What is wire twisting

Ways to twist wires - electrician's advice - Electro Genius

Wire twisting is one of the methods when it is necessary to make a branch or additional wiring connection. However, according to the PUE it is prohibited to use it. But knowing how to twist wires correctly, you can really avoid unforeseen incidents, especially short circuits, which often lead to fire.  

Connecting wires

To ensure full electrical conductivity, the integrity of the wiring is an important point. Damage or poor-quality adhesion is unacceptable.

It is important to ensure tight contact contacts and reliable connections in the “electrical node” areas. There are certain methods for eliminating breaks in cables. Among them, welding should be noted.

It applies to copper and aluminum wires. This ensures a particularly reliable grip.

Connections can be divided into types:

• twist;
• welding;
• soldering;
• pressure testing;
• terminal blocks;
• self-clamping terminal blocks (WAGO terminals);
• PPE caps;
• bolt clamp.

Connection methods

The most complete connection for wires made of copper is soldering. It can be easily accomplished using flux (rosin, borax) and tin solder. Terminal blocks are also used - a special device that is made using screw terminals. They are selected separately in accordance with the cross-section of the cores.

Self-clamping terminal blocks are often used to save time on electrical installation work. In order to isolate a twisted or soldered electrical connection, PPE insulating caps are used. Today in the energy sector, WAGO terminals are widely used, which are produced for wires and cables of various diameters.

In addition, WAGO terminals allow you to connect conductors made of different materials (copper and aluminum).

The choice of which connection to use depends on various factors:

• material (steel, copper, aluminum);
• number of twisted elements;
• section;
• place of work (house, street, in the ground, etc.).

Types of twists

Reliable and tight twisting protects against unforeseen emergency situations. It is important to do it as correctly as possible. Even the slightest violation of safety regulations can cause a fire.

For this reason, the rules for the design of electrical equipment do not provide for the legal use of this method. Despite the ban, it is relevant both in production and in everyday life.

Existing types of wire twists can be used temporarily when, for some reason, a quick connection using safer methods is not possible.

There are simple methods by which the connection can be made safely and firmly. They are not difficult even for a beginner. When performing, it is possible to use both two wires and several. The following known types of twists are usually used:

• bandage;
• groove;
• simple branching method.

Types of wire twists

The above twisted electrical wires are completely reliable electrical connections. But implementation requires certain skills with hand tools. Self-training is available to every person who practices repairing electrical wires.

Bandage is one of the methods of twisting wires, often used in everyday life. It is characterized by the use of an additional segment, which is superimposed on the connected conductors. This is a good method for serial, parallel and branch connections.

Stranded

Beginners sometimes wonder: “how to connect single-core and stranded copper wire?” In fact, the main requirement is a tight and reliable fit of the cross-sectional area of ​​the cores to each other.

Knowing how many wires can be twisted into one twist, you can quickly complete the task. The number of electrical conductors depends on their cross-section. The larger it is, the fewer wires are allowed to twist.

And vice versa: the smaller the cross-section of the conductive wires, the greater the number of wires that can be twisted.

Connecting stranded wires using the groove method is not difficult. This is an easier way to do the job than the “bandage”.

In this connection, it is not necessary to use an additional piece of wiring. In this case, a complete connection of wires by twisting is carried out directly by the wires themselves.

They are laid in parallel, in series or in a branch.

Before twisting the three wires together, it is necessary to remove the insulation from the ends of the wires and use a hand tool to twist them. It is permissible to use the “groove” and “bandage” methods, as well as a simple branch.

The maximum number of wires in a twist using the latter method depends on the diameter of the conductor. Even with the smallest diameter of the cores, their number should not be more than six. Novice electricians are wondering: “how to make a twist of 4 wires?”

  It is most optimal to perform this action using the “groove” or “simple branch” method.

Twisting of wires according to the PUE

The twisting length of wires according to the PUE ranges from 3 cm to 6 cm, depending on their diameters.

Twisting single-core with stranded is carried out as follows:

1. The ends are prepared at a distance of 4 cm to 8 cm.
2. A multi-core current-carrying core is superimposed on a single-core one and wound up to a length of 4 cm.

Wire Twist Tool

This task requires certain tools. Among the mandatory ones:

Hydraulic manual press KVT “PGR-70”

You will also need a twisting attachment and insulation material. When working with these tools, it is imperative to comply with safety regulations. Certain job skills will be required.

Although in some cases it is possible to twist wires protected by insulation by hand, today a wire twister is usually used. It greatly simplifies the work and guarantees high quality results.

There are also small devices that allow you to speed up the twisting of the cores. Such a device is inserted into a screwdriver and twists them by rotating them.

Twisting devices

Connection isolation

An important requirement in the connection procedure is their isolation to avoid accidents. Insulating materials include:

• PVC tubes;
• insulating tape;
• heat shrink tubes;
• special twist insulator caps.

Wire insulation methods

Methods of insulating wires directly depend on the material used. They are divided into methods such as planting, reeling and heating.

In the first case, the material is placed on the twisted segment. In the second, simple winding is performed using insulating tape.

In the third, insulation with a heat-shrinkable tube involves placing it on the current-carrying part and then heating it.

To the question of beginners, “Is it possible to insulate wires with electrical tape?” should be answered unequivocally in the affirmative. This is one of the most common methods. The main requirement is compliance with the shelf life of the material and the absence of visible damage.

Despite the fact that at first glance the procedure for twisting electrically conductive wires seems simple, a responsible approach to the matter is required.

Source: https://orenburgelectro.ru/podklyuchenie/sposoby-skrutki-provodov-sovety-elektrika.html

The easiest way to connect wires: how to twist them together correctly?

When installing a branch in a junction box, and also when it is not possible to lay the line with a single piece of cable, the wires have to be connected.

There are different ways to do this and one of them is twisting. Can it be used, in what form and how to twist the wires correctly.

Twisting wires together according to the PUE

Twisting in its pure form, that is, when the wires wrap around each other without additional fixation, is prohibited according to the PUE. The reason is that, due to the elasticity of the metal and due to repeated heating-cooling cycles, the contact gradually weakens, which means the contact resistance increases.

In the old days, when the list of electrical receivers in an apartment was limited to a TV, lighting and a low-power iron, this was not a threat, so twisting was used everywhere.

With the advent of water heaters, multicookers and other powerful equipment in everyday use, the strength of the current flowing in home wiring has increased significantly, and under such conditions, an area with even low resistance quickly heats up to the point where the insulation melts or ignites.

Nevertheless, every electrician must be able to twist correctly, since for high-quality welding or soldering of wires they must first be twisted. In addition, twisting can be useful as a temporary method if you do not have a terminal block or other clamp at hand.

Twisting methods

There are such types of twists: parallel, sequential, bandage. There are also varieties for connecting stranded conductors.

Types of twisted wire connections

How to twist it with your own hands?

Usually in everyday life, when reorganizing the wiring, the home handyman is faced with the question of how to properly twist the wires in the junction box. In this regard, each of the listed methods is worth considering in detail.

Parallel

They operate in this order:

1. at a distance of 7-8 cm from the end of each core, cut the insulation and remove it. It is important not to damage the core itself, otherwise it will break off when twisted. If a regular knife is used, the cut is made obliquely, directing the blade almost along the conductor. The latter is rolled with a finger on the table. It is more correct to use a special tool - a stripper or an electrician's knife with a heel. Such a tool is physically unable to make a deep cut in the insulation, so that the core is guaranteed to remain undamaged;
2. clean the wires to a metallic shine with sandpaper;
3. fold the wires crosswise where the insulation ends;
4. holding the wires at the intersection point with some pliers, twist them into a tight bundle with the other. To avoid damaging the insulation with the tool, they are wrapped with electrical tape;
5. with pliers they cut off the ends of the veins sticking out to the sides, making the same twisting movement;
6. isolate the connection (insulation methods are described below).

The recommended twist length is 15 core diameters. The minimum permissible length is 10 diameters.

It is inconvenient to grab thin wires with pliers; they are twisted by hand. To do this, they are folded in parallel, and the ends are bent so that you can grasp them with your fingers.

Sequential

Consecutive twisting exceeds the previous one in strength, order of execution:

1. the bare and stripped veins are folded crosswise, so that the intersection point falls in the middle of the bare area;
2. The 1st wire is wound onto the 2nd, moving from the intersection point to the insulation;
3. The 2nd wire is wound on the 1st according to the same scheme.

This method can withstand tensile forces better than the parallel method. This option is also more preferable for circuits subject to vibration, for example in a car.

Twisting in automotive wiring is used only as a short-term temporary option. Permanent connections here are made using crimp sleeves.

Bandage

The bandage method is implemented like this:

1. the connected conductors are applied one to the other in parallel;
2. tightly wrap a piece of wire around them (you must use a fairly flexible one);
3. isolate the connection.

Before insulating the twist, it is recommended to check it. Having connected the load, use the line for several hours, and then, making sure to de-energize it through the circuit breaker, check the twisting temperature. If it is hot, the contact is bad, the connection is redone. In this case, the ends of the strands are bitten off - they cannot be twisted again.

Safety precautions: before touching bare wires with your hands, you should always check the absence of voltage with a phase indicator.

How much can you twist into one twist?

Up to 6 wires are combined using the twisting method. More than 2 cores are connected by parallel or bandage twisting, while serial twisting is only applicable for 2 cores.

Parallel twisting of several cores (more than 2) is done as follows:

1. the stripped wires are straightened and folded together parallel and in the same plane;
2. holding the place where the insulation ends with some pliers, with the other they bite the ends of the wires and twist them as tightly as possible;
3. bite the ends of the veins with wire cutters, making a twisting motion;
4. isolate.

If it is necessary to make a large number of twists, use a screwdriver: clamp the ends of the cores in the chuck and activate the tool. In order not to hold a bundle of wires in your hands, it is useful to make a simple device in the form of a washer welded to the rod.

Stranding of stranded conductors

Stranded strand (sometimes mistakenly called stranded) is made up of several thin wires, which gives it flexibility. These wires are used to make power cords, portable sockets and extension cords.

They are also used in distribution boards, where, due to the close proximity of devices and tight spaces, the cable has to be bent strongly. Due to their flexibility, twisting stranded wires using any of the methods described above does not provide high-quality and durable contact.

Twisting of stranded wires

The following method is used:

1. each core is dissolved into two or more bundles (depending on the number of wires);
2. apply the wires one to the other and twist bundles from different wires in pairs;
3. the resulting bundles are twisted into one.

All that remains is to isolate the connection, as usual.

Is it possible to twist copper and aluminum?

To the question of whether it is possible to twist a copper wire with an aluminum one, the answer is clearly negative, for two reasons:

1. corrosion . Different metals in the contact zone are always destroyed due to corrosion, electrolytic or atmospheric. The rate of destruction for each combination is different and in some cases it is relatively low. But there are pairs of metals, upon contact of which corrosion occurs especially intensely. The combination “aluminum - copper” belongs to this group. As a result of chemical changes, the conductivity of metals drops sharply and the connection heats up;
2. difference in coefficient of thermal expansion . Because of it, heating-cooling cycles will lead to weakening of the twist and, as a result, deterioration of the contact.

There must be an intermediary between aluminum and copper - brass or galvanized steel; to connect such conductors the following is used:

1. terminal blocks: wires are inserted into different terminals;
2. sleeves for crimping of the GAM brand (half is made of aluminum, the other is copper);
3. soldering using special solder and flux;
4. bolt clamp with a galvanized washer between the aluminum and copper conductors.

Sequence of actions when using bolt clamps:

• put a washer on a small diameter bolt or screw;
• twist the end of one strand into a ring and put it on next;
• put on a galvanized washer;
• twist the second core into a ring and also put it on;
• use another washer and tighten the connection with a nut.

Contact of aluminum with tinned copper is also allowed.

In air, aluminum quickly becomes covered with an oxide film with high resistivity, to avoid which the ends of the cores of this metal are lubricated with quartz-vaseline paste before making the connection. This paste is added to terminals and connecting insulating clips (PIC) for aluminum wires at the production stage.

If the wires are of different sections

If there is a large difference in the cross-section of the wires being connected, the following method is used:

1. strip the end of the thicker core to a length of 8 cm;
2. a thinner wire, also previously stripped, is tightly wound into the middle of the bare area (so that the winding length is 2.5 cm);
3. bend the exposed sections of the thick wire on both sides of the winding in a U-shape and crimp with pliers so that they fix the turns of the thin wire;
4. isolate the connection.

In the same way, you can connect a single-wire core to a multi-wire one: the second is wound on the first and further in the text.

Insulation methods

The twist is insulated with electrical tape, heat-shrink tubing, and special PPE elements.

Insulating tape

Insulating material for use in dry rooms.

It is a tape with an adhesive layer made from the following materials:

• PVC;
• paper and acetate fabric;
• epoxy and polyester films;
• fiberglass and mica.

PVC tape is best suited for household use. The highest quality variety, recommended for use, is made from class A PVC film and coated with rubber-based glue.

The end of the tape is glued to the insulation near the beginning of the bare area and then wound, moving towards the end of the twist and partially overlapping the previous one with each subsequent turn. Having gone around the end of the twist (it should not just be wrapped, but covered with tape), move in the opposite direction. The electrical tape is wound in at least two, and preferably three, layers.

Heat-shrink tubing

A more reliable insulator, suitable for use in rooms with high humidity and even outdoors. The tube is made of a special polymer that shrinks in size when heated.

The product is installed as follows:

• a heat-shrinkable tube is placed on one of the wires to be connected;
• perform twisting;
• slide the tube onto the twist;
• warm up the insulator with a hair dryer or, in the absence of one, with a lighter. As a result, the tube will shrink and tightly wrap around the twist.

Heat-shrinkable tubes are available in different diameters for wires with different cross-sections.

For reliability, it is recommended to insulate the twist with two heat-shrinkable tubes.

Connecting insulating clamps (PPE)

The product not only isolates the twist, but securely fixes it, and such a connection no longer contradicts the PUE and other regulatory documents. PPE (also called insulating caps) is a polymer tube, capped at one end and equipped inside with a steel conical spring made of square wire .

When screwing the connector onto a twist, the spring, especially its narrow part, tightly presses the wires one against the other. PPE differs in size and it is extremely important to choose a product that matches the cross-section of the cores and their number . There are caps for connecting 2 wires with a cross-section of 1.5 mm2, 4 with a cross-section of 2.5 mm2, etc.

It is customary to paint them in different colors, but there is no standardized system - each manufacturer adheres to its own colors. If you choose the wrong PPE, then either the spring will not crimp the wires with sufficient force (the cap is too large), or they will not fit into the narrow part of the spring (the cap is small). Connectors for aluminum wires contain quartz-vaseline paste.

Source: https://proprovoda.ru/provodka/provoda-i-kabelya/kak-pravilno-skruchivat.html

What is better: twisting or soldering wires?

There is wiring in every house. And the correct connection of wires is part of the safety of the electrical network and its trouble-free operation.

Installation of electrical wiring in an apartment or cottage involves connecting the wires of distribution boxes and switchboards. The safety of the electrical network and its trouble-free operation depend on how correctly and efficiently all connections are made.

Correct connection of electrical wires

 
Methods for connecting electrical wires

Electricians use the following methods for connecting wires:

• twisted;
• soldering;
• using terminal blocks;
• crimping;
• with bolts;
• plastic PPE;
• “Wago” – spring terminals;
• "nuts" made of plastic.

The choice depends:

• from the material of the wire (cable) cores;
• on the operating conditions of the electrical network (external or internal wiring, hidden or laid openly);
• from the cross-section of the connected conductors;
• on the number of cores in one connection.

The connection of the distribution box wires must be made in such a way as to ensure reliable contact and avoid heating the wires. Here is an overview of the above methods for connecting current-carrying conductors.

 
Features of using terminal blocks to connect electrical wires

 
The terminal block consists of a plastic housing, a brass or copper bushing with threads and screws located on both sides.

This device allows you to:

• save on electrical equipment: the terminal block is cheaper than other connectors;
• connect the wires securely;
• connect cores of dissimilar metals (copper with aluminum);
• reduce installation time.

Disadvantages of terminal connectors:

• unsuitability for connecting more than two conductors;
• difficulties when connecting aluminum conductors: if the screw is over-tightened, the metal may break;
• unsuitable for use with multi-core wires.

The connection of electrical wires in the terminal block is carried out as follows.

The outer insulation is partially removed from the cables and the cores are exposed. The length of the bare conductor depends on the size of the terminal.

The length of the wire section without insulation is checked, for which you need to unscrew the terminal screw and insert the core completely into the hole. The excess is cut off with side cutters.

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

To improve contact, the copper wire is tinned. The connected cores are inserted into the terminals one by one and clamped with screws in several stages.

The reliability of the connection is checked.

Tip: in order to remove the insulation without damaging the core, it is recommended to use a special tool. If this is not available, only the surface layer of insulation is cut in a circle with a sharp knife, after which the wire should be bent along the cut line. After breaking, the insulation is removed with a light movement of pliers.

 
We use spring terminals to connect electrical wires

The connection of conductors with spring terminals is carried out using springs that press the contact plate to the metal of the core. The mechanism is driven by a special lever.

Wago type terminal connector

The Wago technology has a number of advantages over other installation methods:

• allows you to connect aluminum wires with copper;
• can be used to connect more than two wires;
• allow you to switch wires in small junction boxes;
• installation is carried out efficiently and in the shortest possible time;
• conductor cores are not damaged;
• After installation, it is possible to check the continuity of the circuit using a device probe or indicator through a hole in the housing.

In order to connect the wires using Wago terminals, it is necessary to remove the insulation so that the exposed wires are not visible, then insert the wires into the connector sockets and press the levers until they stop.

Note: Wago spring terminals are available in reusable and disposable versions. The latter, if it is necessary to repair the connection, are cut off, after which new connectors are installed.

Connecting conductors using PPE caps

The PPE cap is screwed onto the connection clockwise

The abbreviation PPE means “connecting insulating clamps”. The connector is designed as a spring located in a plastic housing. The spring securely holds the wires together, which creates reliable contact. Advantages of this method:

• the ability to mark wires using colored caps: the “phase” conductors connect red PPE, “zero” – blue or white, “ground” – yellow or green;
• fire protection: connector bodies are made of non-flammable plastic.

Important: connecting copper and aluminum wires using PPE is not allowed.

Crimping with sleeves

Connecting conductor cores with sleeves

The method consists of putting a metal tube (sleeve) on the cores freed from insulation, which is crimped with press pliers. As a result, the conductors are tightly connected to each other. The connection point is isolated.

Important: connections of aluminum and copper conductors may only be made using sleeves specially designed for this purpose.

Welding or soldering technology allows you to obtain a reliable connection of wires

The disadvantage of this method is the inability to monitor the integrity of the network after installation and isolation, as well as the non-repairability of such a connection. Additionally, a DIY soldering torch is dangerous to use.

An alternative to soldering wires is to weld them. The process involves the use of a welding machine.

 
Wire welding technology

When connecting copper wires this way, it is recommended that you try out a DIY copper wire soldering transformer before you begin. It is important to know that copper is smelted at a temperature of 1080 °C, but above 300 °C this metal becomes brittle.

In the absence of a special soldering device, use a conventional inverter welding machine. The step-by-step process of welding wires is as follows.

Up to 10 cm of insulation is removed from the ends of the wires.
The cores of the connected wires are tightly twisted together. The result should be twists approximately 5 cm long.

The ground cable of the inverter apparatus is connected to the twist closer to its beginning.
The current adjustment knob is set in the position from 30 to 90 A (at a voltage of 12 - 36 V): the value is selected depending on the cross-section of the wire and their number.

The carbon electrode of the welding machine briefly (no more than 2 s) touches the twist so that an arc is formed. As a result, a welded monolithic joint is formed at the tip of the twist. After complete cooling, the connection is insulated with heat shrink tubing or adhesive tape.

At the ends of the cores connected by welding, a monolithic alloy is formed

Connecting electrical wires by soldering

Soldering copper wires is an old, proven method that allows you to obtain a reliable electrical connection. The technology allows the installation of monolithic and stranded wires of various sections. There can be several conductors in one connection.

The work is performed using the following technology.

The insulation is removed from the ends of the connected conductors using a special device (approximately 5 cm).
The strands are tightly twisted together manually or using pliers (depending on the number of strands and their sections).

The twist is treated with flux or rosin.
This is necessary to improve the quality of soldering. On an open fire (using a gas burner or a gasoline blowtorch), a cup soldering iron (futorka) is heated red-hot. The cup of the futor is filled to the brim with tin-lead solder grade POS 30, POS 40 or POS 61.

The solder is heated to the point of fluidity.
The twist is briefly (up to 1 second) completely dipped into the futor cup, as a result of which the solder should completely cover the exposed wires.

After natural cooling, the twist is insulated with PVC adhesive tape or a plastic cap.
Important: soldering of wires should be done with safety glasses and tarpaulin gloves. During work, fire safety rules must be observed.

Soldering copper wires is performed as shown in the video.

Connecting wires with simple twisting

Wire connection diagrams in a distribution box for low-power electrical networks can be implemented by simple twisting without the use of additional fixing means. In this case, it is important that the twisting step is as small as possible, and its length is at least 20 mm. Only cores made of homogeneous metals are connected in this way: copper - with copper, aluminum - with aluminum.

It is not allowed to use this installation method in damp rooms and in wooden houses.

After twisting, the wire connection should look as shown in the photo

Walnut clamp

For connecting wires with a cross-section of 4 square meters. mm and it is more convenient to use a “walnut” clamp. It consists of a pair of specially shaped plates that are pressed together with screws at the corners. Advantages of the method:

• ease of connection;
• the ability to connect copper conductors with aluminum ones;
• comparative cheapness of materials.

Important: the “walnut” clamp is not used in distribution boxes (dimensions do not allow). To ensure reliable contact, the screws must be tightened from time to time.

Using a bolted connection to connect electrical wires
To connect large cross-section wires, as well as to install grounding elements in an electrical panel, a bolted connection is used. The ends of the wires, freed from insulation, are screwed onto the bolt threads in a clockwise direction. The connection is pressed with a washer with an engraver and a nut, after which the bolt is isolated.

Source: https://rem-serv.com/chto-luchshe-skrutka-ili-payka-provodov/

How to twist wires correctly

No matter how common various clamps and terminals have become recently, the most popular method of connecting wires is simple twisting. However, you should know that electrical installation rules prohibit the use of twisting in its pure form (that is, without further soldering or welding of the contact). You can increase the “legality” of twisting with the help of PPE. You make a twist, and on top of it you screw the PPE (connecting insulating clip).

It creates sufficient contact density and, under different loads and temperature changes, does not allow the contact to become loose. You can select PPE of the required size, quantity and quality with free delivery here.

Types of twists. Errors when twisting

Firstly, remember that wires come in aluminum and copper. Copper wires are divided into monocore (one solid core) and multicore (flexible).

Monocores are used for stationary connection of equipment. Once I laid it under the plaster, behind the drywall and forgot about them. There is no longer any need to move or bend such wiring.

Multi-core cables are used for mobile devices or temporary connection of electrical equipment. Where wiring constantly needs to be moved from place to place, its location must be changed. These are home carriers, household appliances plugged into sockets.

They are also used in the assembly of switchboards, where there is a shortage of free space, and the conductors have to be significantly bent in order to be inserted into the terminals of the devices.

Let's first consider how to properly twist wires from a single core. The process here is not complicated and is known to everyone. Take two wires, strip them at the ends and begin to twist each other.

The Chinese even came up with an assistant attachment in this matter to automate the work. More details

Main features and rules:

• ⚡wires must be made of the same material (copper or aluminum)
• ⚡strip the core at least 3-4 cm, thereby increasing the useful contact area
• ⚡wires are laid parallel to each other
• ⚡both wires must be twisted evenly together
• ⚡When twisting, use some pliers to hold the place where you start stripping the insulation, and use the other to twist at the end. The insulated parts of the conductors must not be twisted together.
• ⚡the number of turns that should end up being five or more

Twists of aluminum and copper wires are performed in the same way. The difference is that you can unscrew and tighten copper ones several times, and aluminum ones 1-2 times. After which they will break off.

What if you need to twist more than two wires, say 4-5? The process is no different:

• ⚡slowly twist the wires with your hands, only giving them the shape of the future twist
• ⚡take two pliers and, holding the twist at first, tighten the wires at the end
• ⚡the length of the stripped areas should also be 3-4cm

There are situations when it is necessary for the twist to take up as little space as possible. Either there is not enough space in the junction box, or it must then be pulled through a narrow hole. In this case, the technology is slightly different.

• ⚡place the stripped wire strands crosswise in the middle of the stripping area
• ⚡and begin to twist them so that the ends after folding are equidistant from each other

In terms of quality and reliability, such twists are inferior to conventional ones.

Twisting copper wire with aluminum

Copper and aluminum wires cannot be twisted directly. Such a connection will oxidize and subsequently can lead, at best, to burnout of the contact or, at worst, to a fire. In such cases, you need to use either connectors, or use a third metal - steel, as a spacer between copper and aluminum.

Take a simple bolt with a nut and washer. The stripped wires are shaped into a ring at the end. And these rings fit on the bolt. Moreover, the wire of the ring should bend in the direction of the bolt thread.

The aluminum core is clamped with a steel washer, and a copper washer is placed on top of this washer. After which the contact is tightened with another washer and nut. That is, to create normal contact between a copper conductor and an aluminum one, you will need at least a bolt with a nut and 3 steel washers.

Twisting stranded wires

You can apply the previous descriptions of work for such conductors, but this will not provide reliable mechanical contact. Therefore proceed as follows:

• ⚡stranded wires fluff out (the strands are spread out to the sides) and are divided into two “pigtails”. You can make several braids, depending on the cross-section of the wire.
• ⚡the wires are placed one on top of the other and twisted one pigtail from each wire together
• ⚡at the end, two “braids” obtained from four are woven into one solid twist
• ⚡the result is a reliable twist with good mechanical contact

In the end, I would like to especially note that the types of twists considered do not always provide good mechanical contact.

For reliable electrical contact, it is recommended to solder or weld them together. Then you will be 100% confident in the safety of the electrical wiring of your apartment.

//www..com/watch?v=HaOY0CfDLEo

Source: https://domikelectrica.ru/kak-pravilno-skruchivat-provoda/

Twisting wires: is it possible to do it, methods of twisting

June 13, 2018

353 views

Any person who has at least occasionally carried out repair work on electrical circuits knows well what twisting wires and that this is one of the simplest and most accessible connection methods.

However, if the work is performed incorrectly, there is a high probability that the electrical circuit will stop functioning and the room will be de-energized, and in the worst case, it can lead to ignition and a fire.

To prevent this from happening, to perform correct and safe twisting, you must adhere to certain rules and expert advice.

Is it possible to connect wires by twisting

This method of connection has long been replaced by other types. This is due to the fact that there are now many devices on sale with which, without much effort or difficulty, you can make a high-quality connection that will not only look aesthetically pleasing, but will also minimize the likelihood of force majeure situations.

However, many still do not give up twisting due to the fact that all the necessary accessories are not always at hand, and the work needs to be done right at the moment, and for this method, in fact, only insulating tape is needed.

Moreover, this method is used not only by ordinary people, but also by electrical specialists when carrying out everyday work.

With the right approach, twists can last quite a long time without human intervention. But it is worth remembering that this approach is already a thing of the past and, if it is possible to connect using a terminal block or connectors, it is better to use this method, which in terms of safety and durability has significantly higher performance than twisting.

It is also worth remembering that twisting cannot be done if two wires of different metals are connected, as well as single-core and stranded wires. This is due to the fact that in fact they always have different resistance indicators, and accordingly, the reliability of operation with this approach will be extremely low.

Ways to twist wires

There are dozens of methods for connecting single-core and stranded wires by twisting. At the same time, you must always remember that the wires must not only be made of the same type of metal, but also the type of wire must be similar at both ends (if one of these conditions is not met, it is recommended to use connectors or terminals).

There are three types of twists, the difference between which is only the placement of the conductors among themselves:

In this case, both ends are placed next to each other.

This method involves placing the wires next to each other, after which they are secured to each other.

With this approach, the conductor is placed strictly perpendicular to the exposed part of the wire.

Twisting of stranded wires

The main condition for using twisting for wires with multiple cores is the maximum number of contacts with each other at the junction.

To do this, expose the ends of both wires and methodically twist each of them with separate connections to about a quarter of the stripped part and separate each treated pair with a whisk.

As a rule, in the end it is necessary to get two twists of wires to get plus and minus (zero and phase), however, in the case of grounding or one phase, there should be three of them.

• In order to connect the wires in series, bring them together into a bundle so that the rims have the maximum number of points of contact with each other, even at different angles. Then twist the wires on both sides, making one movement away from you, the second towards you, if you look at them in profile. As a result, some will be connected clockwise when viewed from the connection points.
• The parallel connection works in virtually the same way. The only difference is that the ends are brought towards each other at a slight angle until they intersect. After this, the plexus is woven into a single braid. In order for such a connection to last longer and be of higher quality, after the work done, the resulting twist must be filled with tin. If this is not possible, wrap insulating tape around it, in which case you should get at least two layers, or use special tubes.

Twisting wires in a junction box

In such a design, this type of connection is almost the only one, because it contains a fairly large number of wires of various sections and, as a rule, they are placed at a height, which does not allow high-quality use of welding or a soldering iron. There are three ways to perform distribution twisting. boxes:

1. Regular.
2. Bandage.
3. Twisting with a groove.

As a rule, the first method is used for domestic needs (in residential and utility rooms). If the work is done correctly and PPE caps are used, this connection method will last quite a long time without intervention.

Band twisting is usually used if the wires have a fairly large cross-section.

To ensure that the aluminum wires are securely fastened to each other, the bandage method is used.

It is recommended to use twisted wires in the junction box only if the cross-section is no more than 10 squares. In addition, if the diameter is up to 6 squares, the best option would be to use caps that will help securely secure the two ends together, and in terms of volume they will take up very little space.

Twisting wires in general can be called a reliable method if all actions are performed correctly. It is worth remembering that this approach to connection is not regulated in regulatory documents and in some situations it categorically cannot be used.

Source: http://jelektro.ru/jelektroprovodka/%D1%81%D0%BA%D1%80%D1%83%D1%82%D0%BA%D0%B0-%D0%BF%D1%80% D0%BE%D0%B2%D0%BE%D0%B4%D0%BE%D0%B2.html

Method of connecting electrical wiring: how to twist wires correctly

When installing electrical wiring, special attention is paid to electrical contacts, since the quality and reliability of the entire electrical network as a whole depends on this. An integral part of such contacts is the connection of wires. For this, both modern technologies and old methods are used. Each method has its own disadvantages and advantages. What type of wire twisting to use depends on the conditions and possibilities.

Requirements for twisting wires

Twisting wires together is the most popular and simplest method, but at the same time it is also the most unreliable. To understand how to twist wires correctly, you need to imagine what processes can take place at the junction. Over time, as a result of temperature exposure, the clamp weakens.

This is caused by linear expansion of the conductor during the passage of large amounts of current. The contact at the junction weakens, its resistance increases, and accordingly the twisted area heats up.

The wires oxidize and overheat, contact is lost or insulation breakdown occurs, which can lead to a short circuit and fire.

Requirements for twisting wires are regulated by the rules for installing electrical equipment (PUE). The basic rules for any method of connecting wires are to ensure contact without additional resistance. That is, this value at the place of twisting should not exceed the minimum value of the resistance of the wires themselves. This is also true for the requirements of mechanical strength; the contact point should not be less strong than the strength value of the wires themselves.

Therefore, according to the PUE, simply made connections in the form of twisting when installing electrical wiring are prohibited. After twisting, additional operations are required to increase its reliability. This can be soldering, welding, crimping, mechanical clamping.

It is important to note that twisting is applicable only if the connected conductors are made of the same material. Otherwise, a chemical compound is formed due to oxidation, which quickly destroys the twist.

There are different types of twists:

• parallel simple;
• sequential simple;
• parallel to the groove;
• consistent groove;
• bandage

Before starting the connection, you need to prepare the wires. To do this, you will need to remove the insulation over a length of at least 50 mm, clean the exposed wire with fine sandpaper, and only then start twisting. A parallel connection is used when there is a need to connect the ends of wires together, for example, in junction boxes. Consistent twisting when making branches.

Parallel connection method

Parallel connection is a simple operation that involves a method in which two wires, stripped to the same length, are applied parallel to each other. Next, the bare ends are crossed so that the edges touch each other. Then, with a rotational movement, they begin to twist. You need to twist in one direction, it doesn’t matter which way.

The insulated parts of the conductors must not be twisted together. First, the conductors are twisted by hand, forming a direction, and then tightened with pliers. In this case, the ends of the wires are taken with pliers to give the twisting uniformity.

The “parallel to the groove” method means that when twisting, one core is motionless, and the second braids it. To do this, starting from the end of the insulation, one wire makes three to four turns around the second.

We lay the first one with a tight touch parallel to the second one and at the end we perform three or four turns again.

Description of the sequential method

A simple serial connection is accomplished in a different way. The stripped ends of the wires are not applied to each other, but are arranged oppositely, overlapping. The middles of the stripped strands are applied to each other, and then braided in one direction and the other. In this case, it is necessary that the stripped conductors do not come into contact with the insulation of the opposite wire. When twisting with a groove, each core is braided with the other only at the end of the insulation, and in the middle it passes with a tight touch.

Cable banding

It is performed using both parallel and sequential methods. In the first method, the wires are pressed against each other with an insulating layer, and a third conductor is wound around the stripped conductors in a spiral motion.

To do this, one end of the additional wire is held with your fingers, and the other is wrapped around with pliers, tightly squeezing the connected wires together.

In the second method, the stripped wires are applied in parallel, but opposite each other, not reaching one or two millimeters from the insulation of the opposite wire. Then they are tightly rolled with an additional conductor.

Twisting a multi-core cable

There are some minor nuances with this connection. To increase the contact area, the same methods are used, but with preliminary separation of the cores in each wire.

After removing the insulation, the conductors are separated in each wire, and two to four pigtails are created from them with an equal number of conductors in each. Then they are laid one on top of the other, and the wires are twisted, one pigtail from each wire. At the end, the resulting braids are woven together.

This way you will get the correct twist of the wires with strong mechanical strength and low resistance.

The number of turns that is obtained during operation should be more than six. The types of wire connections do not depend on the material used and are performed in the same way for both aluminum and copper wire. It is important to understand that you cannot twist different types of wires together, and the aluminum wire may break if twisted excessively. If you need to twist more than two wires, the process technology will not change.

Additional technological operations

Since the PUE prohibits twisting alone, and it is impossible to connect different materials, the twisting process must end with a terminal block or soldering. To make the connection reliable, the following technological operations are used:

• soldering;
• welding;
• screw terminals;
• crimping in special spring devices;
• crimping.

Soldering and welding when connecting

The only drawback of this operation is the labor intensity of the work. To perform soldering you will need tin and flux.

When working with copper, rosin is used as a flux, while for aluminum, highly active fluxes containing oleic acid and lithium iodide are used.

If a soldering iron with a power of up to 100 W is enough for soldering copper, then aluminum is welded using a gas heater, the heating temperature should be 400-500 degrees. Solder for copper is lead-tin. And for aluminum containing zinc.

The technology itself is simple, since the thermal conductivity of twisting is greater than that of solder, when melted it transfers to the joint, creating a thin layer. When soldering, large amounts of solder are not allowed; it should be distributed evenly over the entire surface.

Application of screw terminals

Screw clamps, in their operating principle, involve mechanical compression of twisted surfaces using a bolted connection. For this, steel pads are used. The finished twist or individual wire strands are placed under a steel washer and compressed by screwing in a screw. In this case, the clamping is carried out both by the washer itself and only by the screw. The first method is better, since the contact surface is larger.

The terminal block itself looks like a plate on an insulator with a group of contacts. Using terminal blocks, both copper and aluminum wires of different sections are connected.

Using spring devices

Allows for the fastest connections without the use of tools. Wago terminal blocks are widely used. They are produced not only in different sizes, but also for different numbers of connected wires.

With their help, single-core and multi-core wires of different sections and types are connected. The wires are combined both individually and with each other. For this purpose, the terminal blocks have a latch-flag, which allows you to lay the wire and clamp it inside after latching.

Or use a device in the form of clips.

Using the Wago terminal, you can connect aluminum and copper to each other. But for this, a special paste is used to prevent air from entering, and the wire strands are separated into separate cells.

Crimping of connected cords

If it is necessary to connect large cross-section wires, lugs (sleeves) are used. The wires are stripped and inserted into the sleeves, then the sleeve is compressed using press pliers and the wire is crimped. This connection is considered reliable, but requires specialized tools.

Connecting insulating clamps (PPE) are also considered a kind of crimping. After twisting the wire, depending on the diameter, the caps are screwed on top of the connection, pressing the contact and insulating it.

The last final step after making the connection is to carefully isolate it. Dielectric tape or thermal tube is used as an insulator. The insulation should be 2-3 cm larger than the junction itself. The insulation must be carried out efficiently, otherwise there is a possibility of a breakdown between the wires, which will lead to a short circuit.

Source: https://obrabotkametalla.info/elektrik/pravilnaya-skrutka-elektricheskix-provodov

Twisting wires correctly, different ways to twist wires

Safe operation of the electrical network depends on whether the wires are twisted correctly and whether the peculiarities of connections between copper and aluminum cables are taken into account. It is necessary to take into account the cross-section and number of wires in the wires. Basic knowledge of the basic principles of cable splicing is the key to high-quality electrical network installation work.

It is important to know and apply, but why?

Electric current is a source of increased danger. Neglecting the rules for installing an electrical network can lead to the following consequences:

• electric shock;
• poisoning from toxic smoke from burning insulation;
• fire.

Poor quality twisting is one of the reasons for such consequences. In places of poor connection, the passing current experiences increased resistance. The resulting thermal energy does not have time to dissipate and excessive heating occurs. As the load increases in this section of the circuit, the resistance increases even more and a short circuit occurs.

Twisted connections made in accordance with the rules guarantee safe operation of the network. At the point of contact, resistance will not increase; current will flow through the conductor. Connected electrical wires can be hidden in a box or under plaster. There will be no consequences if you follow the twisting instructions.

Basic methods

Wires made of the same metal, for example copper wires, can be twisted together directly. The most common are the following:

• simple twist;
• bandage;
• twisting with a groove.

The simple correct twisting of electrical wires is known to every electrician who has once connected them with his own hands. For two cores with a cross section of more than 4 square meters. mm. you need a bandage method, in which you tie it with a third wire. Trough twisting is a method of connecting aluminum wires when the ends are bent with a hook, re-hooked and wrapped.

When connecting copper and aluminum, which have different resistances, an additional conductor is required. This could be a brass tube, a connector block, or a slip-on terminal. Threaded connections are also used with the obligatory use of additional slotted washers. In such connections, it is necessary to increase the contact area, which is achieved by flattening the cores and reducing the resistance of the passing current.

Modern materials

Manufacturers of electrical installations offer their solutions to the issue of connecting wires. Factory-made compact connectors are a modern alternative to twisted cables. For example, PPE clamps for twisting are a cone-shaped spring installed in a dielectric housing. The caps and bundles of wires inserted into such PPE are twisted several turns and securely fixed.

For quick connections, “Wago” terminals from the same manufacturer are suitable. The joint in them occurs automatically: when the core is inserted into the corresponding hole, a flat-spring clamp is triggered. Such terminals can be disposable or reusable. Due to ease of use, wiring is easy and contact is reliable.

Don't forget the standard terminal blocks, which are universal for all types of connections. Made using a block, the connection is as good as either Wago or PPE caps.

One-piece crimping

For twisting stranded wires, special permanent crimp connections are used. This connection method should be used for identical metals, since due to the difference in resistance in each crimp, contact, for example, of copper with aluminum will lead to heating. If the twist is made of copper wires, this should also be the connecting tube, the diameter of which approximately corresponds to the thickness of the connected wires. Pre-twisting of the wires is not necessary.

The cables inserted into the tube are crimped with press pliers on both sides. At least three layers of insulating material are applied to the resulting joint. As an alternative to insulating tape, you can use ready-made crimps with an insulating cap. Such a tube is crimped immediately with a polyethylene cap, which gently deforms and reliably isolates the joint.

Advice: before twisting the wires, it is necessary to calculate the load on the electrical network. To do this, the power of all electrical installations that can operate simultaneously is summed up. The minimum cross-section of one of the connected cables must correspond to the design load.

What about the larger cross-section?

Use of standard connection options for conductors with a cross-section of 10 mm. sq. and is no longer allowed. In such cases, the ends of the cable are compressed with a special tip, on the sides of which there is a sleeve and a ring. One or more twisted wires are inserted into the sleeve and crimped with press pliers such as PC, PMK, PKG or PC. The lug ring is designed to connect to the terminal or pad of another wire.

As a rule, connections through a tip with a ring are used to connect the contact wire in power panels. In such installations, it is not allowed to simply twist the wires together, because high voltage will instantly burn the wires at the joints.

Soldering iron to help

In addition to twisting, soldering is used at the joints. This method is used in places of high humidity, where the requirements for resistance of wires to oxidation are most important. The pre-made twist is melted with rosin, after which solder is applied to it. At the same time, the power of a regular household soldering iron is sufficient; it is important to prevent the formation of sharp burrs on the solder. After drying, they are removed with a file, because there is a risk of damage to the insulation.

The use of solder helps to connect thin stranded wires that are twisted together. The contact surface after processing with a soldering iron increases, therefore, the contact area of ​​the connections becomes larger. It is worth considering that the load on the connected wires, regardless of the use of soldering, is calculated based on the cross-section of the smallest of them.

Original solutions

It is not necessary for everyone to know how to make the correct twist using non-standard solutions, but in some cases it is precisely this knowledge that helps to cope with the work. For example, how to properly make a twist in which it is necessary to connect not two or three wires, but several dozen pairs? For this purpose, a special mechanical device is used - manual press equipment. This press twists both stranded and single-core wires of the same metal.

Sometimes, on the contrary, it is necessary to decide how to properly twist for low-current installations: power cords, LEDs, telephones, etc. For this, special connectors are used, which are plastic caps for twisting wires, inside of which there is a metal alloy plate in a special solution. This is a hydrophobic gel that prevents rust and protects the contact from oxidation and moisture.

Source: https://vseobelektrike.com/elektroprovodka/montazh-elektroprovodki/skrutka-provodov-pravilno.html

How to twist wires? Connection of copper cables

Before performing the twisting procedure, it is necessary to strip 5-7 cm and try not to damage either the core or the insulation.

This can be achieved using a stripper, or very careful work with a repair knife or a stationery knife. Damage to the core will increase the chance of wire breakage and reduce the contact area.

Learn more about electrical contacts. on the roughness of materials and the dependence of resistance on the contact area, you can read the article on our website - “Electrical contact“.

Twisting is done by clamping the conductors from the insulation side with pliers, and on the other side we firmly clamp them with second pliers, thin-nose pliers and twist them with a slight pull away from ourselves. This force is required to ensure that the conductors twist evenly and do not come out in different directions.

If the force is insufficient (photo above), the coils will come out along the entire length, especially at the base. All this leads to deterioration of contact, and this in turn to overheating and, in the worst case, to “burning out”.

Already better than 60% of electricians, but not enough.

The turns of a good and high-quality twist should be as close to each other as possible, as shown in the photo at the very beginning. There is no limit to perfection, but do not overdo it with force, otherwise they may simply fall off.

The length of a more or less good twist should be at least 5-7 centimeters.

Serial connection of wires by twisting

This type of twisting may be required when a wire breaks, reconnecting wires in a junction box, when there may not be enough conductor for a full twist. or the supply is very small.

In this type of twisting, the only emphasis is on strong twisting, so that there are as many points of contact with the conductor as possible. It should fit the surface of the other wire as much as possible.

The minimum number of high-quality turns is 5-7 for each conductor.

Branch

• How to clamp - option 1
• How to clamp - option 2

You need to clamp the main conductor with pliers, and on the side, closer to the edge of the lip, the branch wire, and squeeze it tightly. As in the previous method, the wound turns should fit tightly.

Since in this case only one conductor is wound, then there should be 2 times more turns than with sequential twisting, that is, at least 10-15 turns.

When branching and connecting wires in series by twisting, it is better to tighten the turns with pliers for better contact. And also tin the entire twist afterwards.

And the twist with electrical tape

It is believed that only insulation applied in three layers will be approximately equal in its insulating qualities to the factory one. Therefore, when insulating tape is wound onto a twist, each new layer covers half of the previous one.

When applied, the electrical tape is also slightly stretched so that it fits snugly against the conductor.

The application of insulation begins and ends by stepping back 1 centimeter from the bare conductor to the factory insulation.

Source: https://electricity220.ru/scrytki/