How to twist three solid wires

How to connect electrical wires or cables to each other?

Requirements are requirements, and the most popular type of connection is twisting. Where quick installation is required, terminal blocks of various shapes are used. One of the types of terminal connections is spring terminals. Wago products are especially popular.

To perform a tap without breaking the line, squeezes are used, which are called nuts among electricians. It is some type of terminal connection.

Using Terminal Blocks

The terminal block consists of contacts mounted on a plate of insulating material. The contact plate has a screw on both sides with which the wire is tightened. This allows you to press a copper wire on one side of the plate, and an aluminum wire on the other side, without fear of chemical interaction between these metals.

You can connect different types of wires. On one side, a single-core wire can be attached to the plate, and on the other, a multi-core wire. Another problem that can be easily solved using a terminal block is connecting wires with different core diameters.

The terminal block can consist of one or more contact plates, which is very convenient in installation conditions. To do this, just collect the required number of plates and secure them in the right place.

Spring terminals

Terminals of this type are very similar in design to terminal blocks. The difference is that a spring-loaded plate is used as a clamp. Using spring terminals is very simple - you just need to strip the wire to the depth of the terminal.

The pressure plate is removed and the stripped wire is inserted into the terminal. The wire is inserted so that there are no exposed sections of the wire. Then the pressure plate snaps into place and the process is complete.

Spring terminals can be used to mount single-core, stranded wires and wires of different diameters. Installation of wires from different metals is allowed. The most widely used contacts are Wago contacts, which contain bimetal plates with a special contact paste against metal oxidation.

Installation of PPE caps

PPE caps are often used when installing wiring. In appearance, they are very similar to the back plastic cap of a ballpoint pen. A cone-shaped spring is placed inside it. The spring is coated with oxidation-resistant metal by anodizing.

To connect the wires, you need to strip them to a length of 10 - 15 mm and fold the stripped sections into one bundle. The ends of the bundle are inserted into the cap, which is then screwed onto them until it stops. The PPE cap can connect several wires, the total cross-section of which will not exceed 20 mm².

They are produced in different sizes, so choosing the ones you need is easy. The caps are color-coded, which is convenient for identifying phase or neutral wires.

PPE brand	Number and cross-section of cores in mm²	Cap color
PPE – 1	2 x 1.5	Grey
PPE – 2	3 x 1.5	Blue
PPE – 3	2 x 2.5	Orange
PPE – 4	4 x 2.5	Yellow
PPE - 5	8 x 2.5	Red

PPE caps can significantly increase installation time because this connection does not require additional insulation. The cap material is made of non-flammable material and will not cause spontaneous combustion if overheated at the junction.

The quality of connection of PPE with caps is worse than with terminals and does not allow connecting wires of different metals.

Crimping with special sleeves

Where it is necessary to create a high-quality and reliable connection, special sleeves can be used. The sleeve is a piece of copper tube of the required diameter. The diameter of the sleeve is selected depending on the total diameter of the connected wires.

The stripped ends of the wires are inserted into the sleeve and clamped. Then a heat-shrinkable tube is put on the sleeve, which insulates this sleeve. If there is no heat shrink tube, you can use cambric or electrical tape. Wires can be inserted into the sleeve from one or both sides. For crimping, they try to use special hand press pliers.

With this connection, the sleeve cannot be used twice. During repairs, it is simply thrown away. If you use hand strippers and press pliers, you can perform installation with good productivity.

Soldering or welding

Installation using soldering is not used very often. Soldering always guarantees a reliable connection. The contact has low resistance and good mechanical strength. Soldered wires are less susceptible to damage due to ingress of moisture.

To connect by soldering, it is necessary to strip the wires by 40 - 50 mm, tin with rosin and twist. Then solder is applied to the twisted ends and heated until it spreads evenly over the entire twist and flows inside. The appearance of the soldered wires should be shiny.

After soldering, the sharp ends are treated to prevent damage to the insulating material. Any available type can be used as insulation.

This connection can be considered the most labor-intensive. The soldering process requires certain skills. Installation in this way at a height using improvised means is not very convenient. When connecting by soldering, it is necessary to leave some reserve in case of repair.

In some cases, a connection using the contact welding method is used. The process itself is similar to the soldering method, but the stripped twisted wires are not coated with solder. A welding transformer is used for connection. The ends of the wires are heated until they fuse into one metal ball.

For insulation, put a heat-shrinkable tube or wrap it with electrical tape on the welded ends.

Stranding and insulation

The rules of the PUE completely reject twisting, but in practice, connecting wires by twisting is used almost everywhere. But you need to know how to twist, and then it will last for decades. To do this, strip the wires according to this calculation. That the twist should be at least 4 - 5 cm long.

The cleaned areas are cleaned of the oxide film with a knife blade or fine sandpaper. The ends of the wires are crossed at a certain angle at the end of the insulation and twisted tightly with pliers. The twist should be even and tight. From above it is insulated with existing insulation.

Twisted connections cannot be made for wires of different sections. Do not twist wires made of different metals. Twisting a single-core wire with a stranded wire is not allowed. This connection is used only where there is no fire-technical acceptance of repairs.

Walnut clamp

The nut-type branch clamp is designed for making branches from main wires without breaking. At the point where the outlet is connected, a section of insulation is removed and a “nut” is attached to this place. The clamp consists of a carbolite body and a steel clamp. The clamp consists of two plates and screws. Each plate has a recess for a certain cross-section of wire.

One plate is placed under the wire and covered with another plate on top. Both plates are clamped with screws, and between them there is a wire and a tap. To choose the right “nut” depending on the diameter of the wire, you need to use the table.

Clamp type	Line cross-section mm²	Branch section mm²	Clamp dimensions
U731M	4 – 10	1.5 – 10	42 x 41 x 31
U733M	16 – 35	1.5 – 10	42 x 41 x 31
U734M	16 – 35	16 – 25	42 x 41 x 31
U739M	4 – 10	1.5 – 2.5	42 x 36 x 23
U859M	50 – 70	4 – 35	62 x 61 x 43.5
U870M	95 – 150	16 – 50	84 x 85 x 60
U871M	95 – 150	50 – 95	84 x 85 x 60
U872M	95 — 150	95 — 120	84 x 85 x 60

To make the connection, you need to disassemble the carbolite body. It consists of two halves compressed by two retaining rings. If the rings are pryed and removed, the body will fall apart. If the wires are made of different metals, then it is necessary to use an additional plate. It will prevent contact of different metals and further oxidation process, which will worsen the contact. The screws are tightened with reasonable torque and inserted into the housing.

Using a bolt

The bolt connection is most often used when it is necessary to connect copper and aluminum wires. Stripped wires are put on a regular steel bolt, and steel washers and a Grover washer are put between them. The entire “sandwich” is pulled together and wrapped with insulating tape.

What to do if there are several wires?

To connect multiple wires, you can use a terminal block. To do this, you need to connect one half of the contact plates with one wire. The number of such plates must be equal to the number of wires. The remaining wires are attached to the opposite contacts of the plates.

You can take a terminal block with a number of plates equal to the number of wires divided in half. Then one half of the wires is clamped onto one half, and the other half onto the other half of the contacts.

Multiple wires can be connected using a bolt. Place a steel washer between the wires, and put a Grover washer under the nut.

Identical wires can be connected using a PPE cap using known technology or by welding.

What to do if the wires are of different sections?

If you need to connect wires with cores of different sections, you can use:

• Soldering or welding;
• Bolted connection;
• Connection with self-clamping terminals;
• Screw terminals;
• Branch clamp;
• Copper lugs and bolted connection.

Combining stranded and single-core products

The connection of stranded and single-core wires can be made using:

• Solder connection;
• Connection with special sleeves;
• Terminal connections;
• Connection with lugs.

How to carry out work in water and on land?

All outdoor electrical wiring must be carefully protected from moisture. For installation, it is necessary to choose cable products that are designed for such work. The cable must have at least two insulating layers. In addition to the existing insulation, the wire must be placed in a corrugation. For installation in the ground - in a pipe with sealed couplings.

All sockets, switches, lamps and other elements must be manufactured in the appropriate design. On water, only low voltage is used for power supply. All connecting elements are placed above the water level.

Source: https://electricity-help.ru/ustanovka-i-podklyuchenie/kak-soedinit-yelektricheskie-provoda/

How to solder twisted copper wires

Electrical wiring in the room must be safe and convenient to use. If you strictly follow this rule, then each energy consumer (chandelier, TV, computer, refrigerator) must have its own protection device against short circuits or overheating of the wiring. You can run a separate cable from the personal circuit breaker for each outlet and switch. Two more criteria oppose this: rationality and economy.

What are distribution boxes for?

Rational wiring looks like this:

That is, the total energy consumption of the facility is evenly distributed among the circuit breakers. In addition, consumers should be divided into groups, for example:

1. Living room and bedroom lighting
2. Kitchen lighting
3. Lighting for bathroom and hallway
4. Socket group (in each room)
5. Power socket group (for powerful consumers, such as an air conditioner or an electric oven)

But with such a scheme, there may be many connections on one wiring line. It is not safe to make overhead connections and hide them in the wall. At a minimum, this does not make it possible to disable a faulty branch while leaving the rest of the circuit operational.

For normal distribution of lines, there are distribution boxes.

They are an insulated container, inside which switching (permanent) of electrical wiring lines occurs. The connection of wires in a junction box can be done in various ways, the main thing is to ensure reliable insulation between phases and a contact that can withstand the load.

The wiring diagram in the junction box allows you to save money when purchasing electrical cables, as well as avoid uncontrolled interweaving of wires in the walls. The so-called radial wires diverge from the shield with protective circuit breakers. On each of them there are connecting nodes: those same distribution boxes.

Important: The wire cross-section may be the same or different. The main condition: the power of the main cable cannot be lower than the power of the final wiring to the consumer (socket, light fixture).

In addition, there are certain methods and rules for connecting wires in a junction box. Let's talk about this in more detail.

General rules for switching electrical cables in distribution boxes

Of course, all requirements for energy supply are set out in the PUE.

This is an electrician's reference book. Moreover, there are fines for violating the Electrical Installation Rules. However, in practice, all these strictures apply only to institutions and organizations. In private households, responsibility ends with the wire coming out of the meter (electricity meter). The rest is up to the homeowner. To prevent an incorrect connection from leading to a fire or electric shock, you must follow simple rules:

• The connection of wires in the junction box is made during a complete power outage. Even if the electrician is wearing dielectric gloves and is familiar with safety rules, accidental contact of the phase wire with structural elements of the building or grounding is possible.
• The type of connection must be the same for each line within the same box. This will protect your line from loosening under load.
• Physical contact of conductors made of different materials (copper with aluminum) is not allowed. When electric current flows, active electrocorrosion occurs. Metals are coated with an oxide film, which impairs contact. The result is sparking, overheating, and complete burnout of the contact connection. If such a need arises, it is necessary to tin the wires using solder. After twisting, the connection must be soldered for at least 50% of the length. The rest of the strand will not corrode because no current flows through it under load.
• It is necessary to exclude the possibility of exposed conductors leaving the box. Even if the cable is completely laid in the wall.
• When connecting without contact devices, that is, using soldering, twisting or welding, an insulating cap must be placed on the exposed conductor. The insulator must be firmly fixed; non-combustible materials are used in its manufacture.
• The ends of the wires inside the box must have at least a 200% margin along the length of the connecting ends. In the event of a break or burnout, it will be possible to re-install without laying a new wire.

In addition, inexperienced electricians often make mistakes and break off wires when stripping the insulation. If the wire is inserted into the box under tension, reconnection will be impossible.

Methods for connecting conductors in a box

There is no single possible method. When choosing a way to connect wires in a junction box, an electrician weighs all factors: from the cost of materials to the expected load.

• Terminals. There is an opinion that this method is the most reliable, but this is a false statement. Most often, terminals are used on boxes with ready-made contact pads.

This connection of wires in the box allows you to disconnect one of the lines at any time (for example, for repairs) without causing damage to the entire power system. There are two ways to connect, directly to the block (by making a ring from a wire core), or using a terminal. With the ring everything is simple, you just need to ensure that the wire is laid in such a way that when tightening the threaded connection, the contact does not loosen.

But with terminals everything is more complicated. It is irrational to crimp a single-core wire: you can mechanically damage the conductor, and the core will break off at any moment. And when laid in a box, a single-core cable with terminals takes up a lot of space, and it is difficult to separate different phases at a sufficient distance.

An excellent result is obtained when crimping a multi-core soft cable; the contact terminal fits comfortably. But stationary installation of multi-core cable is nonsense.

Bottom line: Terminal blocks in the distribution box are convenient, but it is better to make the connection directly to the conductor under the screw, without using crimp terminals.

There are modern boxes with quick-installation contact blocks. This solution is really convenient, but is designed for light load.

Thus, the use of contact blocks is justified only if it is necessary to periodically disconnect one of the lines. And even then, sooner or later the conductor will break off.

• For standard wiring in an apartment (or household), the classics are still more suitable:

Welding wires in a junction box has been used since time immemorial. Anyone who repaired their Khrushchev or Brezhnev cars probably noticed a drop of solidified melt at the end of the aluminum strands in the boxes.

Today, the use of aluminum wiring is prohibited by the PUE, and the welding connection method is still popular. The point is this: after carefully twisting the stripped wires, the contact of the welding machine is briefly applied to the end point.

Usually this is a compact device of low power. It is used by almost all professional electricians. Works on the principle of a spot welding spotter. It will not be possible to light an arc, but the metal at the point of application melts properly. The figure shows the simplest circuit that can be assembled at home.

The connection quality is more than sufficient. In addition to the total twist length (40–50 mm), the ball at the end forms a point with minimal resistance. An additional plus is that this twist will not unwind even when moving the wires inside the box.

If a welding machine is not available, we limit ourselves to ordinary twisting. Of course, we make the connection not with our fingers, but with the help of pliers. All ends of the conductor must be stripped (but not reduced in cross-section), the length of the bare part before twisting begins is at least 70 mm.

Twisting is done after the wires are finally secured in the box. If the cable moves, the connection may become weak. The result is sparking, overheating, and contact breakage. It will be good if there is no fire.

• As an option, after twisting, the wires are soldered in the junction box.

Important! There is a widespread opinion among amateurs: under load, the twist will heat up and the solder will melt. Firstly: a load capable of heating a conductor to the melting temperature of solder is unrealistic at home. Of course, provided that the circuit breakers are in working order. Secondly: heating during twisting occurs due to loose contact, and this can be solved by soldering.

The reliability is not much worse than with welding. In this case, there is no need to purchase (do it yourself) a welding machine, a fairly powerful soldering iron, or even a hair dryer.

Tip: Use the most powerful soldering tool possible. It is better to expose the contacts to high temperatures for a short time than to heat the contacts slowly and for a long time with a weak heater.

Use refractory solders; these alloys have higher strength characteristics.

• Crimping. From the point of view of electrical conductivity, the quality of contact is no better than that of conventional twisting. But the strength of the connection increases significantly. If it is not possible to weld or solder the twist, crimp it using a special sleeve.

You can get by with pliers, but a special tool is still more reliable. There are bushings for parallel splicing of wires, and there are for fixing twists. There is no fundamental difference. If there are two or three conductors, parallel crimping is suitable. For larger quantities - crimping after twisting.

  Do-it-yourself copper car radiator repair

In fact, the methods discussed above are a modernization of the good old twisting. You should not be skeptical about the issue. Due to poor contact in the junction box, many fires occurred and damage to household appliances was caused. Therefore, when repairing electrical wiring in your home, use technical means to improve contact in the twist to the maximum.

Modern methods of connecting wiring in a box

The so-called quick fix pads. These products are widely offered in online stores and building materials markets.

Indeed, such devices make installation quick and convenient. The appearance of the connection is also pleasant. Therefore, such “electric clips” are loved by electricians who perform custom work.

However, this method has serious drawbacks. Let's make a reservation right away: the manufacturer does not promise high connection power: the characteristics are on the case. For an LED lamp, connecting a computer or TV - just right. But a refrigerator, electric stove, boiler cannot be connected through such a distribution box.

The contact area in such “quick releases” is small; the pad is connected to the conductor tangentially. With a light load, the current does not heat the surface too much. And when a serious consumer is connected, sparking, heating, and burning out of the connection will begin.

Conclusion

With all the variety of ways to connect wires in a box, traditional twisting remains the most reliable. Welding or soldering significantly improves contact.

No serious equipment is required; all work can be completed with basic electrical engineering skills.

on this topic

Source: https://respect-kovka.com/kak-spayat-skrutku-mednyh-provodov/

How to properly connect stranded wires to each other

In stranded wires, the cross-section is formed by several, sometimes intertwined, cores. Knowing how to connect stranded wires to each other, you can easily do this work yourself and get a strong contact that is absolutely safe during operation.

Where are stranded wires used?

Any stranded conductor contains at its base a large number of thin wires. The use of a multi-core cable is important in areas that require a large number of bends or, if necessary, to pull the conductor through holes that are too narrow and long enough.

The scope of application of stranded conductors is presented:

• extended tees;
• mobile lighting devices;
• automotive wiring;
• connecting lighting fixtures to the electrical network;
• connecting switches or other types of levers to influence the electrical network.

Flexible stranded conductors can be twisted repeatedly and easily, which does not negatively affect the functionality of the system. Among other things, this particular type of electrical wiring is distinguished by plasticity, and greater flexibility and elasticity is imparted to the wire by weaving a special thread, which in strength and composition is a bit like nylon.

Methods for connecting stranded wires to each other

The methods used today for electrical connections of stranded conductors are distinguished by the ability to obtain not only strong, reliable and durable, but also completely safe contact of the conductors.

Stranding of stranded conductors

This option is the easiest to implement and intuitive, not requiring the use of special equipment or professional tools.

Twisting is the easiest way to connect stranded wires

1. Strip the conductors at the ends of the conductors from the insulating layer and place them on top of each other. Twist the exposed strands overlapping each other.

   Before connecting the wires, the ends must be cleaned

2. Strengthen the twist using pliers. Simple parallel twisting is quite reliable from the point of view of contact between the cores, but vibration and mechanical forces applied to break can easily destroy the strength of such a connection.

   Use pliers to twist the wires together

The second method consists of the following steps:

1. Strip the conductor cores from the insulating layer and place them on top of each other crosswise.

   Peel the insulating layer of the wires and stack the wires on top of each other

2. Wrap one bare wire around the other over the entire surface.

   Wrap one wire around another

   Wrap the wires

3. Visually verify the strength of the winding. Using simple or traditional twisting, the electrical connection of additional conductors to the main, leading electrical wiring line is carried out.

Twisting wires using the third method:

1. Remove insulation from the ends of the conductors. Place the bare ends on top of each other and wind the first core.

   Place the wires on top of each other

2. Wind the second core, then visually verify the reliability of the connection. The sequential twisting method involves “winding” each connected conductor onto another, which ensures optimal contact of the cores.

   Wind one of the cores

   In this method, one wire is “wound” around another

There is also a fourth method, which is as follows:

1. Using a sharp knife, strip the ends of the conductors from insulation and align them along the length.

   Align the wires in length

2. Bend the connected stripped ends and wrap them with a piece of another core.

   Twist the folded strands with a piece of conductor

3. Perform a visual inspection of the connection and make sure it is secure. Band twisting consists of parallel application of the connected cores to each other and subsequent fixation of the resulting connection using a tightly laid soft conductor.

   Bandage twisting ensures a reliable connection of cores

Soldering method

Soldering the conductors using a household soldering iron ensures high-strength contact and good electrical conductivity. Tinning of stranded conductors is carried out using rosin (flux) and standard solder using standard technology.

1. Strip the wires of insulation and remove any resulting oxidation if necessary.

   Remove all oxidation from the wires

2. Heat the wires with a soldering iron tip until the flux melts and immerse the heated wire in a container with rosin.

   Heat the wire with a soldering iron and immerse it in rosin.

3. Apply molten solder to the soldering iron tip and carefully transfer it to the exposed parts of the core. After tinning, the wires should be connected to each other by twisting, which must be “tightened” with pliers.

   Tighten the twist with pliers

Terminal type connections

The use of terminals of different types is the most accessible way to connect multi-core wires in everyday life. In most cases, the terminal blocks used are divided into a couple of main types.

The principle of operation of clamping terminals involves fixing the wire using a built-in spring mechanism.

Terminals are often used to connect wires

The screw-type terminal block involves reliable fixation of all connected stranded wires using a screw. To increase the area of ​​wire contact with a conductive surface, an additional bend of the core is required.

The wires in the terminal block are secured by tightening the screws

Stage-by-stage execution of work:

1. Strip the ends of the conductor and align them in length according to the depth of the terminal block.

   Align the wires in length

2. When connecting more than one conductor to the terminal block at the same time, you must first connect the wires by parallel twisting.

   First you need to twist the wires

3. Check the reliability of the twisting and then fix the wires in the connector hole.

   Fix the wires

Crimping method

The crimping method involves connecting wires or cables using a copper or aluminum sleeve using special crimping pliers of a hydraulic or manual type.

In this case, the connection is made using a special sleeve

The pressing technology involves stripping the insulation according to the length of the sleeve, and conductors that are too thin should be connected by twisting. Then all the cables are folded together and placed inside the sleeve, after which double crimping is performed along the entire length. The method allows for a reliable and safe connection of multi-core wires made of different types of materials.

Bolted connection

The simplest, but not reliable enough way to connect stranded wires is twisting followed by bolting. This detachable connection option is most often used in open wiring conditions.

Bolted connection is the simplest, but not very reliable

To increase the level of reliability of the connection of stranded wires, it is recommended to strip the ends of insulation, then tin the cleaned areas and fasten them with a bolt.

Application of connecting insulating clamps

PPE elements are used when it is necessary to connect multi-core wires with a small cross-section (within 25 mm2). The design feature of this clamp is a plastic body with a built-in cone-shaped spring.

This method is suitable for connecting wires with a small cross-section

Stranded wires are first connected into one bundle using twisting, onto which the clamping part is then screwed. Among other things, the wire connection does not require additional insulation.

Welding method

A permanent connection is the most reliable method when working with multi-core wires. When welding is performed correctly, the general indicators of mechanical strength and contact resistance in terms of reliability do not differ from similar parameters of a solid conductor.

Welding connection of wires is considered the most reliable

Welding can be performed on alternating and direct current. At the preparatory stage, the wires are stripped of insulation, after which they are twisted and straightened by trimming the ends. To ensure that the conductors do not overheat during the welding process, it is necessary to ensure high-quality heat removal.

Security measures

In order to ensure safe operation of connected stranded wires, it is important to insulate all parts of the electrical wiring.

Proper insulation helps prevent dangerous contact of conductive parts with each other or with the human body.

When choosing an insulating material, it is necessary to take into account the operating conditions of the electrical circuit, but in most cases, insulating tape, as well as a special vinyl or heat-shrinkable tube, are used for this purpose.

If the connection area is exposed to the negative effects of high temperatures, it is recommended to use varnished cloth or fabric insulating tape as an insulating material.

Correct execution of all stages of electrical installation is of no small importance.

Only with reliable connection and proper connection of all elements of the electrical network is it possible to minimize the risk of areas with poor contact, and also prevent local overheating and electrical wiring breaks.

Multicore cables are a popular and widespread option, widely used for arranging electrical wiring for various purposes. The general rules for the separate connection of stranded and single-core conductors do not have any differences or features, therefore it is allowed to use twisting, screw clamps, PPE elements, welding and soldering for this purpose.

Source: https://aqua-rmnt.com/ehlektrosnabzhenie/kak-soedinit-mnogozhilnyie-provoda-mezhdu-soboy.html

Twisting wires: how to properly connect (twist) electrical wires - Site about

Laying electrical wiring in a 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 correctly

Connecting wires is required everywhere in rooms, in cars, devices and mechanisms, wherever there are wires. Today the following methods are used:

• Twisting;
• Welding;
• Soldering;
• Using special blocks, terminal blocks;
• Using self-clamping terminal blocks;
• Using PPE caps.

• Further in the article we will talk about the simplest way to connect wires - twisting; any home craftsman will be able to put it into practice, for example, when installing temporary wiring is required.

What you need to know about twisting

Take a close look at the photo of twisting 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 twisted area.

Method - twisting wiring with protected ends

Expose the wires by at least 5 cm, cross the ends not protected by insulation, clamp the resulting cross with pliers and twist them together using a rotational movement.

1. Bend the resulting twist so as to direct it parallel to the wire, and insulate everything.

Twisting method with winding

Strip the wires at the ends and bend them slightly in the middle, hooking the wires together at the bend. Next, alternately wrap the ends of one wire around the other.

To fix the windings and make the connection more reliable, use pliers, tighten everything and carefully insulate it.

Method of connection with the bandage

You need to know how to twist the wires correctly in this case: you will also need to prepare a bare piece of wire.

Before connecting, the wires are stripped and placed side by side so that the stripped ends touch. Use the prepared additional piece for a bandage - use it to wrap the wires.

A common method is groove twisting

First, familiarize yourself with the sequence of steps on how to twist wires with your own hands. Bend the ends of the wire into small hooks, hook them together, and wind one wire around the other.

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

• 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 and is almost impossible to break. It is preferable to use soldering when both wires of the connection have a large cross-section.

WAGO terminals greatly facilitate connection, making it more efficient; they are needed when you have to figure out how to twist copper wires with aluminum ones. The whole procedure will take place quite quickly, while the “vags” allow you to connect wires of different cross-sections, the contact will be reliable and durable.

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

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

Wires twisted together should not be immediately closed using a junction box. It is better to observe how the electrical network works for several hours, after which it is recommended to check the temperature at the mounting location. If the connection gets very hot, you need to do everything again: most likely, the contacts are unreliable.

• The twist itself is not waterproof, so it is better to take a box to connect the wires inside the wall; if without it, then the twist wires will need to be insulated using cambrics.
• All you have to do is determine for yourself which twisting method is better and consider methods for isolating nodes.

What a DIYer should know about soldering and welding

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

• Increased twist strength;
• Reduced resistance, which means the twisting area will not heat up.

Multi-core copper wiring can be easily soldered, but this method is not suitable for all wires, with the exception of twisting aluminum wires. Since soldering is fragile, you cannot be careless when performing it, otherwise you will end up with a poor-quality connection.

Welding is another method that improves twisting and 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 than soldering.

When using welding, the possibility of weakening of the twist cannot be ruled out; under the influence of high temperatures, the performance characteristics of the metal can change.

Insulation methods

Wire insulation is carried out using various types of electrical tape; it is necessary to insulate the twisted area and a section of insulated wires equal to at least 2 or 3 cm. Then it will be possible to make high-quality insulation that protects against unwanted contact with moisture; also for this purpose, special thermal tubes are additionally used.

Insulation with thermotube

1. A tube of the required length is put on one core before twisting.
2. Twisting is performed, after which the thermotube is moved to the junction of the contacts.

It is necessary that the tube adheres to the wiring as tightly as possible, so it is heated a little with a lighter.

Under the influence of high temperature, the heat tube will shrink, and it will be possible to ensure a tight grip on the wiring.

• The advantages of all kinds of twists lie in the simplicity of their execution; despite the minimal equipment, they have proven themselves to be quite reliable connections.

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

Twisting is used in loose electrical wiring that sag; this method has been adopted by motorists, since the wiring in the car is constantly exposed to vibration.

1. Among the disadvantages of twisting, the following should be noted:
2. It is not possible to connect wires having 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.
3. It is difficult to twist together multi-core cables, which are soft and may break under any tension.

• When there are several insulated wires in the wiring, due to the fact that each core is insulated separately, the total thickness can be very large.
• Twisting is not suitable when it is necessary to connect wires made of different materials - copper and aluminum.

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

Photo of wire twisting

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How to Twist Copper Wires

In the process of organizing an electrical line, modern and outdated cable connection methods are used. Twisting wires is the simplest method of fixation, but it is prohibited by the PUE. However, if you have knowledge of the correct work, you can safely make a branch or additional fastener. Such a connection will not lead to a short circuit in the future.

Danger of twisting

In paragraph 21 of Ch. 2.1. PUE twisting is not prescribed among the methods of connecting wires. The rules allow the use of welding, soldering, and clamps. The danger of twisting electrical wires lies in the following points:

• increasing the contact resistance of the contacts when the cores are loosely tightened;
• weakening of the twisted section, leading to heating;
• increase in current with weak contact;
• melting of the conductor insulation protection;
• risks of short circuits, fire, electric shock to humans.

Despite the regulatory ban, most craftsmen resort to the twisting technique. This option is suitable for testing the operation of the line, running a short-term network, for the period of repair.

Use special terminal blocks to twist the wires.

Advantages and disadvantages

The interweaving of conductors is not designed to connect powerful appliances - kettles, washing machines, heaters, refrigerators, computers. Despite this, twisting has several advantages:

• fast organization process;
• if performed correctly - durability;
• no need for special tools;
• creation of signal contacts;
• additional reinforcement when using soldering technology;
• minimum costs for consumables;
• possibility of re-execution.

Among the disadvantages are:

• mandatory insulation of the twisted section;
• normal line operation only when connecting low-power consumers;
• inconvenience of implementation;
• risks of wiring fire if the algorithm is violated;
• constant voltage drops and overload of the twisted section.

Plexus is advisable when using low-power equipment - lamps, power adapters.

Types of twists

By twisting the wires correctly, you can get a reliable and dense section. Craftsmen resort to various types of connections - safe and durable:

• Bandage - an additional one is applied to two sections and braided around them. This creates additional reinforcement of the area.
• Groove - with the parallel technique, one core remains motionless, and the second wraps around it. This type involves making 3-4 turns of one cable around the second. Then the first one is laid tightly parallel to the second one and 3-4 turns are made again;
• parallel connection. Two conductors with the insulation removed at the same level are laid side by side. The tips cross tightly and twist in any direction.

All types of twists can be used as temporary fastening.

Twisting of wires according to the PUE

The rules for electrical installations say that a section of 3-6 cm can be used for twisting. The standards allow the connection of stranded and single-core cables with the ends stripped by 4-8 cm. The stranded conductor must be laid on a single-core conductor and twisted by 4 cm.

PUE establishes the type of wire for the home line. The aluminum cable should have a cross-section of 2.5-4 mm2, copper - 1.5-2 mm2. The VVG and PV power cord is used only with a PVC sheath. Wire type ShVL and ShTB with a cross section of 0.5-0.75 mm2 - with rubber or PVC insulation.

The process of preparing veins for twisting

To twist electrical wires, you will need to de-energize the network by turning off the input circuit breaker. Next you will need:

• choose a tool with insulated handles and gloves made of dielectric material;
• remove the insulating coating from the conductors so that the metal part remains intact;
• soak a cloth in any degreaser (white spirit, acetone, nail polish remover) and wipe off the exposed parts;
• Use sandpaper to clean the area of ​​the core so that it acquires a characteristic metallic sheen.

Twisting can begin only after preparation.

Options for twisting stranded wires

A stranded wire is a wire with a metal central part in the form of thin wires. The elements are intertwined with each other, forming a lay with external insulation. Manufacturers can coat the wiring with polyurethane and add nylon threads to improve strength. The protection complicates the process of removing the insulating layer.

Twisting of insulated stranded wires is performed in several ways.

Parallel connection

The simplest option is when two stripped wires are laid crosswise, one on top of the other. Only the area without insulation is allowed to twist. Parallel twisting ensures reliable contacts, but does not protect against forceful breaks.

The technology is suitable for copper conductors - one monolithic and one stranded. Aluminum conductors with different cross-sections can also be connected in parallel. In the case of a monolithic wire, you will need to remove more insulation than from a stranded wire.

After twisting, there should be a segment left from which an additional bend is created in the direction of fixation. This technique increases the strength of the connection.

In parallel, you can fix more than 2 wires.

Sequential seam type

You need to fasten the wires together so that each of them overlaps the other:

• the conductors are stripped of the insulating coating;
• the stripped elements are stacked on top of each other;
• twisting begins from the center so that one wire wraps around the second;
• The second contact is screwed in the same way.

Due to minimal reliability, the connection is suitable for two cables.

Bandage twist

The best way to fasten a stranded wire:

• two types of wire are selected - hard for fixing and soft for winding;
• the insulation is removed from the cores so that the length of the exposed areas is the same;
• conductors are laid in parallel;
• to fix the cores together, a third stripped wire is used.

For twisted products, you need to choose more than 2 rigid cables. Winding is organized using a flexible soft wire.

Features of twisting single-core wires

To twist solid wires tightly and correctly, a parallel connection is suitable. When performing work you must:

• remove insulation at an angle of less than 90 degrees;
• act carefully if the cable material is aluminum;
• strip the insulation for the connection to a length of 3-4 cm;
• lay two cables on top of each other 1.5-2 cm above the bare area at an angle of 45 degrees;
• holding the area above the cut with your left hand, begin to twist the veins;
• work so that first there is a twist with insulation, and then a bare section;
• finish the twisting process with pliers for additional density.

The finished twist does not need to be covered with insulation right away. The line should operate for 2-3 hours. After this, you need to turn off the machine at the input and check the temperature of the node. Heating indicates that the fastening is unreliable - it will need to be redone. In the absence of heating, the conductors can be insulated.

Wire Twisting Tools

To properly twist the wires together, you will need:

• stationery or kitchen knife;
• nippers or side cutters;
• stripper;
• hydraulic or manual crimping machine;
• soldering iron - for removing insulation;
• heat shrink tube;
• construction hair dryer;
• screwdriver

Instead of a soldering iron, you can use an electric burner.

Operating procedure

The step-by-step twisting algorithm can be considered using the example of weaving a multi-core and mono-core cord. In this case, it is better to work using the branching technique:

1. Stripping the area from the end of the conductors - 3-4 cm long with a stripper or a stationery knife.
2. Placing heat shrink on one of the cables.
3. Degreasing sections without insulation with a special agent.
4. Bend the single-core end 180 degrees to further press the twist.
5. Twisting a multi-core cord over a single-core one. It will take 5-6 turns clockwise.
6. Using pliers, grasp the bent single-core tip and press it against the joint.
7. Place heat shrink in place of the twist and fix it using a hair dryer.

The heat shrink should secure the twist tightly.

Connection insulation means

The resulting assembly must be insulated efficiently. For this purpose, three technologies are used.

Source: http://9692.ru/info/kak-skruchivat-mednye-provoda/

Connecting wires by twisting - electrician's advice - Electro Genius

Almost everyone had to twist wires at least once. You will say that this is a fairly simple procedure. On the one hand, indeed, in order to intertwine several cores with each other and put them in a junction box, you do not need to have any special skills.

But not everything is so simple! After all, twisting wires is one thing, but doing it QUALITY and RELIABLY is a completely different matter.

Unfortunately, homemade twisting of wires often causes electrical fires. That is why such a procedure should be approached very responsibly. So that you can be confident in your work and not worry about the fact that somewhere you have poorly insulated or twisted the wires securely enough, we will tell you how to do everything correctly.

Why can twisting wires be dangerous?

So, let’s confirm: twisting wires is rightfully considered the most dangerous connection method. Why?

This is because the degree of contact between two or several conductors at once depends only on the quality of the work you perform. Moreover, over time, weakly bent veins will gradually become even weaker.

What does this mean? Well, at least because at high electric current loads in this zone there will be too weak contact.

The result is heating of the wires, destruction of the insulating layer and a disastrous ending in the form of a short circuit (we are generally silent about fire and electric shock).

According to the rules of the PUE, this method of connecting wires is completely prohibited. Although, of course, almost all electricians resort to a similar method in ordinary everyday work. And here’s what professional practitioners say: if you twist the wires correctly and carefully insulate them, you won’t have any problems at all. The veins themselves can serve faithfully for another couple of decades.

This begs the question - how to twist wires correctly and “forever”? Let's talk.

Reliable twisting of wires: detailed instructions

For the sake of an example, let’s take the simplest situation - it is necessary to fasten a pair of single-core wires together (let’s assume that both conductors are made of copper). The course of action is as follows:

1. Carefully strip both wires using a special tool or a simple knife, removing the insulation by about five centimeters;
2. Degrease bare contacts with acetone;
3. Take a piece of sandpaper and sand the ends of the conductors to a pronounced metallic color;
4. We lay the bare wires crosswise and slowly wrap one wire around the other (the procedure is performed using pliers, the number of turns is at least five);
5. We wind the second core in the same way;
6. We tightly wrap the twisted area with electrical tape (it would also be a good idea to use a heat-shrinkable cambric - a special tube that will protect the exposed area from the external environment).

You can safely note that there is nothing complicated in the procedure. The main thing is to expose sections of the wires by at least five centimeters and confidently twist them together with pliers, thereby ensuring strong contact.

Options for twisting single-core wires

What about the more complex situation of twisting solid and stranded wires together? Here you need to follow the first two points of the above instructions, after which you need to cross the products together and tightly wind the stranded wire around the single-core wire (at a distance of a couple of centimeters from its end).

Reeled in? Then we take the remaining single-core end and bend it in one smooth movement towards the turns of the stranded conductor. When the task is completed, the wires are insulated and placed in a distribution box. Absolutely the same course of action will help when twisting two stranded wires.

By the way, what is important is that we absolutely do not recommend twisting copper and aluminum wires. Not only professional electricians speak about this, but also regulatory documents - the same GOST.

You should not make such twists because copper and aluminum have different metal resistance indicators.

Also, when they interact, oxidation occurs, and this in turn significantly worsens the contact.

There is also the following nuance: copper and aluminum have different physical properties in the sense that one of the metals is hard and the other is soft. This will also have an extremely negative impact on the quality of contact between the two conductors.

Tips that will be useful to you

If you want to be sure of the quality of the connection you made, we recommend that you familiarize yourself with the following recommendations:

1. Have you twisted the wires, but the twisting does not seem reliable to you? Use soldering or welding! Such a connection will simply become unbreakable and you definitely won’t have to worry about the quality of contact between the cores. By the way, this option is most acceptable when the wire cores have a large cross-section.
2. Use terminals, for example - WAGO. They will not only provide a reliable connection, but will also allow you to make it much faster. Which is also very convenient - using terminals it is quite possible to connect several wires, both with different sections, and even made from different metals. The contact will be more reliable than ever. Terminals are also an excellent option for connecting wires in a chandelier or outlet.
3. Use PPE clamps. Their task is not only to make the connection reliable, but also to increase its security. In addition, such PPE caps are not at all expensive.
4. Did you twist the wires together? Don't rush to hide the connection in a junction box! Let the new electrical circuit unit operate for some time. After this, you will need to check the temperature of the wires where they are connected. If you feel that the wires are heating up, you should definitely redo the twisting!

Use these tips; they will definitely not interfere with you when performing any electrical work where there is a need to connect wires to each other.

What is important to pay attention to is that the above methods do not make the twist waterproof.

So if you are planning to fasten the conductors in the wall under a layer of plaster (and without a box), be sure to insulate the joints with cambrics.

What's the conclusion?

So we told you about how to twist wires yourself. We advise you to resort to this method only when installing temporary electrical wiring; in other cases, use more modern and safe methods. Also, never forget to turn off the power to your home before starting any electrical work. Good luck!

Source: https://orenburgelectro.ru/baza-znanij/soedinenie-provodov-skrutkoj-sovety-elektrika.html

How to connect stranded and single-core wires: an overview of methods and devices

There are different types of conductors used in an electrical circuit. There are often situations when it is necessary to connect cables with different cross-sections and heterogeneous material structure. In this article we will look at how to connect stranded and solid wires to ensure high-quality contact.

https://www.youtube.com/watch?v=a2J-6t4Rfb0

The safety of operation of the electrical circuit depends on the quality of the connection between single-core and stranded conductors. If the wrong technique is used, the following problems may occur:

1. Destruction of the insulating coating of conductors.
2. Short circuit.
3. Ignition of current-carrying conductors.

Incorrect connection of wires may cause fire

Such factors appear due to insufficient contact area of ​​the contact part of the wires. This leads to an increase in contact resistance. This indicator will gradually increase, since over time oxide will form at the site of the poor-quality connection. As a result, there will be an increase in temperature, which will subsequently lead to damage to the electrical circuit.

Possible options for connecting current-carrying conductors

There are various options for forming a high-quality wire connection. Their implementation is carried out in accordance with the PUE. It must be borne in mind that these rules do not allow the use of twisting to form a contact part between the wires. Twisting the wires is only possible to ensure temporary operation of the electrical circuit.

The following are acceptable methods for connecting current-carrying conductors.

Terminal blocks

Terminal blocks are a contact part that is coated with dielectric material. The connection is made by compressing the conductors. A screw, threaded clamp can be used for this. Products with an additional pressure plate are also available.

Note! The terminals provide high-quality contact with an easy installation process. At the same time, the cost of the products is quite low. As a rule, terminal blocks are used to connect current-carrying conductors with a cross-section of no more than twenty-five square millimeters.

Connecting wires using a screw terminal block

Depending on the type of clamp used, it is recommended to adhere to the following rules:

1. The formation of contact between single-core copper conductors is carried out using screw fixation. It involves inserting the individual ends into the brass part of the terminal, followed by tightening the screws. This technique is contraindicated for the formation of an electrical circuit from aluminum cables. This is due to severe damage to the working surface of the conductor during the compression process with a screw.
2. The use of a screw terminal device to create contact between stranded wires is also not recommended. In the process of tightening the screw, individual conductive wires of the cable may be damaged.
3. To connect stranded and single-core conductors together, it is best to use terminal blocks with a screw and a special tip. It is a plate with a flat surface that ensures tight fixation of current-carrying conductors without causing mechanical damage.

Barrier terminal blocks

PPE caps

PPE caps are widely used to form contact between wires in junction boxes. It is allowed to make connections only from identical material of current-carrying conductors. To do this, screw the cap clockwise onto the prepared bundle of conductors. It contains a locking spring that will operate at the required tightening level.

Use of PPE caps

The products in question are available in various shades and sizes. They have excellent connection quality and low cost.

Special sleeves

To connect cable cores by pressing, you will need to use sleeves and specialized pliers. The sleeves are made of copper and aluminum for a specific type of wire material. Universal brass sleeves are also available. With their help, you can form contact between aluminum and copper conductors. Pliers are necessary for high-quality pressing of the sleeve. They come in two types:

Crimping twists with sleeves

The sleeves can be shaped like ferrules to group cable lines in front of the terminal box. The main criterion when choosing a sleeve is the cross-section. They allow you to make any connection combination - three-core with two-core or single-core cable.

Soldering and welding

Forming contact between conductors by soldering or welding helps to obtain a reliable connection. But this method requires the use of special equipment, as well as skills in working with it.

To carry out soldering you will need a soldering iron, rosin and solder. The surfaces to be joined are first prepared. Here problems may arise with multi-core cable lines, so each individual core will need to be processed. In the future, the education process is almost identical. Initially, the conductors are connected by twisting, after which solder is applied.

Connecting wires by soldering

When welding is involved, preparatory work will also be required. The essence of the method is to melt the ends of the connected conductors. After they harden, a high-quality connection is obtained. Using this method, it is possible to form a contact between an unlimited number of conductive wires.

Note! After completing the work of connecting current-carrying conductors by welding or soldering, you will need to apply a protective layer of insulation. You can use electrical tape or heat shrink tubes as it.

Formation of high-quality contact between flexible and rigid wire

To create reliable contact between single-core rigid and multi-core flexible wires, it is recommended to use welding or soldering. The first option involves pre-melting the cores of the flexible cable so that they merge into a single whole. Subsequently, rigid and flexible wires are welded.

Soldering of the elements in question is carried out as follows:

1. Initially, a flexible conductor is wound onto a rigid core.
2. The exposed edge of the rigid cable is then bent so as to clamp the stranded conductor into a loop.
3. At the final stage, the connection is soldered and insulated.

Twisting the wire before soldering

Safety rules and preparation of connected conductors

Direct twisting of single-core and stranded wires without further processing does not meet safety regulations. Over time, such a connection can lead to a short circuit and fire in the electrical circuit.

Regardless of the wire connection method used, careful preparation of the contacting parts should be carried out. It consists of stripping the required area of ​​the insulating layer. After this, it is recommended to degrease the contact part or treat it with rosin. Next, the surface is cleaned with sandpaper. Upon completion of the connection of current-carrying conductors, their high-quality insulation should be ensured.

All work must be carried out on a de-energized network using personal protective equipment.

To ensure a high-quality connection between single-core and stranded wires, you can use any of the presented methods. In this case, you will need to take into account the number of connected cores, as well as their cross-section.

How to connect stranded and single-core wires: an overview of methods and devices

Source: https://220.guru/electroprovodka/provoda-kabeli/kak-soedinit-mnogozhilnyj-i-odnozhilnyj-provod.html

Connection of large cross-section wires

The electrical circuit is located over the area of ​​virtually the entire frame, providing the room with electricity for household and industrial appliances, depending on the purpose of the building.

Essentially, a cable is supplied from the central network, which is subsequently placed in the switchboard, from which several more come out, are routed to different ends of the room and connected to the distribution box, from where the final wires come out, ultimately connected to sockets, switches, etc. . Precisely in the distribution.

boxes create the largest number of connections, and sometimes a soldering iron, welding, or connectors are not used there, but wire twisting is used, which does not require special devices or tools, but only those things that virtually everyone has (knife, pliers).

How to properly twist wires

In order to virtually reduce the possibility of short circuits and ignitions, the twists in distribution boxes must be made with high quality. If a person performs such an action for the first time, it is better to first carefully read the rules of such a connection, and only after that begin to perform the work. Let's figure out how to do twists correctly, what types there are, and what problems you may encounter when performing this work.

To begin with, it is worth saying that connecting two wires of different metals by twisting is not recommended. Many analytical articles and arguments have been written about this as to why this should not be done:

• different coefficients of thermal expansion (metals react differently to heating and cooling, as a result of which the contact gradually deteriorates);
• the appearance of an oxide film on the aluminum wire (it does not allow current to fully flow, the wire heats up and breaks down over time);
• structural destruction of aluminum during electrolysis (these two metals form a galvanic couple, and after exposure to a humid environment, the metal ends are subject to heating and subsequent destruction).

Twisting of copper and aluminum wires

Copper and aluminum cannot be connected directly to each other. However, in many houses there are aluminum wires that need to be connected to copper wires, and twisting is sometimes the only way to connect. In this case, it is important to adhere to certain rules that will allow such fastening to last as long as possible.

• To begin with, it is worth noting that the conductors must be tightly wrapped around each other. If their diameter is significant, there must be at least 3 turns, and if the diameter is up to 1 mm, in this case it will be necessary to wrap the wire around each other more than five times to ensure high-quality transmission of electrical flow. Also, after this it is very important to treat the bare surface with a special varnish that is resistant to water and moisture.
• When connecting copper and aluminum wires, it is better to use a special steel plate placed between them. This will avoid their direct contact. Thus, the service life of such a connection will be much longer. If you don’t have such a component at hand, then you can resort to treating the bare copper wiring with solder, which will also avoid mechanical contacts of these two metals.
• The ideal solution for connecting copper and aluminum conductors is to first apply solder to the copper core. Especially such pre-treatment is often used when connecting single- and multi-core wires, when in this way a wire consisting of several conductors is converted into a single-core one.

Twisting wires of different sections

This type of work implies the unambiguous use of additional means for connection. Such devices can be screw clamps, self-clamping terminals, bolts, tinned copper lugs, and walnut-type holes. Also, in order not to purchase additional components, you can use soldering or welding, or other methods of connecting wires.

If the difference in the diameter of the wires is insignificant, for example, 4 and 2.5 mm, then connecting them by twisting is not so difficult. To do this, you need to carefully wrap them around each other, after which you need to use welding or soldering. This fastening of two conductors will last for many years without complaints.

In other cases, twisting wires will not be reliable and durable. In such situations, you simply cannot do without additional components. In various situations, certain devices are used:

• if the cross-section of the wires is large, it is best to use a self-clamping terminal;
• for branching from the main line to the distribution. The shield uses a branch compressor, which among experts is also called “Nut”;
• To connect wires with a large diameter, a copper-tind tip is used.

Errors when twisting wires

The most common problem with connecting conductors in this way is that one wire wraps around another. This is completely wrong. The wires must evenly wrap around each other, thereby ensuring reliable passage of electric current and creating mechanical strength so that such fastening will last for many years.

The length of the twist depends directly on the diameter of the conductors themselves. It is worth considering that the minimum threshold for this characteristic should be no less than 3 cm. Otherwise, everything depends on the diameter of the wires: the larger the diameter, the greater the length of the created twist should be, but there are no specifically prescribed standards in this regard, Each specialist decides for himself what this value should be in order for the connection to be reliable and of high quality.

Source: https://1000eletric.com/soedinenie-provodov-bolshogo-secheniya/