now take a three-core wire, which is connected directly to the lamp. The phase core of this wire is connected to the phase terminal block of the wire coming from the switch. The neutral conductor is connected to the terminal block of the neutral conductors, and the grounding conductor is connected to the terminal block of the grounding conductors. That's it, the connection of our lamp is completed. If you watch the corresponding videos, this process will become even more clear to you.

conclusions

We hope that our instructions will allow you to easily connect an electrical network of any complexity. After all, basic compliance with the rules of the PUE can significantly simplify this process and eliminate the possibility of error.

In the article we will talk about methods for connecting wires in junction boxes, and talk about preparing conductors for connecting household appliances and installation products.

The electrical wiring of residential premises consists of many elements, these are various current-carrying conductors (cables), protective devices, electrical installation products, individual current consumers. In order to assemble all the components of the system into a single circuit and at the same time make the power supply functional and safe, it is necessary to qualitatively connect them together, or, as they say, switch them (switching refers to the processes that occur when electrical circuits are closed or opened).

At first glance, it may seem to an unprepared person that there shouldn’t be anything complicated here. But when working with electricians “on a whim,” it doesn’t matter whether we’re moving a single outlet, connecting a lamp, or assembling a complex control system, we take a serious risk. Experienced electricians know that electrical installation is primarily a “struggle for contact,” since it is an open circuit, and not a short circuit, that is the most common problem encountered. Obviously, the connection points in the circuit (terminals, twists) are the most vulnerable, since at these points the mechanical density of the contact can weaken (the contact area decreases), and an oxide film with a very high resistance forms on the conductors over time. Poor contact causes heating of current-carrying conductors and sparking at switching points - these are the consequences of the occurrence of transient contact resistance. Complete burnout of the wire and loss of power to the area when household appliances do not work or the light goes out is unpleasant, but the problem is solved. It’s worse if the insulation of the wires heats up and is destroyed, which threatens to injure a person. electric shock or the occurrence of a fire.

Recently, the load on wiring has increased significantly, so switching is now subject to even more stringent fire and electrical safety requirements. However, if previously there were not many connection options, now reliable modern devices have appeared that make wiring easier. In addition to welding and soldering with subsequent tape insulation of the twist, PPE caps, various terminal screw and spring blocks, all kinds of insulated and open lugs, and branch clamps can be used in a household network. These products will help you efficiently connect wires in junction boxes, assemble a distribution board, connect household appliances and lighting fixtures, sockets and switches.

There are several key objective factors that influence the choice of switching method, or the use of specific devices. Let's just list the main ones:

power and number of consumers (read: total cross-section of conductors);
material of current-carrying conductors (copper or aluminum);
cable type (flat or round, hard or soft stranded, single or double insulated);
purpose of the node (group or single branch, end connection);
the presence of mobility of wires or vibrations near them;
elevated temperature, humidity;
indoor or outdoor use.

Connecting wires in junction boxes

According to the provisions of the PUE, branching of household network wires can only be carried out in a distribution (junction) box. During operation of the wiring, junction boxes allow you to quickly get to the ends of any individual branch and, if necessary, detect which of them is broken or has a short circuit. You can also always inspect the condition of the contacts inside the box and make them Maintenance. Modern PVC boxes are used for open and hidden wiring; they have sufficient reliability and expanded functionality: they are easily installed on various surfaces, convenient for electrical installation manipulations.

In order to always have access to the connected wires, all distribution boxes are placed on free sections of the walls; it is most rational to install them on the side of the corridors, for example, above the door of the powered room. Naturally, boxes cannot be tightly plastered or sewn inside building frames; the permissible decorative maximum is a thin-layer finish on top of the lid (paint, wallpaper, decorative plaster).

For the arrangement of lighting and power circuits (outputs and sockets), it is recommended to use separate distribution boxes for each room. This divided power supply makes it possible to make the electrical wiring of the home more balanced and safe, since the “lights” and “sockets” differ in workloads and operating conditions, and they are subject to different requirements. Moreover, it is much easier to upgrade or repair the wiring later, and not always all the wires in a room can be properly laid out in one housing.

Switching wires in any distribution box can be carried out according to the same principle. In most cases, “twisting” is initially used, but simply wrapping the conductors with electrical tape is not enough - it must be reinforced with additional operations that are designed to increase the contact area of the connected current-carrying conductors and reduce the oxidation of materials. Clause 2.1.21 of the PUE offers the following options:

soldering
welding
crimping
crimping (bolts, screws, etc.)

Wire crimping

The essence of this method is that twisted wires are inserted into a special metal sleeve-tip, which is compressed with hand pliers, a mechanical or hydraulic press. Crimping can be done either by local pressing or by continuous compression. This connection of wires is considered one of the most reliable. Crimping allows you to compress the cores very tightly, increasing the contact area, mechanical strength of such commutation is the highest. This method is used for both copper and aluminum wires.

The crimping process consists of several operations, each of which has its own nuances:

The wires are freed from insulation 20-40 mm from the edge, depending on the working length of the sleeve.
The veins are cleaned with a brush or emery until shiny.
Using pliers, a tight twist is made.
Based on the total twist section, a GAO sleeve with the required internal diameter, as well as a suitable punch and die.
The inside of the sleeve is treated with quartz vaseline paste (if it comes “dry” from the factory).
The twist is inserted into the sleeve.
The twist is compressed using press pliers. It is necessary that the tool rig is completely closed.
The quality of the connection is checked - the wires should not move in the tip.
The sleeve of the connected conductors is wrapped in three layers of insulating tape; for a tip thickness of up to 9 mm, a polyethylene insulating cap can be used.

Conductor crimping

Crimping of conductors can be done using terminal blocks, PPE caps or WAGO clamps.

The terminal block housing is made of plastic; inside it there are sockets with threads and clamping screws. The wires can be inserted under single screws of the terminal towards each other, or one conductor passes through the entire block and is fixed with two screws. Some distribution boxes are equipped with standard terminal blocks.

A clear advantage of switching on a terminal block is the ability to connect copper and aluminum wires, which in this case have no direct contact. The disadvantage is the need to tighten the bolt clamp if aluminum conductors are used.

PPE caps (connecting insulating clips) are also made of durable non-flammable polymer, which, being an insulator, provides mechanical and fire protection. They are forcefully wound onto the twisted conductors, then the conical metal spring located inside the cap moves apart and compresses the current-carrying conductors. As a rule, the internal cavity of the PPE is treated with a paste that prevents oxidation.

WAGO terminals for junction boxes are screwless, here the compression is performed by a spring, you only need to insert the stripped wire into the terminal. These terminal blocks are designed to connect up to eight wires with a cross-section of 1-2.5 mm 2 or three wires with a cross-section from 2.5 to 6 mm 2, while the spring acts on the conductor with a force suitable for each wire. The clamps function normally at operating currents up to 41 A for 6 squares, 32 A for 4 squares and 25 A for 2.5 squares. Interestingly, WAGO universal clamps allow you to connect wires of different sections (from 0.75 to 4 mm2) in one housing.

These devices can be designed for a hard conductor, or for a soft stranded one. Due to the fact that there is no direct contact of the connected cores, it is possible to connect copper and aluminum wires, and there is no need to regularly check the compression of aluminum. Inside, WAGO terminal blocks also have a paste that destroys the oxide film and improves contact, however, the clamps for copper conductors are not filled with contact paste. It is very easy to work with such connecting products, they are quickly installed, without the use of additional tools, they are compact and reliable. It must be said that WAGO is not the only company producing screwless spring-loaded terminal blocks.

Whatever type of crimping device is used, it is necessary to accurately select it according to the cross-section of the individual conductor or strand, since a terminal that is too large may not provide normal contact. In this case, you cannot always trust the markings - it is better to check the compliance of fasteners and conductors on site. During installation, we recommend having an assortment of crimp terminal blocks available according to standard sizes. Please note that to work with aluminum it is necessary to use contact gel; copper and aluminum conductors cannot be connected in one twist. After crimping, it is always necessary to check the strength of fixation of the cores in the terminal.

Soldering wires

Due to the technological complexity, this connection method is used quite rarely, mainly when for some reason it is impossible to use crimping, crimping or welding. You can solder wires made of aluminum and copper, you just need to choose the right solder. For branching wires with a cross-section of up to 6-10 mm2, a regular soldering iron is suitable, but larger wires will have to be heated with a portable one. gas burner(propane + oxygen). For soldering, it is necessary to use flux in the form of rosin or its alcohol solution.

The advantages of soldering are the high reliability of the connection compared to crimping (in particular, we have an increased contact area). This method is also quite inexpensive. The disadvantages of switching construction wires by soldering include the duration of the work and the technical complexity of the process.

The soldering of conductors looks like this:

the wires are stripped of insulation;
the wires are sanded with emery to a metallic shine;
a twist is made 50-70 mm long;
The core is heated with a torch flame or a soldering iron;
the metal is coated with flux;
V work area introduce solder or immerse the hot twist in a bath of molten solder for 1-2 seconds;
After cooling, the soldered twist is insulated with electrical tape or polymer caps.

Welding

Most often, electricians use contact heating welding to reliably connect wires in a distribution box. You can weld twists with a total cross-section of up to 25 mm 2 . Under the influence electric arc at the end of the twist, a fusion of the metal of several wires into a single drop is formed, and then the current during operation of the electrical circuit does not even flow through the body of the twist, but through the formed monolith. If everything is done correctly, the connection is no less reliable than a solid wire. This method has no technological or operational disadvantages, the only thing is that you need to purchase a suitable welding machine.

Welding of copper conductors is carried out permanently or alternating current with voltage from 12 to 36 V. If we talk about factory welding units, it is better to use inverter devices with sensitive adjustment welding current, which are lightweight and small in size (they are sometimes worn on the shoulder while working), can be powered from a household network. In addition, inverters provide good arc stability at low welding currents. Due to the high cost of inverters, very often electricians use homemade devices for welding, made from a transformer with a power of more than 500 W, with a secondary winding voltage of 12-36 volts. The ground and electrode holder are connected to the secondary winding. The electrode itself for welding copper conductors must be infusible - carbon, this is a factory-coated "pencil" or a home-made element from a similar material.

If a factory inverter is used for welding wires, then for wires of different sections it is recommended to set the following operating current indicators: 70-90 amperes is suitable for connecting two or three wires with a cross-section of 1.5 square meters, wires with a cross-section of 2.5 mm 2 are welded at 80-120 amperes These indicators are approximate, since the exact composition of the core may vary from one manufacturer to another - it is recommended to test the device and a certain current strength on scraps of conductors. Correctly selected indicators are when the arc is stable and the electrode on the twist does not stick.

The wire welding process includes the following operations:

the conductors are cleared of insulation (about 40-50 mm);
a tight twist is made with pliers, its end is trimmed so that the ends of the wires have the same length;
a ground clamp is connected to the twist;
the carbon electrode is brought to the end of the twist for 1-2 seconds (so that the insulation does not melt, but a solid copper ball is formed;
after cooling, the welded twist is insulated with electrical tape, heat-shrink tubing or a plastic tip.

When connecting wires, you should follow safety precautions and take fire protection measures, as for any welding work. It is recommended to use a welding mask or special glasses with a light filter; welding gloves or gloves will not be superfluous.

Connecting wires to electrical equipment terminals

Connecting household appliances and various electrical installation products are also important stage wiring switching. The performance of consumers, as well as user protection and fire safety, depend on the reliability of electrical connections in these nodes.

The technology for connecting current-carrying conductors to equipment is regulated by PUE, current SNiPs, as well as the “Instructions for terminating, connecting and branching aluminum and copper conductors insulated wires and cables and connecting them to contact terminals electrical devices" Just like branching conductors in distribution boxes, soldering, welding, crimping, screw or spring crimping are used for termination and connection. One method or another is selected primarily depending on the design of the equipment, as well as on the properties of the current-carrying conductor.

Screw crimp is used in most types modern equipment. Screw terminals are found in sockets and switches, chandeliers and lamps, in various household appliances(built-in fan, air conditioner, hob). Crimp sockets are used to supply elements of the distribution board: circuit breakers, RCDs, electric meters, and switching busbars with screw terminals are also used here.

It should be noted that convenient spring-loaded terminal blocks can also be used to connect equipment. For example, very often switches are equipped with screwless terminals; WAGO produces a special series of clamps for connecting chandeliers and lamps, as well as for switching in ASUs (terminals mounted on a DIN rail).

Please note that to connect using the crimp method, soft stranded conductors must be terminated with insulated lugs (connectors). For rigid monolithic cores, connectors are not needed. If you do not use lugs, then the soft core should be tightly twisted and tinned with solder before connecting. The size of the tip is selected depending on the cross-section of the conductor, and the geometry of the contact part is selected depending on the type of terminal on the connected device and the operating features. For example, for a clamping tunnel socket, a connector in the form of a pin is used; for fixing with a nut on a bolt, a ring or fork connector is used. In turn, the fork tip is not recommended for use if the device is moving or vibration is possible in the switching area.

If it is necessary to clamp a rigid single-wire conductor (copper or aluminum) with a cross-section of up to 10 mm 2 under the bolt, then it can be bent into a ring of a suitable radius using pliers. The ring is cleaned from the oxide film with glass sandpaper or sandpaper, lubricated with quartz-vaseline gel and put on the bolt (the ring should wrap around the bolt clockwise), after which it is covered with an asterisk washer (prevents the conductor from being squeezed out), a groover (springs the connection, prevents it from unwinding when vibrations), and the assembly clamp is tightened tightly with a nut. If a large cross-section core (from 10 mm2) must be clamped under the bolt, then a metal sleeve with a ring is placed on the conductor using the crimping method.

Switching wires is a very responsible job, and the process of assembling the circuit has a lot of nuances, which for convenience should be combined into one list:

Strip the wires using special pliers, since stripping the insulation with a knife often reduces the cross-section of the wire.
Always remove the oxide film from the conductor. Use glass sandpaper or sandpaper, use special liquids and contact paste.
Make the twist a couple of centimeters longer, and then cut off the excess.
Select the diameter of the sleeve or tip as accurately as possible.
Place the conductor under the terminal or sleeve/tip all the way to the insulation.
Make sure that the wire insulation does not get under the clamp.
If possible, insert and clamp into the tunnel screw terminal not a single soft core, but a double core.
When using electrical tape, wind it with overlapping turns in three layers, be sure to go to the insulating sheath of the conductor. Electrical tape can be replaced with heat shrink or plastic caps.
Be sure to wrap screw terminal blocks with electrical tape.
Always mechanically check the strength of the connection - tug on the conductors.
Never connect copper and aluminum directly.
Securely secure the cable near the patching area so that the wire is not pulled down and there is no mechanical stress on the connection.
Use it color coded conductors, for example, in the entire intra-house network, the brown conductor will be the phase, the blue one will be the zero, and the yellow one will be the grounding.
Adopt a single connection diagram for the installation of all devices (for example, the phase on the sockets is clamped on the right terminal, and the neutral - not on the left).
Label both ends of all wires yourself - ballpoint pen on the outer shell, at a distance of 100-150 mm from the edge of the conductor, write its purpose (for example, “pink kitchen desk” or “bedroom light”). You can also use tags or pieces of masking tape.
Leave a supply of wires convenient for installation. For distribution boxes, sockets and switches, the normal end length will be 100-200 mm. To switch the switchboard, you may need wires up to one meter long so that you can run some of them from the bottom of the box, and some from the top.
Bring external cable channels close to the distribution boxes; it is better to insert round corrugation or pipes a few millimeters into the housing.
We connect sockets in parallel, and switches in series. The switch must break a phase, not a zero.
Compress all the wires of one connected twist into a bundle and secure it with electrical tape. Inside the box, spread the insulated connections as far apart as possible.
Use only certified materials and specialized tools.

In conclusion, I would like to once again note the importance of high-quality performance of switching work. In fact, the technologies used are quite simple, you just need to make them a habit, and then the “installation culture” will appear by itself, and the wiring will be reliable and durable.

When installing electrical wiring in a house or apartment, connection of wires - the most important point . For trouble-free and safe power supply, you will need a reliable and high-quality connection of wires.

A careless attitude towards connecting wires and cables can lead to very bad consequences. It would seem that there is nothing complicated in connecting the wires, twist them, wrap them with electrical tape and everything is ready, but everything is not so simple... as popular wisdom says "Electrics is the science of contacts", and the connection of wires and cables must be carried out with all responsibility, since the percentage of accidents and damage in power supply systems due to poor-quality connection of wires is very high. No matter how good the electrical contact between the wires is, wire connections have higher resistance, which means they heat up more. And the worse the contact, the more it heats up, which will ultimately lead to melting of the insulation, a short circuit, and then a fire.

In practice, several methods of connecting wires are used, I will tell you about the most common ones.

Connecting wires by twisting

Connecting wires twisted, widespreadeverywhere, but if we turn to the main book of electricians PUE, then according to:

clause 2.1.21 “Connection, branching and termination of cables and wire cores must be done by soldering, welding, crimping or clamping (screw, bolt, etc.)”

As we can see, there is no twisted connection of wires at this point, which means twisting of wires is prohibited. But twists have always been, are and will be used to connect wires when installing electrical wiring. Yes, and well-made twisting can last for decades, but the connection of wires by twisting must be done efficiently. The technology for connecting wires and cables by twisting is quite simple:

the length of the twist must be at least 4-5 cm;
the wires to be connected, stripped of insulation, must be cleaned of the oxidized film, for example, with an ordinary knife or sandpaper;
It is necessary that the connected wires wrap around each other evenly and tightly, ensuring sufficiently reliable contact.

One “but”, problems may arise when handing over the electrical installation to the fire inspectorate, because... Connecting wires by twisting according to the PUE is prohibited. However, this applies mainly to industrial consumers, retail premises, etc.; a fire inspector will not come to your apartment or private house to inspect it.

Connecting wires by twisting- This necessary measure, when there is nothing else left, it is better to use wire connections using the methods described below.

Connecting wires by soldering

If solder twisted wires, then we get the connection of wires soldering, which guarantees reliable and high-quality contact, which has a fairly low contact resistance, high conductivity and mechanical strength. But it is important to solder the wire connection correctly; for this you need:

tin the connected wires with rosin (flux);
the solder should flow into the twist;
After the solder has cooled, you can sand it with sandpaper, because sharp edges of the solder can pierce the insulation;
insulate the wire connection.

But such connection of wires by soldering is very labor-intensive and requires certain skills. TO negative aspects rations wire connections, I would classify:

need for isolation;
complexity (not everyone knows how to solder well), and even for those who are good at soldering, doing this, for example, while standing on a stepladder or ladder, to put it mildly, is not very convenient;
if a mistake was made when connecting the wires, it will not be easy to separate them after soldering, so it is better to leave a larger supply of wires and cables;
high time consumption.

Connecting wires by welding

Connecting wires welding provides even better electrical contact between wires. But here everything is even more confusing than with soldering wires, since you need to have:

welding transformer;
welding skills;
masks (goggles) for welding, special gloves, electrodes;
construction hair dryer for heat shrink tube.

Wire connection by welding, you can perform only from homogeneous metals. Such a connection of wires can be found infrequently, our people do not really like difficulties, and many electricians do not like this method of connecting wires due to the large investment of time, but it is worth noting that connecting wires by welding is faster than soldering.

Connecting wires by crimping

Connecting wires crimping, consists of compressing the connecting sleeve (aluminum or copper tube) into which the wires are inserted with special press pliers. The wires are first stripped of insulation to the length of the sleeve, then we place the wires inside the sleeve and crimp it in two or three places for reliability. If the sleeve is much larger than the wires that need to be crimped, then you can stuff the sleeve with additional wires. We insulate the resulting wire connection using crimping tape, or better yet, heat-shrink tubing + hair dryer.

Sleeves for connecting wires by crimping, there are copper, aluminum and copper-aluminum, i.e. Crimping can be used to connect copper and aluminum wires.

Connecting wires using crimping is quite reliable if done correctly. Skills in connecting wires using crimping will also be useful to you when, for crimping NShVI bushings.

The disadvantages include the cost of pressing pliers for connecting wires by crimping and sleeves, the inseparability of connecting wires by crimping, i.e. they crimped the wire in the sleeve and “forgot” about it.

Bolted connection of wires and cables

Bolted connection wires are usually used when connecting wires made of different metals, that is, if we have one wire made of copper and the second of aluminum, a steel washer must be placed between them.

This connection of wires turns out to be very cumbersome, it is inconvenient to place it in junction boxes and insulate it. Periodic broaching is required.

Connecting wires with screw terminals

Connecting wires screw terminal blocks, as well as bolted, can be used to connect wires made of different metals. This wire connection meets the requirements of the PUE, but requires periodic tightening of screws in terminals that weaken over time, which means the contact itself weakens, which can close over time.

Periodic pulling the screw connection of wires involves, What connection access in the box should always be open, which will not look very nice in an apartment or private house. Also, when tightening the screw, you can damage the wire itself, especially the softer aluminum one. And if you need to connect a stranded wire, then you need to either solder the stripped ends of the wire or crimp it with tubular lugs.

Connecting wires with PPE caps

Connecting wires PPE caps(Connection Insulating Clamps). PPE are plastic caps with a conical spring inside, which, when twisted, compresses and fixes the wires, and the plastic PPE cap itself insulates the connection of the wires and is fire and mechanical protection.

This connection of wires is quick and simple, for its correct execution necessary:

strip the insulation from wires and cables to a length slightly shorter than the length of the PPE cap itself;
fold them into a bundle, precisely into a bundle, and not twist them;
use your hands to twist the PPE clockwise onto the bundle of wires;
tighten the PPE using pliers.

The advantages of such a connection wires and cables are obvious (no special tools required, no need for additional insulation, quick and easy), but there are also disadvantages:

Do not connect stranded wires;
the quality of such a connection will be worse than those listed above, so I would recommend using these clamps for small loads, for example, in lighting circuits.

PPE caps are divided according to the total cross-section of the wires to be twisted and are designated by numbers from 1 to 5, which indicate the number of wires to be twisted and their cross-section.

Connecting wires with self-clamping (spring) terminals

Well, in conclusion, let’s look at the simplest, most effective, convenient, and most importantly fast connection of wires - self-clamping (spring) terminals. Spring terminals from Wago are widely used, which allow you to connect wires:

without having any special skills;
there is no need to purchase special tools (soldering iron, welding transformer, press pliers);
some Wago terminals have a special paste that allows you to connect copper and aluminum wires and prevents oxidation;
no additional insulation required;
quick disconnection of the connection (press the lever and pull out the desired wire).

Wago terminals are produced for connecting wires and cables from 0.75 to 4 sq.mm., the number of connected wires is from 2 to 8. Wago terminals

Wago terminal blocks were invented in Germany. Perhaps the most significant disadvantage is their price, the average cost of a Wago terminal block for 3 wires will be approximately 11-12 rubles, so if there are a lot of distribution boxes, then the total cost of Wago terminal blocks will be considerable. You should not use Wago terminals when installing wiring with loads of more than 16 A. In general, it is better to use them maximum on the lighting line for electrical wiring in a private house or apartment, and choose Wago terminal blocks with a margin of at least a step higher.

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

About the distribution box

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

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

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

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

What are distribution boxes for?

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

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

Connecting the wires in the box

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

Method number 1. Twisting method

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

Method No. 2. Mounting caps - PPE

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

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

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

Method No. 3. Connecting conductors by soldering

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

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

Method number 4. Welding cores

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

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

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

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

Read also: Hidden electrical wiring in a wooden house

Method No. 5. Terminal blocks

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

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

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

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

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

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

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

Method number 6. Crimping

The wires in the box can only be connected by crimping using special pliers and a metal sleeve. A sleeve is put on the twist, after which it is clamped with pliers. This method is suitable for connecting conductors with a large load.

Method No. 7. Bolted connection

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

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

There are several advantages of bolted connection of conductors:

- ease of work;

- low cost;

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

However, there are also disadvantages:

— fixation of wires is not of high quality;

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

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