Connection with contact clamps. Connection and termination of wires Bandage connection of wires

We will not prove to you that the twisting of wires is good way connections. Yes, it can be done with high quality and insulated. It is also great as a temporary option. But according to the rules for electrical installations (PUE), in order to connect a wire or cable, ordinary twists are not recommended. Nevertheless, we will talk about it, and very detailed. Firstly, because, contrary to the PUE, most of the connections are still made by this old "grandfather" method. Secondly, because the correct twist is the main step in the most reliable ways to connect wires - welding and soldering.

Why do you need a good twist?

Imagine that two wires to be connected are twisted together just as if. Those who are familiar with electrical engineering know that a contact resistance arises at the point of contact between 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 atmospheric oxygen, as a result of which the surface of the conductor is covered with an oxide film, which has a decent value of resistivity.

example of poor-quality twisting: the twisting point heats up, 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 heat. As a result, the place of twisting may heat up so that the electrical wiring will ignite. Surely everyone had to hear the phrase in their life that the fire occurred due to a malfunction in the electrical network.

To prevent this from happening, the contact connection of the wires must be as strong, reliable and safe as possible. That is, the twisting must be performed with such high quality that the contact resistance is stable and does not change over time.

Preparing wires for twisting

Remember! Never do twisting under tension, even if you have a tool with insulated handles and dielectric gloves. To start, de-energize workplace by turning off the introductory machine for an apartment or house.

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

1. Strip the wires to be connected from insulation, while preventing damage metal surfaces conductors.
2. Moisten a clean cloth with white spirit or acetone and wipe the exposed areas of the wires from dirt.
3. Now, using sandpaper, clean the veins to a metallic sheen.

stranded wires

Stranding stranded electrical wires can be done in different ways.

Parallel twist

The simplest method is parallel stranding, when both stripped wires are crisscrossed over each other at the stripping point and twisted at the same time. Such a connection gives reliable contact, but it will not tolerate the applied force to break and vibration.

This method is best used for copper wires, when one of them is monolithic, and the other is stranded. A monolithic wire must be stripped of insulation a little more than a stranded one. 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.

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

Sequential stranding

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

Fold the stripped strands crosswise on top of each other approximately in the middle of the bare area and start twisting. One wire goes around the other wire, just wrap the second wire around the first.

Bandage twist

Stranded wires can be connected to each other by the method of bandage twisting. In this case, the wires to be connected 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 cores.

Please note that with the help of such a twist, you can connect hard stranded wires, but you must use a soft (flexible) wire as a fixing wire. The tighter you make the winding of the fixing wire, the more reliable the contact connection will be.

More than two conductors can be connected using a bandage twist.

Solid wires

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

Remember the most important thing, before connecting single-core wires, insulating layer they should only be stripped along the conductor at an angle. This is especially true for aluminum conductors. If you run the knife at a 90 degree angle around the conductor, the insulation will of course come off. But in further work at the slightest movement at the place of the incision, the conductor will break over time and, ultimately, the core will break.

Strip the insulating layer on the connected wires by 3-4 cm. Lay the wires on top of each other at an angle of 45 degrees, but not in the place of the bare wires, but 1.5-2 cm higher from the place where the insulation was cut. Hold this place firmly with your left hand, start twisting both wires with your right hand. First, they will twist together with the insulating layer, then the connection of purely bare cores will already go.

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

Another important advice! After you make a twist, do not rush to isolate it. Give electrical circuit work for several hours, then turn off the introductory machine to the apartment and check the temperature at the place of twisting. If the node is hot, then the contact connection turned out to be unreliable and it is better to redo it. If no heating is detected, then the twisting is done with high quality, it can be insulated.

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

Ways to isolate twists

Twisting the wires is half the battle, it is very important to insulate this place with high quality. There are three ways to insulate the made electrical assembly: using insulating tape, heat-shrinkable tubing and PPE caps. Let's consider each of them in more detail.

Insulating tape

Insulating tape is a special material, the main purpose of which is to isolate the junction electrical cables and wires. Whatever appears modern technologies, you can hardly meet an electrician who would not 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 on the basis of mica and fiberglass, polyester and epoxy films, acetate fabric and paper. To isolate strands in a household electrical network, we recommend using pvc tape(it is based on polyvinyl chloride). For its manufacture, a polyvinyl chloride film is taken and glue is applied on top. The quality of the insulating tape itself depends on the quality of these two components, and, accordingly, the reliability of the insulated junction.

Electrical tape is considered the best, for the manufacture of which rubber-based glue is used and pvc film class A. This material is characterized by such positive qualities, as:

1. High adhesion (adhesion of dissimilar surfaces).
2. Increased elasticity (excellent stretches and glues).

So be sure to consider this when buying electrical tape.

Insulating tape should be wound around the twisted section in at least two layers. Start winding 2-3 cm above the bare twist, the tape should be applied over the wire insulation. This will achieve maximum tightness and insulating reliability, protect the contact connection from moisture. Then wind 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 the winding began, cut the insulating tape with a knife. For efficiency, you can repeat the same thing again and make four layers of insulation.

thermotube

A heat-shrinkable tube (abbreviated as HERE) is made of thermopolymer materials that tend to change their shape under the influence of hot air, water or elevated temperature. geometric shape and dimensions (shrink or expand).

The main advantage of thermotubes is that they can be put on objects with a complex profile, which is exactly what the twisted wires have. Heat shrink tubing provides excellent electrical insulation and protects against mechanical damage. Tubes let out different diameter. The material from which they are made does not support combustion and is not toxic.

For thermal impact on the tubes used industrial hair dryers. This tool is not cheap and buying it just to insulate the splicing of wires is not economically viable. Therefore, in living conditions often use an ordinary hair dryer or a lighter.

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

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

When the connection of the electrical wires with a twist is completed, pull the tube over this place. Direct the heat jet of a hair dryer or the flame of a lighter at it, under the influence of hot air, the tube will instantly decrease in size and tightly compress 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 recommended for use outdoors, in baths and bathrooms, as it will reliably protect the place of twisting from moisture.

How to pick up to use heat shrink tubing is shown in this video:

PPE caps

When installing wiring in an apartment or house, PPE caps (connecting insulating clamp) can be used as insulation for 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 PPE with force, the compression springs inside the cap will move apart and tightly wrap around the unit to be connected. For a better fit on the connection surface, turn the cap clockwise.

Now you know how to twist the wires correctly, what material is better to choose for insulating the junction. From the article it is clear that in order to perform twisting it is not at all necessary to be professional electrician, such work is within the power of anyone who knows how to hold pliers in their hands. Just do not forget that twisting is only milestone to be completed by welding or soldering.

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Work on the connection and repair of overhead lines is usually carried out immediately after rolling or even during rolling of the wire before lifting it to the supports.
The connection of overhead lines wires can be performed by twisting, crimping or crimping in oval connectors, thermite welding and other methods.
The ends of aluminum wires are cleaned of dirt and factory grease with a rag soaked in gasoline and coated with technical petroleum jelly. At a distance of 20 ... 25 mm from the end, a wire bandage is applied to the wire and the wire is trimmed (with a hacksaw or MI-148A cable cutter, the end of the wire is cut strictly perpendicular to its surface). After that, a second bandage is applied to the wire at a distance slightly exceeding the length of the connector. The first bandage is removed, the layers of wires are untwisted and each of them is cleaned to a shine with a steel brush under a layer of petroleum jelly. Then metal filings and petroleum jelly are removed with a clean dry rag, the wires are again twisted into layers and the first bandage is restored near the end of the wire. Preparation for connecting steel and copper wires comes down to cleaning with a rag soaked in gasoline and lubricating with petroleum jelly.
To connect the wires of the overhead line, special connectors are used. The oval connector brand CO AS (oval connector for steel-aluminum wires) is a seamless metal sleeve, the size of which depends on the cross section of the connected wires.

Rice. 1. Connecting wires with an oval connector

Copper wires are connected in copper connectors, aluminum and steel-aluminum - in aluminum, and steel stranded - in steel or copper connectors. In preparation for the connection, the oval connector is cleaned of dirt, washed in gasoline, wiped dry with a clean rag and lubricated with petroleum jelly. If there are signs of corrosion on the connector (or on the wire), they are removed with a steel brush, and the cleaned places are covered with petroleum jelly.
The connection of aluminum and steel-aluminum wires with a cross section of up to 95 mm2 by twisting the oval connector (Fig. 1) is carried out as follows. The prepared ends of the wires 1 are inserted into the connector 2 as shown in the figure, then it is placed in the MI-189A or MI-190A device and fixed with one end in a fixed clamp, and with the other - in swivel head fixtures.

Rice. 2. Connecting wires by connector and thermite welding
Using a lever, the head with the clamped end of the connector is turned 4 ... 4.5 turns, after which the finished connection is released from the clamps and removed from the fixture.
Steel wires are connected with oval connectors of the SOS type using the same technology as aluminum wires in SOAC connectors, but in this case the connector is twisted by only 2 ... 2.5 turns. In addition, after mounting the connection, the steel body of the connector is coated with a layer of anti-corrosion paint or ZES grease.

Rice. 3. Pliers for thermite welding of wires
AT last years the combined method of connecting wires is widely used (Fig. 2): the connection using oval connectors is supplemented by thermite welding. To make such a connection, first mount the wire connection in the oval connector in the manner described above, but extend the ends of the wires from the connector so long (about 0.75% of the connector length) that they can then be welded at point C. After that, thermite welding of the wire ends is performed in a thermite cartridge.
For thermite welding of overhead lines, special welding tongs(Fig. 3). Handles 6 are spread apart and fixed with a special stopper or strap 7. Wires 4 prepared for welding are inserted into the thermite cartridge 2, each wire is fixed in clamping devices 3 so that the cut of the mold is on top. The thermite cartridge is lit in the place indicated by paint or a label, lowered protective screen 1 and release the stopper. The burning thermite mass melts the insert and the ends of the wires, and as the wires melt, their ends located in the mold move towards each other, since the spring 5 brings the handles of the tongs closer together. After the end of welding, when the molten metal has solidified, the wires are released from the clamping devices, unbent, the mold is removed and the place of welding is cleaned. The loop formed by the welded ends does not make it possible to pull the wire along the rolling rollers, therefore thermite welding is carried out from the mounting towers after the wire has been raised to the supports, stretched and fixed.

Rice. 5. Joining steel wires by welding

Rice. 4. Using two connectors and thermite welding
It is much more convenient to perform thermite welding in a different way (Fig. 4). Wires 1 are connected to each other using two oval connectors 2 and an additional piece of wire 3. Oval connectors are freely put on both connected ends and thermite welding of wires is performed at point 4. After that, an additional wire is inserted into both connectors and the connection is made by crimping or twisting. Thermite welding provides reliable electrical contact, and mechanical tension is transmitted through the connectors and an additional piece of wire. Such a connection can be made on the ground, as it passes freely through the sheeting rollers.

Rice. 6. Bandage connection of steel single-wire wires

Steel single-wire wires can be welded by conventional electric overlap welding on both sides (Fig. 5), followed by coating the junction with weather-resistant paint. Instead of welding, it is allowed to use a bandage made of galvanized wire with a diameter of 1.5 mm (Fig. 6). To make such a connection, the ends of the wires are bent at a right angle in a section with a length of at least two wire diameters. On one of the wires tightly, turn to turn, a wire bandage is wound over a section 15 mm long, then a second wire is applied, a common bandage is made to the bent end and another 15 mm bandage is applied on the second wire. The length of the common bandage that captures both wires depends on their diameter: with a diameter of 4 mm - at least 40 mm, with 5 mm - at least 50 mm and with a diameter of 6 mm - at least 80 mm. After applying the bandage, the connection is soldered to create a reliable contact (it is not allowed to use materials that are harmful to the wires for soldering).
Connecting wires from different metals or different sections are allowed only on a support, since it should not experience mechanical stress. It is not allowed to connect wires at overhead line crossing points over roads, overpasses, etc.
During the rolling of the wires, they are inspected for possible damage. Wires are considered damaged if they have dents more than half their diameter deep or are completely broken. If the number of damaged or broken wires does not exceed 10% (for aluminum) or 20% (for steel-aluminum wires), the wire is repaired at the point of damage.
In case of a simple breakage of the wire, it is straightened, laid in a coil of wire and a wire bandage up to 25 wire diameters long is applied to the damaged area, preventing further untwisting of the broken wire. If 2 ... 3 wires are broken in several places, they are cut out at the same length, at damaged area weave the missing wires and fix their ends with wire bandages. To repair wires, a repair sleeve is used - a regular oval connector, taken one size below the cross section of the wire being repaired (for example, to repair wires with a cross section of 50 mm2, a connector is required for connecting wires with a cross section of 35 mm2). The connector is cut along, its edges are parted so that its body can be put on the wire. After that, the connector is pushed onto the damage site so that it is approximately in the middle of the coupling. One edge of the coupling is brought to the other, wire bandages are applied to the wire near the ends of the coupling, preventing its displacement, tightly envelop the coupling around wire light hammer blows and squeeze it in the usual way pressing tongs or hand press. The distance between two wire bandages or repair sleeves must be at least 15 m.

Laying electrical wiring in the house involves connecting wires, from the main network you will need to make branches necessary to provide power to electrical appliances.

How to make a wiring connection

The connection of wires is required everywhere in the premises, in the car, devices and mechanisms, wherever there are wires. Today, the following methods are used:

• twist;
• Welding;
• Soldering;
• With the help of special blocks, terminal blocks;
• Using self-clamping terminal blocks;
• With PPE caps.

What you need to know about twist

Look carefully at the photo of the twisting of wires, you will see that it can be done in different ways. You will need to prepare tools: a knife to strip the insulation, pliers to make the connection reliable, and you will also need electrical tape to insulate the twist.

Method - twisting the wiring with protected ends

Bare the wires by at least 5 cm, cross the ends that are not protected by insulation, clamp the resulting crosshair with pliers and twist them together by performing a rotational movement.

A common way is twisting with a groove

To get started, check out the sequence of steps on how to make a twist of wires with your own hands. Bend the ends of the wire into small hooks, hook them together, wrap one wire around the other.

Insulate the resulting twist to ensure human safety, contact reliability, prevent current leakage and short circuit.

Professionals say that these types of wire twisting can be made more durable by using the following recommendations:

Twisted contacts are additionally connected by soldering or welding, as a result, the contact acquires maximum reliability, it is almost impossible to break it. It is preferable to use soldering when both cores of the connection have a large cross section.

WAGO terminals greatly facilitate the connection, making it more efficient, they are needed when you have to figure out how to twist copper wires with aluminium. The whole procedure will take place quickly enough, while the "wags" allow you to connect wires that have different section, the contact will be reliable and durable.

If the home master is faced with the task of connecting the wires in an electrical outlet or lamp, use the WAGO terminal blocks.

Thanks to PPE clamps, the reliability of the connection increases significantly, it becomes as safe as possible. These products have low price so they are available at any electrical supply store.

Wires twisted together should not be immediately closed with a junction box. It is better to observe how the power grid works for several hours, after which it is recommended to check the temperature at the attachment point. If the connection is very hot, you need to do everything again: most likely, the contacts turned out to be unreliable.

The twist itself is not waterproof, so it’s better to take a box to connect the cores inside the wall, if without it, then the twist wires will need to be insulated with cambric.

It remains for you to determine for yourself which method of twisting is best, and consider methods for isolating knots.

What the DIYer Should Know About Soldering and Welding

Soldering is considered simply an improvement in twisting, first the wires are twisted and then they are soldered using a soldering iron with solder. Advantages of soldering:

• Increasing the strength of the twist;
• Reduced resistance, which means the twist point will not heat up.

Copper stranded wiring can be easily soldered, but this method is not suitable for all wires, the exception is the twisting of aluminum wires. Since soldering is fragile, it must not be done carelessly, otherwise a poor-quality connection will result.

Welding is another way to improve stranding, it increases reliability, but is also not suitable for aluminum wires. It is used for multi-core copper cables with a large cross section, welding reliability is considered higher compared to soldering.

When using welding, it is impossible to exclude the possibility of weakening the twist, under the influence of high temperatures performance characteristics metal can change.

Isolation methods

Wire insulation is performed using various types of electrical tape, it is necessary to isolate the place of twist and cut insulated wires, equal to at least 2 or 3 cm. Then it will be possible to make high-quality insulation that protects against unwanted ingress of moisture on the contacts, and special thermal tubes are additionally used for this purpose.

Insulation with a thermotube

A tube with the desired length is put on one core before twisting.

Twisting is performed, after which the thermotube is shifted to the junction of the contacts.

It is necessary that the tube fit as tightly as possible to the wiring, so it is heated a little with a lighter. Under influence high temperature the thermotube will shrink, and it will be possible to ensure a tight grip on the wiring.

The advantages of all kinds of twists are the simplicity of their execution, despite the minimal equipment, they have proven to be quite reliable connections.

When high-quality insulation is made, for which good electrical tape was used, the life of the twist will be quite long. Such a connection is convenient in operation: it is detachable, which means that if necessary, the wires can simply be twisted again.

Twisting is used in loose electrical wiring that sags, this method was adopted by motorists, in the car the wiring is subjected to constant vibration.

Among the disadvantages of twisting, the following should be noted:

It is not possible to connect wires with different cross-sections; in such a connection, as a rule, there is a very high resistance, which causes constant heating of the wires and melting of their insulating layer.

It is difficult to join stranded cables with a twist, which are soft and with any tension the connection can break.

When there are several insulated wires in the wiring, due to the fact that each core is insulated individually, the total thickness can be very large.

Twisting is not suitable when it is necessary to connect wires made of different materials- made of copper and aluminium.

When choosing a method, it is important to take into account all sorts of nuances, only then will it be possible to get a high-quality connection with your own hands. Twisting must be done after the power has been turned off for safety reasons.

Photo of twisting wires

When laying electrical wiring, the master will sooner or later face the need to connect wires. The durability of future wiring depends on how well this work is done.

First, the wires need to be prepared. For this, a two-wire aluminum wire should be divided into separate cores (Fig. 1). The main thing in this case is not to damage the insulation (Fig. 2). After that, using side cutters, it is necessary to remove upper layer insulation (Fig. 3). Now you need to separate the conductors with your hands (Fig. 4). The result should be a forked wire (Fig. 5).

Now with the help of side cutters it is necessary to remove the lower insulation. Moreover, the insulation should be removed in turn from each conductor. Important rule: The flat part of the clips of the side cutters must be directed towards the stripped insulation.

There are 2 types of wire connections: detachable connection and permanent connection.

Which one to choose depends on what the wire connection is intended for and on the material from which they are made. The job requires a lot of focus and attention. It must be remembered that the junction of the wires must be insulated.

Household appliances are often connected with stranded copper wires that are double insulated. For their repair, parallel twisting is best suited.

Parallel twist

Normal twist is the most in a simple way parallel connection of wires (fig. 6, 7, 8, 9 and 10). The ends of the wires should be stripped of insulation by 0.3-0.5 cm, and only then twist them together.

When removing the insulation, do not squeeze the handles of the side cutters too hard. It is necessary to make circular movements with side cutters, carefully turning them around the axis. You can twist the wires with pliers or by hand.

Each subsequent turn should be close to the previous one. Otherwise, the connection may loosen, which will lead to heating of the twisting point and subsequent sparking.

The heating of the twisting point can in some cases even lead to a fire in the wiring.

It is necessary to make at least 5-6 turns. With the help of pliers, you need to tighten the extreme turns. This will give the twist greater reliability.

The remaining free ends of the veins can be removed with pliers.

Figure 11 shows various options twists.

Bandage twist

It often happens that the conductors of the wire have a large cross section. It is very difficult to twist such wires together using the methods described above. In this case, bandage twist is usually used.

This type of twisting is shown in detail in figures 12, 13, 14 and 15.

Rice. 12	Rice. thirteen

Rice. 12

Rice. thirteen

Rice. fourteen	Rice. fifteen

Rice. fourteen

Rice. fifteen

First you need to clean the wires from the insulation, bend them at a right angle and put them parallel to each other.

After that, you need to take a small piece of soft wire and wrap it around the cores. The coils should be made as tight as possible.

To facilitate the work, the wires at one end can be carefully clamped in a hand vise.

Simple serial twisting is the usual interweaving of two or more wires. It is used quite frequently.

A little more complicated is the grooved twist, shown in Figures 16 and 17.

As in the previous types of twisting, you must first remove the insulation from the wires.

It is especially important to observe this rule for stranding stranded copper conductors.

After that, you need to tightly twist the cores of each conductor together.

For convenience, you can use pliers, but you can twist the conductors with each other and with your hands.

bandage method

Fourth day of practice. I learned how to connect wires with a bandage method.

Wire twisting can also be done using the bandage method: the stripped ends are clamped in a hand vise and wrapped with soft stripped wire (for a bandage, it is best to take copper wire diameter 0.6-1.5 mm; at the same time, the diameter of the binding wire should not be greater than the diameter of the strands being twisted). The middle part of the bandage should be made apart: if later it becomes necessary to solder this connection, the solder will better penetrate to the junction of the wires. After connecting, the ends of the wires are bent at a right angle, and another 8-10 turns of the bandage are applied on top. The ends of the veins remaining from the twisting are sawn off with a file.

The method of simple or bandage twisting is applicable only for connecting wires to each other; it is impossible to connect the wire to the contacts of electrical components by twisting.

The most convenient (and also quite reliable) way to connect wires to electrical components is to connect using contact clamps, which can be screw and spring.

Connecting wires with twisting followed by soldering

Fifth and sixth day of practice. I learned how to properly solder the wires after twisting.

The method of connecting wires by twisting is simple in execution, but it requires the subsequent soldering of the connection. The wires when twisted have few contact points, and when current flows through the connection, the contact overheats, which can cause a fire. Therefore, the connection of wires by twisting without soldering is not allowed. Soldering provides reliable electrical contact and the necessary mechanical strength.

To obtain high-quality soldering, it is necessary to choose the right solder, remove the oxide film of the contact surfaces to be joined. When connecting copper, the oxide film is removed before soldering, and when connecting aluminum conductors, during the soldering process.

The heating temperature of the soldering place should be 30 - 50 ° C higher than the melting temperature of the solder and flux. Low temperature gives the so-called "cold soldering", which has a small mechanical strength and creating an unreliable electrical contact.

The soldering iron must not be overheated when soldering. Rosin in this case begins to burn and, instead of cleaning the surface, contaminates it. In order to avoid damage to the insulation, a section of the core with a length of 2 - 3 mm is not tinned before the cut.

A feature of soldering and welding of aluminum conductors is that during the soldering process, the oxide film from the surface of the conductors to be joined is removed mechanically under a layer of molten solder or chemically - by using special fluxes, which, when certain temperature destroy the oxide film. At the end of soldering, flux residues are carefully removed, as they can cause destruction of the contact.

Soldered connections of aluminum conductors under conditions humid air not recommended due to possible corrosion. The places of soldering are protected from moisture by protective covers.

The connection and branch of single-wire and stranded copper wires PR, PRHD, PRH are used in open wiring on rollers and insulators. This method is also used in electrical wiring with flat wires PPV, etc., when branch boxes do not have inserts with contact clamps.

Rice. 3 Methods for connecting and branching wires with a twist

To connect two pieces of wire, it is necessary to tightly twist the wires of the conductive wires and cross the wires. The end of the left wire makes 6 - 8 turns around the right, and the end of the right also makes 6 - 8 turns around the left, but in the other direction.

Twisted connections must be at least 10 - 15 diameters of the connecting cores. The connections are crimped with pliers, soldered with POS-3O or POS-40 solder. The soldered twist is insulated for the entire length of the connection with the obligatory capture of the unstripped wire insulation. The connection between two twisted wires is performed in a run.

Soldering aluminum is performed with a soldering iron with solder A. If other solders are used, then a blowtorch is used. Solder A is resistant to corrosion, convenient for soldering and tinning wires. The aluminum oxide film is destroyed mechanically when the wire is rubbed with a solder stick, so flux is not required when soldering.

When soldering single-wire aluminum conductors with a cross section of 2.5 - 10 mm2, the connection and branch are carried out in the form of a double twist with a groove. Remove the insulation from the cores, clean sandpaper to a metallic sheen, overlapped with a double twist to form a groove at the point of contact of the cores.

Compound heated blowtorch or a soldering iron to the temperature at which the scion begins to melt. With a solder stick, wipe the groove on one side with effort. As a result of friction, the film is torn off and the groove is filled with solder. The groove on the other side is filled in the same way with solder. After cooling, the junction is insulated with a twist.

Technological map No. 3: Connecting wires with twisting followed by soldering