The principle of connecting wires. How to connect wires in a junction box How to make a twist of 4 wires

We will not prove to you that twisting wires is good way connections. Yes, it can be done well and insulated. It is also perfect as a temporary option. But according to the rules of electrical installations (PUE) in order to connect a wire or cable, ordinary twists are not recommended. Nevertheless, we will talk about it, and in very detail. Firstly, because, contrary to the PUE, most connections are made using this ancient “old-fashioned” method. Secondly, because correct twisting is the main stage of the most reliable ways wire connections - welding and soldering.

Why do you need a good twist?

Imagine that the two wires being connected are twisted together just how. Those who are familiar with electrical engineering know that transition resistance occurs at the point of contact of two conductors. Its value depends on two factors:

surface area at the point of contact;
the presence of an oxide film on the conductors.

To perform twisting, the core is exposed, the metal interacts with oxygen in the air, as a result of which the surface of the conductor is covered with an oxide film, which has a decent resistivity value.

An example of poorly executed twisting: the twisting area heats up and the insulation melts

Accordingly, if the twisting is performed poorly, the contact resistance increases, which in turn, when passing electric current through the junction will cause heating. As a result, the twisted area may become so hot that the electrical wiring may catch fire. Surely everyone has heard the phrase in their life that a fire occurred due to a fault in the electrical network.

To prevent this from happening, contact connection wires must be as durable, reliable and safe as possible. That is, the twisting must be performed so well that the contact resistance is stable and does not change over time.

Preparing wires for twisting

Remember! Never twist under voltage, even if you have a tool with insulated handles and dielectric gloves. First, turn off the power workplace by turning off the input machine for the apartment or house.

To get a good twist, you need to follow these steps exactly:

Strip the connected conductors from insulation, while avoiding damage metal surfaces conductors.
Soak a clean cloth in white spirit or acetone and wipe the exposed areas of the wires to remove any dirt.
Now with the help sandpaper strip the wires to a metallic shine.

Stranded wires

Stranding of stranded electrical wires can be done in different ways.

Parallel twist

The simplest method is parallel twisting, when both stripped wires are placed crosswise on top of each other at the place where the insulation was stripped and twisted at the same time. Such a connection provides reliable contact, but it will poorly tolerate the applied tensile force and vibration.

This method is best used for copper wires, when one of them is monolithic and the other is stranded. A monolithic wire needs to be stripped of insulation a little more than a stranded wire. After twisting, an additional bend is made from the remaining copper monolithic tail in the direction of twisting, due to this the connection is more reliable. This method is also suitable for twisting aluminum conductors with different cross-sections.

Another advantage of parallel twisting is that it can be used to connect more than two wires at the same time.

Serial twisting

With the sequential method, each connected wire is wound onto another. The reliability and contact of such a connection will be optimal, but this twist can only be used for two wires, no more.

Place the stripped wires crosswise on top of each other approximately in the middle of the exposed area and begin to twist. One wire goes around another wire, and wrap the second wire around the first in the same way.

Bandage twist

Stranded wires can be connected together using the bandage twist method. In this case, the connected conductors are stripped to the same length and applied parallel to each other. In this position, they are fixed with a third wire, which is tightly wound onto the bare surface of the connected conductors.

Please note that using such twisting you can connect hard stranded wires, but you must use a soft (flexible) wire as a fixing wire. The more tightly you wind the fixing wire, the more reliable the contact connection will be.

More than two conductors can be connected using bandage twisting.

Solid wires

All the above-discussed twisting methods stranded wires Can also be used for single-core. But it is best in this case to use a parallel connection.

Remember the most important thing: before connecting single-core wires, the insulating layer on them should be stripped only along the conductor at an angle. This is especially true for aluminum conductors. If you run a knife at a 90 degree angle around the conductor, the insulation will, of course, be removed. But in further work, with the slightest movements at the place of the cut, the conductor will eventually bend and, ultimately, the core will break.

Strip the insulating layer by 3-4 cm on the wires to be connected. Place the wires on top of each other at an angle of 45 degrees, but not in the area of the bare wires, but 1.5-2 cm above the place where the insulation was cut. Hold this place firmly with your left hand, and with your right hand begin to twist both wires. First, they will be twisted together with the insulating layer, then the connection of purely bare conductors will begin.

No matter how strong your hands are, be sure to finish twisting with pliers at the end, especially when it comes to aluminum wires.

Another important advice! After you make the twist, do not rush to insulate it. Let the electrical circuit work for several hours, then turn off the input circuit breaker for the apartment and check the temperature at the place where it is twisted. If the node is hot, it means that the contact connection is unreliable and it is better to redo it. If no heating is detected, then the twisting is done well and can insulate it.

If necessary a large number of twists, you can use a screwdriver with a homemade device, as shown in the video below:

Methods for insulating twists

Twisting the wires is half the battle; it is very important to properly insulate this place. There are three ways to insulate a completed electrical assembly: using insulating tape, heat-shrinkable tubing, and PPE caps. Let's look at each of them in more detail.

Insulating tape

Insulating tape – special material, the main purpose of which is to isolate the connection point electrical cables and wires. Whatever appears modern technologies, you can hardly meet an electrician who doesn’t have a roll of electrical tape in his pocket. This is the most common and inexpensive insulating material.

There are many varieties of it. Tapes are made from mica and fiberglass, polyester and epoxy films, acetate fabric and paper. To insulate twists in a household electrical network, we recommend using PVC tape (it is based on polyvinyl chloride). To make it, take a polyvinyl chloride film and apply glue on top. The quality of the insulating tape itself, and, accordingly, the reliability of the insulated joint depends on the quality of these two components.

The best insulating tape is considered to be the one made using rubber-based glue and PVC film class A. This material is distinguished by such positive qualities, How:

High adhesion (adhesion of dissimilar surfaces).
Increased elasticity (excellent stretch and adhesiveness).

So be sure to keep this in mind when purchasing duct tape.

The insulating tape should be wrapped around the twisted section in at least two layers. Start winding 2-3 cm above the bare twist, the tape should be placed on top of the wire insulation. This will allow you to achieve maximum tightness and insulating reliability, and will protect the contact connection from moisture. Next, wind it a little at an angle, moving towards the end of the twist. Having reached the end, bend the electrical tape around the tip of the twist and continue winding now in reverse side. Having reached the place where you started winding, cut the insulating tape with a knife. For efficiency, you can repeat the same thing again and make four layers of insulation.

Thermal tube

Heat-shrinkable tube (abbreviated as HERE) is made of thermopolymer materials that have the property of being exposed to hot air, water or elevated temperature change your geometric shape and dimensions (shrink or expand).

The main advantage of thermal tubes is that they can be attached to objects with a complex profile, which is exactly what twisted wires have. Heat-shrinkable tubing provides excellent electrical insulation and protects against mechanical damage. The tubes come in different diameters. The material from which they are made does not support combustion and is non-toxic.

Industrial hair dryers are used to apply heat to the tubes. This tool is not cheap and it is not economically profitable to buy it just to insulate the spliced wires. Therefore in living conditions often use an ordinary hair dryer or lighter.

It is important to remember that with this insulation method, the heat-shrinkable tube must be placed on one wire to be connected in advance (before twisting).

Cut the tube with a margin; when it is put on the bare area, it should extend onto the insulating layer of the conductor by at least 1 cm.

When the twisted connection of the electrical wires is completed, pull the tube over this place. Direct the heat jet of a hairdryer or the flame of a lighter at it; under the influence of hot air, the tube will instantly decrease in size and tightly seal the insulated area. Reliable, fast and inexpensive way.

Keep in mind that the connected wires, which are insulated with a heat pipe, can be used for laying in the ground or when immersed in water. The insulating material It is recommended for use outdoors, in baths and bathrooms, as it will reliably protect the twisting area from moisture.

How to choose to use heat shrink tube shown in this video:

PPE caps

When installing wiring in an apartment or house, you can use PPE caps (connecting insulating clamp) to insulate the connection points.

In this case, it is enough to make only high-quality twisting, without soldering. The tip must be cut off and put on with PPE force; the crimp springs inside the cap will expand and tightly grasp the unit being connected. To better fit the connection surface, rotate the cap clockwise.

Now you know how to twist wires correctly and what material is best to choose for insulating the connection. From the article it is clear that to perform twisting it is not at all necessary to be a professional electrician; such work can be done by anyone who knows how to hold pliers in their hands. Just don’t forget that twisting is only important stage, which must be completed by welding or soldering.

How to connect a single-core and stranded wire so that this does not lead to problems in the future, and the contact connection serves us for many years? And in general, how to make connections correctly various types wires?

We will try to answer all these questions in our article, and we will also analyze what such rules are associated with and what dangers are hidden behind an incorrect connection.

First of all, let's look at what the requirements for high-quality contact connections are related to. It is not without reason that clause 2.1.21 of the PUE separately stipulates methods for connecting wires, and allows only screw or bolt clamps, crimping, welding or soldering.

This is due primarily to the fact that these types of connections can provide proper level durability and reliability of the connection. After all, any electrician will tell you that more than 90% of all damage occurs at contact connections, and that is why so much attention is paid to them.
After all, what is a poor-quality contact connection is a connection that has a high contact resistance. And since we have resistance, this means heating.

As we remember from the physics course, any conductor in a heated state has greater resistance than a conductor with a lower temperature. Therefore, an avalanche-like process results. A poor-quality contact connection causes the conductor to heat up and its resistance increases even more. As a result, it heats up even more until it reaches the point where it simply melts.
As a result, our main task is to ensure minimum resistance between the two conductors being connected. This is achieved by ensuring the proper area of contact between the two conductors, as well as by ensuring the maximum possible contact between them.
Let's immediately look at why we will not consider the question of how to twist single-core wires or their multi-core counterparts. After all, when the right approach, and by twisting it is possible to ensure a sufficient area of contact and compression of the conductors with each other.

The fact is that in any case, the contact connection will be subject to temperature influences. That is, it will heat up and cool down. And as we know, heating leads to expansion of materials, and cooling, accordingly, to contraction. As a result, our contact connection, which is not fixed by any third element, can quickly become of insufficient quality.

Note! Surely each of you can give dozens and hundreds of examples where twisting has lasted for decades, and even now looks better than screw or bolt connections. But, as they say, exceptions to the rule only confirm the rule itself. According to statistics, twisted joints are damaged much more often than other types of joints.

Correct connection of conductors

Now we can talk about how to correctly connect a single-core and stranded wire, two single-core or two stranded wires. And also, which type of connection for each of these types will be optimal, and which should be used only with certain restrictions.

Connection using the compression method

By compression method, PUE means screw or bolt connection of conductors. The same type of connection includes the now popular Wago terminals, which use the compression method through the use of springs or special mechanisms.

On this moment The compression method is one of the most popular joining methods. After all, the price of terminals based on this method is one of the lowest. The installation process is simple and does not require additional equipment, and the method itself is quite reliable.

For wires of small cross-section, the screw connection method is mainly used - or the compression method using a special mechanism. The essence of the screw method is that two conductors are installed in a brass tube, which are then each clamped with its own screw.
This method is well suited for connecting two single-core copper conductors. If aluminum is used, then this material is softer, and when clamping it with a screw, you can either critically reduce its cross-section or completely crush it. Therefore for aluminum wires This method is not recommended or should be used with extreme caution.

In the photo - a tip for a stranded wire

Using a screw clamp to connect multi-core wires is also associated with the possibility of breaking individual wires that make up the conductor in whole or in part during the process of tightening the screw. To protect the wires from mechanical influences, special tips should be used.
Using special lugs, stranded wires can be connected both to each other and between single-core wires using screw terminals.

There are screw terminals with a special clamping pad, which provides clamping over the entire cross-section of the brass tube. In this case, the use of special lugs for stranded wires is not necessary.

As for Wago terminals and the like. There is still debate among electricians about their reliability and durability. Some argue that the use of springs in terminals is not the best option, others that it is very convenient and the springs are quite reliable.

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

About the distribution box

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

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

Distribution boxes are classified according to the type of fastening. So, there are boxes for external 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 attached directly to the wall.

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

What are distribution boxes for?

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

The power system can be repaired in a matter of hours. All connections are accessible, you can easily find the area where the wires have burned out. If the cable was laid in special channels (corrugated tube, for example), then the failed cable can be replaced in an hour;
Connections can be inspected at any time. As a rule, wiring problems occur at the connection points. If the socket or switch does not work, but there is voltage in the network, first check the quality of the connection in the junction box;
is created highest level fire safety. It is believed that dangerous places- these 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 ways, however, if executed correctly, all options will ensure reliable electrical wiring.

Method No. 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 number 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 electrical parameters twists. 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 the 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 terminal blocks are placed in a plastic housing. There are open and closed type. 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 most best view connector. The wire, stripped of insulation, is inserted into the terminal and a small lever is clamped. At this point the connection is considered complete. And if you need to reconnect, add contacts, lift the lever and pull out the wire. The pads can be operated at low current (up to 24 A - with a cross-section of 1.5 sq. mm) and at high current (32 A - with a conductor cross-section of 2.5 sq. mm). If wires are connected through which a current higher than that specified will flow, then a different type of connection must be used.

Method number 6. Crimping

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

Method No. 7. Bolted connection

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

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

There are several advantages of bolted connection of conductors:

- ease of work;

- low cost;

- the ability to connect conductors made of different metals (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;

First of all, you must understand that different conditions may be applied Various types connections. And their choice depends on the specific task at hand.

For example, it is much more convenient to connect small-section wires up to 2.5 mm2 in a compact junction box with terminal blocks or clamps. But if we are talking about a strob or cable channel, then the sleeves come first here.

Let's consider the three most simple and at the same time reliable types of connections.

Let's start with the connection type PPE. It stands for:

WITH unifying

AND insulating

Z pressure

It looks like a simple cap. Comes in different colors.

Moreover, each color means that it belongs to specific sections of the cores.

The cores are inserted into this cap and twisted together.

How to do it correctly, first twist the wires and then put on the cap or twist them directly with the PPE itself, is discussed in detail in the article “.”

As a result, thanks to PPE, you get a good old twist, only immediately protected and insulated.

On top of that, it has a spring-loaded contact that prevents it from coming loose.

In addition, this process can be slightly automated by using an attachment for PPE for a screwdriver. This is also discussed in the above article.

The next type is Wago terminal blocks. They also come different sizes, and under different quantities connected wires - two, three, five, eight.

They can connect both monocores and stranded wires together.

Moreover, this can be implemented as in different types Vago, and in one single thing.

For stranded ones, the clamp must have a latch-flag, which, when open, easily allows you to insert the wire and clamp it inside after latching.

According to the manufacturer, these terminal blocks in home wiring can easily withstand loads of up to 24A (lights, sockets).

There are some compact specimens also available for 32A-41A.

Here are the most popular types of Wago clamps, their markings, characteristics and what cross-section they are designed for:

Series 2273 Series 221-222 Series 243 Series 773 Series 224

There is also industrial series for cable cross-sections up to 95mm2. Their terminals are really large, but the principle of operation is almost the same as that of small ones.

When you measure the load on such terminals, with a current value of more than 200A, and at the same time you see that nothing is burning or heating, many doubts about Wago products disappear.

If you have original Vago clamps, and not a Chinese counterfeit, and the line is protected by a circuit breaker with a correctly selected setting, then this type of connection can rightfully be called the simplest, most modern and convenient to install.

Violate any of the above conditions and the result will be quite natural.

Therefore, there is no need to install wago at 24A and at the same time protect such wiring with a 25A automatic. In this case, the contact will burn out if overloaded.

Always choose the right terminal blocks for your car.

As a rule, you already have automatic machines, and they primarily protect the electrical wiring, and not the load and the end consumer.

There is also enough old look connections, such as terminal blocks. ZVI – insulated screw clamp.

In appearance, this is a very simple screw connection of wires to each other. Again, it comes in different sections and different shapes.

Here they are specifications(current, cross-section, dimensions, screw torque):

However, ZVI has a number significant shortcomings, because of which it cannot be called the most successful and reliable connection.

Basically, you can only connect two wires to each other in this way. Unless, of course, you specifically choose large pads and shove several wires there. What to do is not recommended.

This screw connection works well for monocores, but not for stranded flexible wires.

For flexible wires, you will have to press them with NShVI lugs and incur additional costs.

You can find videos online where, as an experiment, transition resistances on different types of connections are measured with a microohmmeter.

Surprisingly, the lowest value is obtained for screw terminals.

But we should not forget that this experiment refers to “fresh contacts”. Try making the same measurements after a year or two of intensive use. The results will be completely different.

Copper and aluminum connection

Often a situation arises when it is necessary to connect a copper conductor to an aluminum one. Because Chemical properties Copper and aluminum are different, then direct contact between them, with access to oxygen, leads to oxidation. Often even copper contacts on circuit breakers susceptible to this phenomenon.

An oxide film forms, resistance increases, and heating occurs. Here we recommend using 3 options to avoid this:

They remove direct contact between aluminum and copper. The connection occurs through steel.

The contacts are separated from each other in separate cells, plus the paste prevents the access of air and prevents the oxidation process from developing.

The third simple way to connect conductors is crimping with sleeves.

GML sleeves are most often used for joining copper wires. Deciphered as:

G Ilsa

M single

L narrowed

For connecting pure aluminum - GA (aluminum sleeve):

To switch from copper to aluminum, special adapters GAM:

What is the crimping method? Everything is quite simple. Take two conductors and strip them to the required distance.

After this, on each side of the sleeve, the conductors are inserted inside, and the whole thing is crimped with press pliers.

Despite its obvious simplicity, there are several rules and nuances in this procedure, if not followed, you can easily ruin a seemingly reliable contact. Read about these mistakes and rules on how to avoid them in the articles “” and “”.

To work with conductors of large sections 35mm2-240mm2, a hydraulic press is used.

Up to cross-sections of 35mm2, you can also use a mechanical one with a large span of handles.

The sleeve must be crimped two to four times, depending on the cross-section of the wire and the length of the tube.

The most important thing in this work is to choose the correct sleeve size.

For example, when connecting a monocore, the sleeve is usually taken to a smaller cross-sectional size.

And in this way you can connect several conductors at one point at the same time. In this case, only one sleeve will be used.

The main thing is to completely fill its internal space. If you are crimping three conductors at the same time, and you still have voids inside, then you need to “fill” this free space with additional pieces of the same wire, or with conductors of a smaller cross-section.

Crimping with sleeves is one of the most versatile and reliable connections, especially when it is necessary to extend the cable, including the input cable.

In this case, the insulation turns out to be almost equivalent to the main one, when also using the outer tube HERE as a casing.

Of course, you won’t use either PPE or Wago for these purposes, but GML cartridges are just the thing! At the same time, everything comes out compact and can be easily reduced, either in a groove or in a cable channel.

Welding and soldering

In addition to all the above connection methods, there are two more types that experienced electricians rightfully consider the most reliable.

And even with its help it is not always possible to connect an aluminum monocore wire with a flexible copper stranded one. In addition, you are forever tied to an outlet or extension cord.

What if there is no voltage or generator nearby?

At the same time, on the contrary, 90% of electrical installers have elementary press pliers. It is not necessary to purchase the most expensive and sophisticated ones for this.

For example, batteries. It’s convenient, of course, just walk and press a button.

The Chinese counterparts also cope well with their task of crimping. Moreover, the entire process takes no more than 1 minute.

One of the fastest and at the same time most unreliable methods of splicing wires is twisting the cores. It is popular because it does not require special devices, and only insulation tape to close the connection. You don’t need to have special skills, just know the most common types of twists. However, this method is not without drawbacks.

Why twisting - the main advantages

If you need to connect two copper wires together, you can solder them. But not everyone has this useful skill, and a soldering iron may not be at hand, for example, if the cable of a power tool or a wire in a junction box in the countryside breaks. Therefore, such a property of copper and aluminum cores as flexibility is very convenient - they can simply be folded together and twisted into neat turns. In this case, you won’t even need pliers if the metal cores of the wires have a small diameter. This applies not only to television cable, antenna, telephone and many others, including computer ones.

Another advantage is enough high quality solderless connections. If the wire serves to transmit a signal, interference due to twisting usually does not appear, and if it does occur, it is in very rare cases. It is very important that this connection saves time and sometimes money. In particular, there is no need to wait for the soldering iron to warm up or equip a special welding inverter for wires, there is no need to tin every wire.

If the cores are varnished and do not provide contact, they can simply be scorched with a match or lighter.

When scorched, very thin veins easily burn or become brittle, which can already be considered a disadvantage.

What you need to know - the nuances of using twists and their disadvantages

So we've mentioned some of the challenges of working with very thin, varnished copper cores. Without stripping, they will not make contact, but simply scorch open flame- means burning the wire. However, it is not always possible to easily deal with thick conductors using conventional splicing. For example, aluminum is quite brittle and too many turns leads to microcracks, which cause the twisted ends to simply break. Approximately the same thing happens in severe frost with a copper core - when the turns are strongly tightened, they burst.

There are also directly opposite nuances, in particular those related to insufficiently tight twisting of the ends of the wire. Each time, after connecting the cores of two cables by twisting, you need to connect the power without insulation and after 30-40 minutes check whether the core is heating up. The fact is that when the conductors do not touch tightly, increased resistance occurs and the junction begins to heat up quickly, which can lead to burnout of the splice of the wires. It should be taken into account that due to temperature changes, the twisting of the wires weakens over time and still begins to heat up.

To connect the bare ends of the wire, just twist them with your fingers, but it is recommended to use pliers to create good, tight turns.

It is highly undesirable to connect conductors made of two different metals, for example, aluminum and copper, but if there is no other option, you should use a special terminal, caps or blocks. We also avoid splicing a single-core wire with a stranded one, since they have different resistances, and with the same diameter they are designed for different load. If you still have to resort to such a connection, calculate the peak power of the current that will pass through the conductors at maximum load. It should be within the acceptable range for the weaker wire.

Existing types of twists - a list of commonly used ones

There are dozens of schemes for interweaving single-conductor and multi-core cables together. At the same time, it is extremely important to know that you should always connect wires of the same type, or use special electrical distribution boxes with terminals or screw clamps. These same devices easily combine cores made of different metals. As for twists, there are parallel, serial and branches. The difference between them is the location of the conductors relative to each other. In the first case, the ends are placed side by side, in the second they are brought together, and in the last option we connect the conductor perpendicular to the exposed area.

As for the splicing method, there can be quite a lot of room for action. So, for example, multi-core cables can be pre-twisted at the ends and you will twist the wires correctly as if you had single-core cores in your hands. But it is still better to splice in a sequential manner, first separating the wires at both ends and then weaving them in with oppositely directed turns. Wires with one core each can be twisted in a simple way, groove or bandage. We will examine each of them in more detail.

We twist a stranded wire - the best option

As already mentioned, if there are no terminals, we use twisting, but the main condition for any multi-core cable– maximum contact of all conductors at the connection point. Therefore, having exposed the ends, we twist each of them at the base, a quarter of the length from the insulation, and then spread them apart with a whisk. We do this with each wire, usually you need to make 2 twists of electrical wires to get plus and minus (or zero and phase), less often 3 - if there is another phase or grounding.

For a serial connection, we carefully bring the bundles together in a counter motion so that the rims fit into one another and the wires intersect, even at different arbitrary angles. Next, we begin to twist the wires of one end away from ourselves, and the other towards ourselves, if you look at the cables from the side. In general, they will curl in the same direction, clockwise, when looking at each rim from the joining point.

The parallel connection of electrical wires is performed in almost the same way, only the ends with separated bundles of wires are brought to each other at a slight angle from the side until they intersect. After obtaining the desired contact, we simply weave all the strands into one thick braid. Then, of course, it is advisable to fill the resulting twist with tin, having previously tinned it, but if this is not possible, you can wind the insulation, always in at least 2 layers. For this purpose, special tubes are also used, placed on the wire before connecting.

We connect wires with one core - effective ways

The simple parallel option is the fastest. All that is needed is to connect two wires that need to be twisted together at a certain angle, and then twist them in even turns from the point of intersection. To make a serial connection, you need to slightly bend the bare ends of the wires, bring them together in a counter motion so that they intersect. Then wrap each one around the base of the other, one away from you, and the other towards you, if you look at the cable from the side.

Parallel fastening with a groove is made by curling one conductor around the other at two points - at the base of the stripped core, closer to the insulation, and near its end, which is previously slightly bent. This method gives a fairly smooth and durable installation, essentially consisting of two twists. The serial connection is carried out by mutual braiding of wires bent at the ends with a pass small area. Again, you will get two twists near the insulation itself.

A bandage is made in cases where the wires are too thick and difficult to twist together. In such a situation, the conductors are stripped of insulation and bent 90 degrees at the ends, after which they are connected to each other in parallel or in series. Then a thinner core is taken, also necessarily from a wire with one core, and wrapped in even turns around the mounted areas. Then insulation is applied.

The connection of three wires is no different, you just need to add a third core to one of the first two in a parallel way, and then connect them together using any of the options listed above. The same applies to the fork. The only difference in connecting the side wire to the bare area is that only it will be wrapped in turns, and the main wire will serve as the base. All of the above methods are suitable, including a bandage in a situation where the core of the cable being connected has a too large diameter.