Is it possible to connect wires of different sections - how can you reliably connect copper wires of different sections
How to connect wires of different sections?
In private construction, sooner or later the need to install electrical networks arises. Some people turn to specialists for help, others want to do it themselves. The process itself is not very difficult if you have certain skills and knowledge of safety standards, but this mainly concerns the connection of wires of the same cross-section.
But quite often situations arise when it is necessary to reliably connect three or more wires to each other, and they all have different cross-sections. In this regard, the question of how to correctly and safely connect wires of different sections is currently one of the most pressing when installing electrical networks.
Methods for connecting wires of different sections
Connecting copper wires of different thicknesses is not the most difficult process. However, for maximum reliability and safety, certain requirements must be observed here. There are several ways to connect three wires of different cross-sections:
- welding or soldering;
- using screw clamps;
- using self-clamping terminals;
- bolted connection;
- branch compression;
- using copper tips.
Three wires of different cross-sections can be reliably connected using any of the listed methods, but it is important to remember that when installing sockets and switches, cables of different thicknesses cannot be connected to one contact. In this case, the thinnest one will not be pressed tightly enough. And this, in turn, can negatively affect operational safety.
Connecting wires of different sections by welding or soldering
The simplest, but fairly reliable way to connect cables that have different thicknesses. In this case, three wires can be connected to each other using rigid twisting and subsequent fixation. But here it should be remembered that a reliable connection is only possible between wires of approximately the same cross-section. Twisting of wires whose diameters differ significantly cannot be reliable.
You need to carefully twist three wires of different sections together. Each copper wire should tightly wrap around the adjacent one. The gaps between them should be minimal. Otherwise, this will affect the safety of subsequent operation.
Before you begin directly twisting the three wires, lay them out in front of you and sort them by thickness. You cannot wind a thin wire onto a thick one - this will affect the quality of the contact. Such a connection will not last long.
Connecting three wires of different sections using screw terminals
Three wires of different thicknesses can be reliably connected to each other using special ZVI screw clamps. The clamps have a very convenient design and allow you to create contact between cables that have different cross-sections. The strength of the connection is achieved by using separate screws for each clamp.
You need to select ZVI clamps taking into account the cross-section of the wires that will be connected, as well as their current load. For reliable contact, it is recommended to connect three wires of adjacent sections. Let us conventionally designate the cross-section of the connected conductors as SPP, and the permissible long-term current as DDT. Below are the parameters of clamps and wires:
- ZVI-3 – SPP 1 – 2.5; DDT – 3;
- ZVI-5 – SPP 1.5 – 4; DDT – 5;
- ZVI-10 – SPP 2.5 – 6; DDT - 10;
- ZVI-15 – SPP 4 – 10; DDT - 15;
- ZVI-20 – SPP 4 – 10; DDT - 20;
- ZVI-30 – SPP 6 – 16; DDT - 30;
- ZVI-60 – SPP 6 – 16; DDT - 60;
- ZVI-80 – SPP 10 – 25; DDT - 80;
- ZVI-100 – SPP 10 – 25; DDT - 100;
- ZVI-150 – SPP 16 – 35; DDT - 150.
With the right choice of screw clamp, you can create a truly reliable connection that will ensure uninterrupted operation of the electrical network.
Connect wires of different sections using bolts
Another way to connect wires of different sections to each other is to create contact using bolts, washers and nuts. According to professional electricians, this connection is the most durable and strong. The process itself is not too complicated and takes minimal time. The procedure goes as follows:
- the copper conductors of the wire are carefully stripped (the length of the stripped section of the conductor depends on the diameter of the bolt);
- the stripped core is bent into a loop;
- the loop is put on the bolt;
- an intermediate washer is installed on top;
- then a loop of wire of a different cross-section is put on and secured with an intermediate washer.
This continues until all the wires are connected to each other. After putting on the last loop and the last washer, the structure is firmly tightened with a nut.
Using copper lugs for contact connections
Another very simple way to create a reliable connection is to use copper lugs. They are recommended to be used for contacting large diameter wires. Before starting the procedure, it is necessary to prepare not only the tips themselves, but also special equipment - crimping pliers or a hydraulic press.
Despite all the obvious advantages, this type of connection has one (but significant) drawback - it is quite large in size, due to which the resulting structure may not fit into every junction box. Nevertheless, specialists actively use this method.
The process of creating a contact is as follows:
- wires of different sections are carefully straightened;
- the veins of each of them are stripped to about two to three centimeters;
- a tip is put on each stripped core and clamped using a hydraulic press or crimping pliers;
- Then the bolts are put on, and the wires are connected with a nut.
After all the work is done, you need to carefully isolate the connection point so that no dangerous situations arise during operation.
Do-it-yourself electrical wiring and creating contacts using terminals
Universal clamp terminals appeared on the market relatively recently, but almost immediately began to be in serious demand not only among specialists, but also among potential clients who prefer to carry out all electrical work at home themselves.
Using self-clamping terminals, you can create strong and reliable contacts between several wires ( three or more ). The main advantage of such terminal blocks is their almost unlimited functionality - they can be used to connect wires whose sizes vary significantly.
The design of the terminals provides for the presence of holes into which pre-stripped conductors are inserted. For example, you can insert a wire with a cross-section of 1.5 mm into one hole, a wire with a diameter of 4 mm into another, a wire with a diameter of 4 mm into the third, and so on. And after connecting them, the contact will be quite strong and reliable.
There are several other ways to connect three or more wires of different diameters, but they are used quite rarely due to the complexity and duration of the process itself. If you want to use one of them, first consult with a specialist who is competent in this area.
Source: https://remont.youdo.com/articles/electric/soedinit-raznie-provoda/
Correct twisting: features and types of connection of electrical wires
Perhaps the most cherished dream of any electrician is electrical wiring without intermediate breaks. So that a separate wire passes from the panel to each switch or socket without connections. But this is a pipe dream - not many people will like the fact that dozens of wires will be connected to the electrical panel. And it gets expensive - you need a lot of wire. That's why the wires branch and connect.
Typical wiring in an apartment can have over a hundred connections. And electrical wiring faults, as a rule, appear precisely in these connections. Therefore, great attention must be paid to the correct connection of wires.
Wire connection methods
methods are used to connect wires :
- pressing (crimping);
- twist;
- PPE clips;
- screw terminals;
- welding;
- soldering;
- bolted connections;
- WAGO terminals.
What is better to choose for twisting wires?
To begin with, let's turn to the PUE. Paragraph 2.121 says that correct termination, branching and connection of cable cores and wires must be carried out using soldering, welding, pressing or clamping (bolt, screw, etc.). That is, of all the above options, only twisting is illegal. But twists will exist until the day there is electricity. Therefore, we will tell you about all connection options.
Twist
Despite the contradiction of the PUE, twisting is considered the most popular type of connecting wires. The main disadvantage of twisting is the gradual weakening of the fastening due to residual elastic deformation of the cable core. Moreover, the transition resistance in the twist increases, the cable begins to overheat and the connection is broken. It's good if there is no fire.
But a properly made twist can last a very long time without any cause for concern. Therefore, if other connection options are not available to you, then twisting can be done at home. But only high quality!
Important! This option should only be used as a last resort. If possible, use other options.
- Do not twist when the current in the circuit is more than 2-3 Amps.
- Do not twist when laying wires over flammable materials.
- Do not accept work from electricians if the connections are made by twisting without welding or soldering.
- Do not use twists if you are engaged in electrical work as part of an individual business or official duties - this will entail liability, possibly even criminal liability.
wires made of different materials (aluminum and copper), as well as multi-core and single-core cables in one twist For high-quality twisting, the insulation is removed from two cables to a length of 70–90 mm, the wires are laid perpendicularly crosswise and twisted. If the cable diameter is small (up to one sq. mm), then this can be done manually. But it is advisable to twist it with pliers. The coils must be tight.
The remaining edges of the cable (4-6 mm) are removed with pliers using a screw rotation, while the cable material seems to be smeared together. When attaching three or more wires, the freed ends from the insulation are laid together, parallel to each other, as tightly as possible and twisted by the ends with pliers. After this, the remaining ends are bitten off in the same way. The total twist size must be at least 12–14 diameters of the twisted wires.
Then you need to insulate the twist. To do this, use insulating tape, heat-shrink or polyvinyl chloride tubing, or special caps. It is advisable to thread the heat shrink tube twice, and wind the insulating tape in at least four layers. The insulating material must capture all intact cable insulation - this will protect the twist from moisture and prevent slipping.
Soldering
This is the most labor-intensive option for connecting wires, which requires some experience. Better quality twisting than poor soldering. Therefore, we will provide general information to those who have sufficient skills.
Before soldering, the cable is cleaned of oxides; if necessary, it is tinned, screwed (maybe not as tightly as when twisted), treated with flux and soldered. You can solder both aluminum and copper wires if you choose the right solder and flux.
There is no need to choose an acidic active flux - it will certainly remain on the wires and will destroy the connection over time. Soldering takes quite a lot of time, but the fastening is one of the most reliable.
Welding
The most durable option for twisting wires. Even with little experience, this connection option is relatively quick and simple. Welding is done with a current of any polarity with a voltage of 12-35 V. It is best to have the ability to regulate the welding current. For welding two copper wires with a diameter of 1.5 square meters.
mm 70 Amperes are enough, for 3 wires the voltage increases to 85-95 Amperes, for 3 wires 2.5 kW. mm, 95-110 Amperes are required, and 4-5 of these wires already require 110-130 Amps. With the correct current for welding, the electrode does not stick and the arc is kept quite stable.
Copper-carbon electrodes are used to connect copper conductors.
Insulation 60-70 mm long is removed from the wires and connected “for welding”. It differs from simple twisting in that the ends of the cores are not twisted by 6-7 mm. They are straightened and clamped parallel to each other. If three or more wires are screwed in, then there should still be only two wires at the end, the rest are cut to the length of the twist. This makes it easier for a melt bead to form when the welder is weak.
Important! Welding work must be carried out in compliance with all fire and electrical safety rules with the mandatory use of protective equipment (glasses with a thick filter or a welding mask, gloves, protective clothing).
Then the twist is placed in a welding clamp and the weld is made with an electrode. During welding, you need to melt the ends of the wires until a melt ball appears. For strong mechanical and electrical contact, the melting point must reach the main twisting area. After cooling, the wires are insulated in a way convenient for you.
For welding wires, you can choose different types of welding machines. inverter-type welding devices . Their advantages:
- have low electricity consumption;
- low weight and dimensions;
- large range of welding current regulation;
- provide a stable welding arc.
So, with a fairly large number of electrical installation works, purchasing a welding inverter can be considered the best choice; this device will be useful in many other works.
PPE connection
This is a plastic cap with a square metal wire inside, installed in a spiral cone. Often its cavity is filled with a special lubricant that protects the wires from moisture and prevents oxidation. When connecting wires using PPE, it is important to choose the size of the clamp correctly, taking into account the number and diameter of the wires being connected. As a rule, this information is located on the packaging.
For fastening, the insulation is removed from the wires to a size slightly smaller than the length of the cap, laid together and the PPE is screwed on top. Moreover, the edges of the square spring remove the layer of oxides from the surface of the core, its cone moves apart and, thanks to its elasticity, reliably clamps the wires together. For reliability, some electricians prefer to first do the usual twisting and then install the PPE.
The advantage of PPE is the simultaneous fastening of wires and insulation of their connection area. Disadvantages include weakening of the spring over time, which leads to increased contact resistance. It is not advisable to install PPE in high-current circuits.
Screw terminals
This fastening is very widely used when connecting switches, electrical sockets, lighting devices and other electrical fittings to wires. Screw clamps are often used when assembling electrical panels , as they make it possible to carry out neat and quick installation.
The obvious advantages of clamps include the absence of the need to isolate the fastening. Using these clamps, you can fasten wires made of various metals (copper and aluminum).
Of course, there are also disadvantages. It is not possible to install a multi-core cable into the clamps - it must first be crimped or soldered. In addition, screw terminals require maintenance - they need to be tightened from time to time to prevent the connection from loosening. In general, if there is a free approach to the connection areas, then screw terminals are an inexpensive and reliable solution.
WAGO terminals
This fairly new type of fastening is based on the installation of insulated spring clamps manufactured by the German company WAGO. These WAGO connectors are manufactured in a large assortment and include connectors of various designs, for various purposes, for a wide variety of cross-sections, types and numbers of wires. Therefore, it is advisable to buy WAGO connectors in a specialized store and always check the certificates.
The main advantages of these connectors include quick and easy installation without any special devices, as well as simultaneous insulation of the connection and fastening of the wires.
WAGO fasteners have all the necessary tests, are certified and are widely used both in our country and around the world. Therefore, there are no serious reasons not to trust them. All cases of any problems are due to the wrong choice of WAGO fastening for a certain load or the installation of fakes. It is these points that you need to pay great attention to when using for connection.
Crimping
This option means connecting the wires using crimping with a lug or tubular sleeve. Tips and sleeves are made for cables and wires with a core diameter of 2.6-250 square meters. mm.
Crimping is quite convenient for “set and forget” fastenings, but requires special equipment and the correct selection of sleeves for the specific diameter and number of wires being fastened.
The tools used are crimping presses, as well as manual hydraulic, electric and mechanical pliers.
For crimping, select the required sleeve; if necessary, adjust or select the working end of the tool. The insulation is removed from the wires, the conductors are cleaned and lubricated with a special paste, the sleeve is put on and clamped. A high-quality tool clamps the entire length of the sleeve in one pass; cheaper ones require several clamps at a certain distance from each other. After this, the sleeves are insulated with heat-shrinkable tubing or insulating tape.
Bolt fastenings
Used in circuits with high voltage . A washer of the required diameter is placed on the bolt, then the wires are wrapped around the bolt, another washer is put on and the whole thing is carefully clamped with a nut. If you install an additional metal washer between the cores, you can connect copper and aluminum wires together. In residential electrical wiring, this option is almost never used due to its bulkiness.
All completed installation connections of any type must be accessible for further maintenance and inspection. Correctly selected connection of wires is the main guarantee of the reliability of electrical wiring in an apartment or private house.
Source: https://stanok.guru/oborudovanie/raznoe/pravilnaya-skrutka-i-vidy-soedineniya-elektricheskih-provodov.html
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
Correct twisting of 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://uelektrika.ru/soedinenie-yelektroprovodki/pravilnaya-skrutka-provodov/
How to twist wires together
» Electrical wiring » Wires and cables » How to twist wires together
Every person who has dealt with wiring knows how important wire twisting is. At first glance, it may seem that there is nothing complicated about this; I twisted two wires together, insulated them and that’s it.
But there are some features that should be taken into account. After all, if you do anything wrong, you risk your property and the health of your loved ones, because this can lead to a fire.
In this article you will find all the basic tips and methods that will help answer the question: How to twist wires correctly.
Why incorrect twisting is dangerous
Twisting all the wires together is a fairly popular method, but at the same time it is the most dangerous. After all, if you bend all the wires weakly, after a while they may weaken, and a weak contact will appear in this place. This will lead to the fact that when voltage comes into the cable or the wire overheats, the result in this case is the same - a short circuit or electric shock to a person.
It’s not for nothing that this method is prohibited in the PUE, although many experienced electricians use it.
But, I don’t want to scare you so much, if the wires are twisted together correctly, nothing will happen, and they will serve you all the time. To do this, read our basic methods. I would like to note that the ABS cable has features, find out about them.
Instructions for twisting wires
Initially, we will talk about the simplest method, when you need to twist two single-core wires together if they have the same metal.
- We strip the cores together, 4-5 cm is enough.
- The contacts need to be degreased; you can take a rag soaked in acetone.
- We sand everything down to a metallic color.
- We cross the conductors with each other, wind one of them onto the other using pliers. The minimum is five turns.
- The second one is wound by 5-7 turns.
- We isolate everything. Under no circumstances should you allow the bare cable to stick out.
Now let's talk about how to twist single-core and stranded wire. We use the first two steps from the instructions above. Next, we must cross the two wires with each other, winding the stranded wire on the middle of the single-core wire, the distance is 2.5 cm from the end. When all the branches have been twisted together, bend the free end using pliers. How to do this, see the photo below.
This method is also suitable for cases when you need to twist two stranded wires together. The twisting of 3 wires occurs in the same way, as it looks like in the picture below. In this way you can twist the VVG wire.
Twisting three wires
Twisting wires video
Also look at the device for twisting wires together, it can be done without much effort. How, watch this video.
Tips from All-Electricity on twisting wires
Here you will find basic tips to help you twist wires together safely. We highly recommend using them.
- It is better to connect the twist by soldering or welding.
- WAGO terminals can be used. With their help, everything can be done faster and safer.
- PPE clips. They increase the reliability of the connection and are inexpensive.
- After twisting the cables, turn on the electrical circuit and wait a few minutes (preferably half an hour). If it gets hot, it means you did something wrong. It will need to be redone.
So we have looked at all the main ways of twisting wires and cables together. There is nothing complicated, but all recommendations must be followed.
Recommended reading: Ideas on how to hide wires.
Source: https://vse-elektrichestvo.ru/elektroprovodka/provoda-i-kabelya/skrutka-provodov.html
How many wires can be twisted into one twist?
Currently, simple twisting of wires as a type of electrical connection is prohibited. But at the same time, it is often used for greater reliability of contact in other connection options, for example when welding conductors.
Previously, I already talked about all the permitted methods of connecting wires when installing electrical wiring. For a truly reliable and durable connection that will pass any test, be sure to choose one of these.
Now I will tell you in more detail about how many wires can be twisted together . Moreover, you will learn a simple rule, following which you can easily determine the required number of wires of any cross-section for twisting .
And, if you wish, you can twist at least 50 cores together, but I highly do not recommend doing this, now I’ll tell you why.
Many professional electricians will tell you literally the following: “ Correct twisting of copper wires when laying electrical wiring is in itself quite reliable without the use of additional clamps, welding, terminal blocks or sleeves .”
And you will definitely hear stories from practice when a distribution box is opened in an apartment that is several decades old, and the connections there are made through ordinary twists. At the same time, they, like the rest of the electrical wiring, are in close to ideal condition.
There is a simple explanation for this - correct twisting of wires implies their uniform laying, with the required force, of sufficient length, using the correct insulation , etc.
All this together gives a reliable, long-lasting contact that does not require additional revisions for broaching.
As you understand, to do professional twisting of cable cores, you need certain experience and skills. Violation of technology leads to poor contact. Such a connection is simply dangerous; it can heat up and be a source of fire.
That is why it was decided to prohibit all twists when connecting wires. Other methods are much easier to control and forgive some errors during installation. This increases overall electrical safety.
For the same reason, there is a limit on the number of wires that can be twisted into one twist . It is almost impossible to achieve high-quality twisting of a large number of wire strands without experience.
How many wires should be in a twist?
Most often, it is recommended to collect no more than 6 cores with a cross section of 2.5 mm2. in one twist , or better, especially if you have little experience, no more than 4 times. Cables with this cross-section are used in apartments for socket groups.
You can take more conductors with a cross section of 1.5 mm2 used for lighting. And the cables going to the electric stove have a conductor cross-section of 6 mm sq. As you understand, even six pieces are very difficult to neatly twist together without experience.
In order not to memorize the maximum number of wires recommended for twisting:
There is a simple rule:
The total cross-section of all wires in a twist should not exceed 16 mm2, and the total number of wires is 6 pieces
Standard distribution boxes most often have up to 6 cable entry points, so twisting with a large number of conductors usually does not work.
Another simple explanation for the limitation of the maximum number of cores is the following: a larger number simply will not allow the tool to properly grasp them when working.
Therefore, I recommend not twisting more than 6 wires at the same time. But, with some skill and strong hands, or using various devices, in rare cases you can twist up to 8 pieces.
Below is a table showing the recommended maximum number of wires in one twist for different cable sections:
Wire cross-section mm.kv | Number of wires in twist | |
Recommended | Maximum | |
1.5 | 6 | 8 |
2.5 | 4 | 6 |
4 | 3 | 4 |
6 | 2 | 2 |
10 | 2 | 2 |
When making electrical installations, try to avoid cases where it is necessary to twist more wires than are recommended here.
It is always better to make an additional junction box than to get a poor-quality connection, which will then cause you a lot of problems.
And once again I would like to remind you that officially, simple twisting in electrical applications is prohibited and is used only in combination with other connection methods - compression, welding, etc.
I am sure that there are a lot of people who will say that they can easily twist a larger number of wires with high quality, and the resulting connection is as reliable as possible. I won’t argue with this; moreover, in my practice I’ve had to do something like this (I always weld conductors after twisting).
A striking example of this could be an article about extending the input cable to an apartment, where 3 wires of 6 mm square were twisted. When using certain technologies, this is possible, but I do not recommend doing this all the time; use this opportunity only as an exception.
What do you think? Tell us about your experience in installing twists and the maximum number of wires that can be done efficiently. I am especially interested in the opinion of novice electricians who have decided to do wiring in an apartment or country house.
Source: https://RozetkaOnline.ru/poleznie-stati-o-rozetkah-i-vikluchateliah/item/222-ckolko-provodov-mozhno-skruchivat-v-odnu-skrutku
How to twist wires correctly
When laying wiring in the house, you cannot do without connecting the wires. After all, a network with branches is laid around the house to power certain electrical appliances.
The need for wiring connections
Distribution boxes are used to branch the electrical network. But they are intended only to hide the connections of power network branches.
The need for wiring connections is found everywhere. They connect wiring in different ways in the house, electrical appliances, cars, in general, wherever there are wires.
Nowadays, several methods of connecting wiring are used. Each of them has its own positive and negative qualities.
The most common ways are:
- Twisting;
- Soldering;
- Welding;
- Use of terminal blocks, blocks;
- Use of self-clamping terminal blocks;
- Use of connecting insulating clips (PPE caps).
Terminal blocks and blocks
But the use of terminal blocks and blocks is a completely separate way of connecting wires.
The terminal block and block are a small metal plate with contacts on the edges.
This plate is encased in insulating plastic. Bolts are often used to clamp wires.
The difference between a terminal block and a block comes down to the fact that the terminal block allows you to connect only two wires, while the block is designed for several connections.
Simply put, a block is several terminal strips connected together to provide several separate connections.
To connect two wires, it is enough to clean their ends of insulation, and you don’t need to clean much, 0.5 cm is enough, it is only important that the cleaned end reaches the contact.
In this case, the bare wire should not protrude beyond the edges of the terminal block, in order to avoid accidental contact with it.
Next, the bolt is clamped with a screwdriver, ensuring reliable contact of the wire with the plate.
On the other side of the terminal block, the other end of the wire is fixed. The metal plate will act as a bridge between them.
When using a terminal block, they connect only two wires; for subsequent ones, another terminal block is used.
The block allows you to provide several connections, which, with a large number of wires, will result in more compact dimensions.
Terminal blocks and blocks are good because they allow you to connect together wiring made of different metals and differing in cross-section.
In addition, they are detachable, so you can disconnect the desired wire at any time. They are good for both single-core and stranded wires.
Their disadvantages include the increased dimensions of the connection, especially for the pads.
Hiding terminal blocks and strips can be very difficult. In addition, ordinary terminal blocks will not allow insertion into the wiring; twisting allows this. But about the sidebar - a little lower.
READ ON THE TOPIC: What are NShVI lugs for crimping wires.
Self-clamping terminal blocks
Self-clamping terminal blocks are a type of conventional terminal blocks. They provide an even faster connection because you don't even need to use a screwdriver.
The contacts in them are spring-loaded, so to connect the cables it is enough to insert the ends of the wires into the holes with the contacts.
During installation, you need to overcome the force of the spring, after which it will press the contact to the wire. It is noted that this method is very convenient for multi-core wires.
Among the disadvantages of such a connection is that the connection is not particularly reliable; it will not be difficult to pull out the wiring from the terminal block. This is especially true for single-core wires with a large cross-section.
A common disadvantage of terminal blocks is the possibility of moisture getting on the contacts, which can lead to their oxidation and disruption of the connection.
PPE caps
PPE caps are a simple and convenient way to connect. They are produced in three types - without contacts, as well as with clamping and spring-loaded contacts.
Caps without contacts are made only of insulating material. They are intended for insulating twists.
They are placed on top of the twist, protecting it from moisture.
Caps provide easy access to the junction of wires and are often used in junction boxes.
In caps with a clamping contact, a ring of soft metal is installed inside. Such a cap is put on the twist, and for a better connection, the installed ring is compressed with pliers.
This cap can also be used as a separate connection, without preliminary twisting.
The wires, stripped of insulation, are inserted into the cap ring, after which it is clamped with pliers. These caps provide a virtually permanent connection.
Caps with a spring contact work identically to those described, but they do not need to be clamped; the spring inside will ensure secure fastening. This cap has a detachable connection.
Wire insertion
At the end, a few words about the sidebar. Most often, twisting is used for such a connection.
On the wire to which you want to connect another wire, a small area is cleared of insulation. The stripped end of the connected wire is wound onto the cleaned area, after which everything is insulated with electrical tape.
It is possible to use a special terminal block for insertion. It is T-shaped and consists of two halves with a plate inserted in them.
Such a terminal block in two halves encloses the cleaned area to which the insertion will be made. And the wire that needs to be powered is connected to the side tap of this terminal block.
All types of electrical network connections used were discussed here.
And although the electrical network has been used for a long time, the best connection of two wires is still ordinary twisting, perhaps in addition reinforced by soldering or welding.
Source: https://ElektrikExpert.ru/kak-pravilno-skruchivat-provoda.html
How to twist wires correctly: instructions, diagrams, videos
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:
- Carefully strip both wires using a special tool or a simple knife, removing the insulation by about five centimeters;
- Degrease bare contacts with acetone;
- Take a piece of sandpaper and sand the ends of the conductors to a pronounced metallic color;
- 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);
- We wind the second core in the same way;
- 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:
- 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.
- 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.
- 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.
- 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: http://elektro-enot.ru/kak-pravilno-sdelat-skrutku-provodov/
Twisting wires - how to do it correctly
We will not prove to you that twisting wires is a good connection method. Yes, it can be done well and insulated. It is also perfect as a temporary option.
But according to the rules of electrical installations (PUE) in order to connect a wire or cable, ordinary twists are not recommended. Nevertheless, we will talk about it, and in very detail. Firstly, because, contrary to the PUE, most connections are made using this ancient “old-fashioned” method.
Secondly, because correct twisting is the main stage of the most reliable methods of connecting wires - welding and soldering.
Why do you need a good twist?
Imagine that the two wires being connected are twisted together just how. Those who are familiar with electrical engineering know that transition resistance occurs at the point of contact of two conductors. Its value depends on two factors:
- surface area at the point of contact;
- the presence of an oxide film on the conductors.
To perform twisting, the core is exposed, the metal interacts with oxygen in the air, as a result of which the surface of the conductor is covered with an oxide film, which has a decent resistivity value.
An example of poorly executed twisting: the twisting area heats up and the insulation melts
Accordingly, if the twisting is performed poorly, the contact resistance increases, which in turn will cause heating when an electric current passes through the joint. As a result, the twisted area may become so hot that the electrical wiring may catch fire. Surely everyone has heard the phrase in their life that a fire occurred due to a fault in the electrical network.
To prevent this from happening, the contact connection of the wires must be as strong, reliable and safe as possible. That is, the twisting must be performed so well that the contact resistance is stable and does not change over time.
Preparing wires for twisting
Remember! Never twist under voltage, even if you have a tool with insulated handles and dielectric gloves. First, de-energize your workplace by turning off the input circuit breaker for your apartment or house.
To get a good twist, you need to follow these steps exactly:
- Strip the connected conductors of insulation, while avoiding damage to the metal surfaces of the conductors.
- Soak a clean cloth in white spirit or acetone and wipe the exposed areas of the wires to remove any dirt.
- Now, using sandpaper, sand the wires to a metallic shine.
And then you can start twisting.
Stranded wires
Twisting of stranded electrical wires can be done in different ways.
Parallel twist
The simplest method is parallel twisting, when both stripped wires are placed crosswise on top of each other at the place where the insulation was stripped and twisted at the same time. Such a connection provides reliable contact, but it will poorly tolerate the applied tensile force and vibration.
This method is best used for copper wires, when one of them is monolithic and the other is stranded. A monolithic wire needs to be stripped of insulation a little more than a stranded wire. After twisting, an additional bend is made from the remaining copper monolithic tail in the direction of twisting, due to this the connection is more reliable. This method is also suitable for twisting aluminum conductors with different cross-sections.
Another advantage of parallel twisting is that it can be used to connect more than two wires at the same time.
Serial twisting
With the sequential method, each connected wire is wound onto another. The reliability and contact of such a connection will be optimal, but this twist can only be used for two wires, no more.
Place the stripped wires crosswise on top of each other approximately in the middle of the exposed area and begin to twist. One wire goes around another wire, and wrap the second wire around the first in the same way.
Bandage twist
Stranded wires can be connected together using the bandage twist method. In this case, the connected conductors are stripped to the same length and applied parallel to each other. In this position, they are fixed with a third wire, which is tightly wound onto the bare surface of the connected conductors.
Please note that using such twisting you can connect hard stranded wires, but you must use a soft (flexible) wire as a fixing wire. The more tightly you wind the fixing wire, the more reliable the contact connection will be.
More than two conductors can be connected using bandage twisting.
Solid wires
All of the methods discussed above for twisting multi-core wires can also be used for single-core wires. But it is best in this case to use a parallel connection.
Remember the most important thing: before connecting single-core wires, the insulating layer on them should be stripped only along the conductor at an angle. This is especially true for aluminum conductors. If you run a knife at a 90 degree angle around the conductor, the insulation will, of course, be removed. But in further work, with the slightest movements at the place of the cut, the conductor will eventually bend and, ultimately, the core will break.
Strip the insulating layer by 3-4 cm on the wires to be connected. Place the wires on top of each other at an angle of 45 degrees, but not in the area of the bare wires, but 1.5-2 cm above the place where the insulation was cut. Hold this place firmly with your left hand, and with your right hand begin to twist both wires. First, they will be twisted together with the insulating layer, then the connection of purely bare conductors will begin.
No matter how strong your hands are, be sure to finish twisting with pliers at the end, especially when it comes to aluminum wires.
Another important tip! After you make the twist, do not rush to insulate it. Let the electrical circuit work for several hours, then turn off the input circuit breaker for the apartment and check the temperature at the place where it is twisted. If the node is hot, it means that the contact connection is unreliable and it is better to redo it. If no heating is detected, then the twisting is done well and can insulate it.
If you need to perform a large number of twists, you can use a screwdriver with a homemade device, as shown in the video below:
Methods for insulating twists
Twisting the wires is half the battle; it is very important to properly insulate this place. There are three ways to insulate a completed electrical assembly: using insulating tape, heat-shrinkable tubing, and PPE caps. Let's look at each of them in more detail.
Insulating tape
Insulating tape is a special material whose main purpose is to insulate the junction of electrical cables and wires. No matter what modern technologies appear, you can hardly meet an electrician who does not have a roll of electrical tape in his pocket. This is the most common and inexpensive insulating material.
There are many varieties of it. Tapes are made from mica and fiberglass, polyester and epoxy films, acetate fabric and paper. To insulate twists in a household electrical network, we recommend using PVC tape (it is based on polyvinyl chloride). To make it, take a polyvinyl chloride film and apply glue on top. The quality of the insulating tape itself, and, accordingly, the reliability of the insulated joint depends on the quality of these two components.
The best is considered to be insulating tape, for the production of which rubber-based glue and class A PVC film are used. This material is distinguished by such positive qualities as:
- High adhesion (adhesion of dissimilar surfaces).
- Increased elasticity (excellent stretch and adhesiveness).
So be sure to keep this in mind when purchasing duct tape.
The insulating tape should be wrapped around the twisted section in at least two layers. Start winding 2-3 cm above the bare twist, the tape should be placed on top of the wire insulation. This will allow you to achieve maximum tightness and insulating reliability, and will protect the contact connection from moisture.
Next, wind it a little at an angle, moving towards the end of the twist. Having reached the end, bend the electrical tape around the tip of the twist and continue winding in the opposite direction. Having reached the place where you started winding, cut the insulating tape with a knife.
For efficiency, you can repeat the same thing again and make four layers of insulation.
It is recommended to use this tape to insulate strands installed in dry rooms.
Thermal tube
Heat-shrinkable tube (abbreviated as HERE) is made of thermopolymer materials that have the ability to change their geometric shape and dimensions (shrink or expand) under the influence of hot air, water or elevated temperature.
The main advantage of thermal tubes is that they can be attached to objects with a complex profile, which is exactly what twisted wires have. Heat-shrinkable tubing provides excellent electrical insulation and protects against mechanical damage. The tubes come in different diameters. The material from which they are made does not support combustion and is non-toxic.
Industrial hair dryers are used to apply heat to the tubes. This tool is not cheap and it is not economically profitable to buy it just to insulate the spliced wires. Therefore, at home, they often use an ordinary hairdryer or lighter.
It is important to remember that with this insulation method, the heat-shrinkable tube must be placed on one wire to be connected in advance (before twisting).
Cut the tube with a margin; when it is put on the bare area, it should extend onto the insulating layer of the conductor by at least 1 cm.
When the twisted connection of the electrical wires is completed, pull the tube over this place. Direct the heat jet of a hairdryer or the flame of a lighter at it; under the influence of hot air, the tube will instantly decrease in size and tightly seal the insulated area. Reliable, fast and inexpensive way.
Keep in mind that the connected wires, which are insulated with a heat pipe, can be used for laying in the ground or when immersed in water. This insulating material is recommended for use outdoors, in bathhouses and bathrooms, as it will reliably protect the twisting area from moisture.
How to use heat shrink tube is shown in this video: