Connecting electrical wires - 8 best ways

Today, there are many ways to connect wires in a junction box.

Using soldering and terminal blocks

These factors determine the choice of connector:

  1. Core material (copper or aluminum).
  2. Working conditions (on the street, in an apartment, in water, in the ground, in the floor, normal conditions).
  3. The number of conductors (two, three, four, etc.).
  4. Cross section (identical, different).
  5. Core structure (single-wire or multi-wire).

Based on these factors, the most suitable and correct method is selected. To begin, consider the materials with which you can connect the electrical wires in the junction box.

Existing methods

The following connection options are considered the most popular and effective:

  • use of terminal blocks;
  • installation of spring terminals (wago);
  • fixation with PPE (plastic caps);
  • crimping with sleeves;
  • soldering;
  • twist;
  • installation of "nuts";
  • the use of bolts.

Consider the nature, advantages and disadvantages of each of the methods!

Important! Immediately, we note that direct contact of aluminum with copper is not permissible, regardless of the type of connection. For this, adapter plates, washers, etc. are used. This issue is considered in more detail in the article:

Using terminal blocks

Terminal blocks They are plastic products, inside of which there is a brass sleeve, which has twisted screws on both sides.

Using terminal blocks

Terminal strip installation diagram

In order to connect two wires to each other using a terminal block, it is necessary to insert on each side at the end of the product and tighten them thoroughly with screws (with force). This connection method is most often used in junction boxes, as well as in installing chandelier, switches and sockets.

We draw your attention to the fact that terminal blocks come with a different inlet suitable for a particular section of the core.


  • low price of terminal blocks;
  • quick and convenient installation of products;
  • good quality bonding;
  • can connect aluminum with copper.


  • Very often, terminal blocks are of poor quality, which can lead to breakage of the connector during installation.
  • The ability to combine only two conductors with each other.
  • It is not recommended that terminal blocks be used to tighten aluminum and copper stranded conductors. This is due to the high fragility of aluminum and the thinness of the conductors of the stranded wire: when tightening the screws, the contacts can be damaged.
  • When using soldering, reliability will be much higher.
  • Flexible multi-wire cores for connection in screw terminal blocks of any design (including circuit breakers, sockets, etc.) are crimped with lugs of the type NSHVI and the like.

Spring terminals

Spring loaded wago terminals appeared on the market relatively recently and undoubtedly became the most effective and safe connectors.

Spring terminals wago (wagon)

Application of wago terminals

The difference between the wagon terminal blocks and conventional terminal blocks is that a special mechanism is used to connect the electrical wires, not a screw. This lever-type mechanism allows you to gently fix the product without damaging it. In order to independently fasten the wagons, it is necessary to strip the insulation and insert the cores into the hole.

We draw your attention to the fact that there are disposable and reusable terminal blocks wagon. The first option involves a one-time connection, and it will not be possible to restore it during the repair of electrical wiring: it will be necessary to cut off the wagon, repair the problem and install a new terminal block. Reusable wago terminals are more expensive, but they can be used to easily disconnect a contact if necessary. ”

Wago advantage:

  • depending on the terminal block model, the connection of copper and aluminum conductors is allowed, as well as the protection of aluminum from oxides using quartz-vaselin paste .;
  • the ability to connect several cores at the same time (more than two);
  • wago clamps allow you to fix a thin stranded wire without damage;
  • terminal blocks are very compact;
  • work does not take much time;
  • good quality bonding;
  • the car terminal block has a special hole that allows you to control the operation of the mains using an indicator screwdriver.

Only flaw - Higher cost of terminals, but this is not critical even for household wiring. It is also important to note that WAGOs are not suitable for connecting wires from powerful consumers, such as an oven or electric stove. These terminal blocks are more suitable for switching circuits in the outlet line, as well as lighting groups.

You can learn more information about using vag from our article:

Installing PPE caps

PPE stands for connecting insulating clamps. Products are ordinary plastic caps that have a special spring inside, which holds the wires.

Fixation lived in a box with gray

Most often, such caps are used to connect the cores in junction boxes.

Benefits of using these products:


  • relatively poor quality of insulation and fixation;
  • it is impossible to connect aluminum with copper.

About how to use PPE for connecting wires, read our article:

Crimping with special sleeves

Crimping with sleeves is one of the most reliable options. Its essence lies in the fact that the bare veins are placed in a special tube - a sleeve, and crimped with effort. After crimping, the sleeve is carefully insulated with a heat shrink tube (cambric) or electrical tape.

Pressure sleeve

Bonding Stages

Conductors can be routed from different sides of the tube or from one side. In the first embodiment, their joint should be approximately in the middle of the sleeve, in the second case, the cross-section of all cores (total) should not exceed the cross-section of the sleeve.


  • high-quality connection and isolation;
  • sleeves have a low cost.


  • The sleeve is disposable (one-piece). If repair is necessary, the sleeve must be cut off and discarded, after which a new one must be installed.
  • A special tool is needed for the connection: a press pliers and a pipe cutter (in order to shorten the sleeve if necessary). You can also use special stripping toolwhich has a compact crimp device.
  • It is possible to compress aluminum and copper wire only with a special sleeve, which is not often seen on sale.
  • Electrical work will require more time.

Soldering or welding

This method is the highest quality of all. In order to connect the two wires together in a junction box, it is necessary to carefully strip their ends, twist them and dip them into the molten solder. Further, the cores must be immersed in a soldering bath. After that, they should cool down and, in the end, be insulated with cambric or electrical tape.

Graphic diagram

Spike aluminum wiring photo

If you do not have a portable crucible for soldering wires, you can do it yourself as shown in the video:

Or solder with a soldering iron, but in this case a 3-4x spike lived with a cross section of 2.5 square meters. mm is difficult. Therefore, for soldering thick wires, it is necessary that the soldering iron has a thick copper tip with good heat capacity and a power of 40, and preferably 60 watts or more.

We draw your attention to the fact that it is strictly forbidden to cool the solder in cold water, as in this case, the quality of bonding will noticeably deteriorate (due to the appearance of microcracks).

Advantage soldering method - excellent connection quality and reliability.


  • the need for a special tool - a soldering iron and, accordingly, the ability to work with it;
  • the complexity of the work;
  • one-piece soldering;
  • restriction in conditions of use according to PUE;
  • soldering resistance increases over time, which affects voltage losses and electrical conductivity.

Based on this, soldering is recommended to be avoided using more modern bonding methods.

It should be noted that there is also a connection of electric wires by welding. The process is similar, but requires the use of a welding machine instead of a soldering iron, and, consequently, skills in welding.

These two methods of connecting wires in a junction box are discussed in detail in separate publications:



Twist and isolation

The old "grandfather" method consists in twisting the veins among themselves. The essence of the work lies in the fact that the conductors are stripped and carefully twisted with pliers, after which the place of twisting is isolated.

Options skutok

Core twisting


  • simplicity of electrical work;
  • lack of material costs.


  • poor quality of vein bonding;
  • connection of aluminum and copper products is unacceptable.

Most often twisting wires used in the installation of temporary wiring. For insulation, it is recommended to use cambric. According to the PUE, this method of connecting wires in a junction box cannot be used in rooms with high humidity and in a wooden house.

Nut Clamp

"Walnut" is a cable clamp that has two special plates and four screws in the corners, as can be seen in the photo below. For wire connections walnut it is necessary to strip the two ends of the wire and fix it in the plate, then put on the carbolite sheath.

Nut clamp

The use of


  • low cost of clamping;
  • the installation process of the "nut" does not cause any difficulties;
  • can connect copper and aluminum conductors;
  • good enough insulation.


  • it is necessary to periodically tighten all the screws;
  • the dimensions of the "nut" are not suitable for installation in a junction box or other compact places.

Bolt use

A simple, but nonetheless effective option for connecting electrical wires to each other is with a bolt. All you need is to have a short bolt, 3 washers and a nut on hand.

Circuit bolt connection

Bolted connection

A washer is put on the thread of the bolt, then a stripped core is wound, after which another washer - a core - washer is placed (as shown in the diagram above). In the end, the bolt is carefully tightened with a nut and insulated.


  • simplicity and minimum cash costs;
  • can connect aluminum and copper conductors.

As for the disadvantages, they are as follows:

  • low quality of fixation;
  • need to spend a lot of insulation;
  • the bolt dimensions will not fit in the junction box.

In more detail about how to connect the wires with a bolt, we described in the article:

We figured out the existing methods of connecting the wires in the box, now we will consider the remaining, important issues of this topic.

What to do if there are several wires?

When bonding two contacts, problems usually do not arise. But what to do if at the same time it is necessary to combine three, four or more?

Wago terminals

Wago terminals

In this case, it is recommended to opt for the following connection options (from best to worst):

  • using wago terminal blocks;
  • crimping with sleeves;
  • soldering;
  • twisting using sizy;
  • twisting and wrapping with electrical tape.

The order of connecting the wires for each of the methods we examined in detail above. We strongly recommend that you use the first option, as It is one of the most modern and efficient. At the same time, the cost of vag is not too high, and the wiring lasts more than 30 years.

What if veins of different sections?

To connect the wires of different sections in the junction box, it is recommended to use all the same terminal blocks of the car, or a cheaper option - ordinary terminal blocks. In this case, it is necessary to carefully tighten the cores with a screw or fix them with a flag, and that’s all, the work is finished.

WAGO application in electrical work

We draw your attention to the fact that if the wires are made of various materials, it is necessary to use special pads with paste inside, which will prevent oxidation of the wires. These pads include wago products.

Also, veins of different sections can be fixed by soldering.

Combining stranded and solid wires

The connection of single and multicore wires individually does not have any features, so you can use any of the above methods.

One option: using spring terminals

In order to carry out the bonding, you must choose one of two options: the terminals of the car or soldering. Here it all depends on your preference, the advantages and disadvantages of each method we have provided.

How to carry out work in water and land

During electrical work, a situation often occurs when it is necessary to fasten the wiring under water or in the ground. Now we will briefly consider the features of each of the cases!

In water (for example, when installing a submersible pump), it is recommended to use the following technology. To begin with, the ends are soldered, after which the soldering place is carefully insulated with hot-melt adhesive, over which it is worn shrink. If everything is done efficiently and honestly, the joint will be airtight and safe. Otherwise may happen short circuit and power failure.

To connect the electric wire in the ground (for example, after mechanical damage), it is recommended to use the method provided above (hot melt and heat shrink), but it is better to protect yourself and use the following method. Clamp the ends of the cable with the terminal block, install a sealed junction box, and then carefully fill the box with special silicone sealant. We draw your attention to the fact that the track underground must be additionally placed in a pipe or duct to ensure reliable rodent protection!

It is also recommended to combine the damaged ends of the wiring in the ground using a special cable sleeve, as in the photo below!

Clutch use

Using Heat Shrink Tubing

That's all I wanted to tell you about this issue! If any nuance has been missed, we advise you to watch visual video tutorials. We hope that now you know what kind of connectors are best used for certain application conditions, as well as how the wires can be connected in the junction box.

Also read:

Visual video instruction on the use of each method

Video: methods of connecting wires in a box

Video lesson on the use of crimping

Video instruction on the use of soldering

(45 votes)


  • Alexander

    Hello to the master academics! Your site is very happy. You tell honestly and openly. Thank you for the electric lessons. I will study and advise others. You have everything from theory and advice to diagrams and video (visual live examples). There are no better options. You could freely organize specific thematic courses to educate the population at a professional level, which is interested in electrics at the household level. I found you. Urgent sit down for your lessons.
    Of course, being elementary illiterate is very bad. But there is nothing tricky in electrics. This is a science for men, to be strong and courageous, but also knowing how to fix the outlet, plug in something. This is aerobatics. Something you can, with caution and the basics of electricians, do it yourself. I already called the "pros" to the apartment. You hear only "Money-money", who will ask more? They just can’t do it, because after 5 minutes you have to screw and screw yourself. And for some reason, volts are always confused with watts. Fortunately, I do not confuse the battery with the toilet. And as soon as you get a curved screwdriver, then take out the dead. This is already too much, even for me. How can you not love your profession if the "pros" do not have their own tools? I have more tools than the pros. So much so that they began to ask me for pliers ?! And I doubted them, and began to think, but maybe I myself can somehow wiggle, try? There’s nowhere to rush. Theory first. Then practice on the wires, on a mini circuit. It is clear that you can’t do without an electrician at the final stage if you connect to your grandmother, i.e. to the phase. Moreover, all the masters are taken to do only 100 square meters. m, which I do not have.
    Sincerely. I wish you all enlightening benefits. Will you, there will be nanotechnologies. Without basics, nowhere.

    To answer
    • Admin

      Hello! We are happy to help and teach everyone the basics of electrics at the level of a home master! It is very pleasant that our activity is evaluated as it deserves, so we will definitely continue in the same spirit! Stay with us and any difficulties associated with electricity will be within your power! Sincerely, my.electricianexp Site Team!

      To answer
  • Valera

    Thank. An excellent site is very helpful in household chores with wiring repairs. You explain everything simply and clearly it’s great that there is a video.

    To answer
  • Artemiy

    I read - yes everything is correct beautifully and correctly. Probably useful, but wow, not for me since I already knew all this 😉
    I don’t know why, but I don’t have confidence in the car - for some reason the device seems unreliable and flimsy. I prefer to solder everything. (I do it only for myself - I have another specialty)

    To answer
  • Igor

    Tell me what to do, there is no current in the switch, and in the chandelier itself, in the distribution box, I found one wire that is not twisted anywhere, what should I do? Aluminum wiring ... All in one color ...

    To answer
  • Oleg

    I ask for advice! At the top, a neighbor opened parquet and broke the wire of my overhead light. The wire is aluminum. They cut off the broken piece and inserted a copper cable connecting it with the clamps of the carriage 222. Subsequently, this whole thing will be filled with a screed forever. Are vaga cleats suitable for these purposes? Or advise some other connection.

    To answer
    • Admin

      I would not trust such a wago connection, nevertheless they are put in distribution boxes with the possibility of service. I would advise a sleeve connection.

      To answer
      • oleg

        And are the liners placed on copper-aluminum or aluminum-aluminum?

        To answer
        • Admin

          There are tinned sleeves, they can connect different metals.

          To answer
    • Dmitry

      Throw away aluminum, exchange for a copper wire while there is an opportunity. And you will be happy.
      Or as the administrator advises to compress through a special sleeve.

      To answer
  • oleg

    Thank you, the sleeves are more credible.

    To answer
  • Oleg

    Tell me, what kind of chatter is better to buy?

    To answer
    • Admin

      In order to compress a pair of shells it is not necessary to have pincers, a pliers hammer and a core are needed. Since the compression will take place on the floor, it should not cause any special difficulties. The principle of crimping is the same as with pliers, deformation of the sleeve and wire to full contact. The stripped wire should go up to half the sleeve, with the pliers we press the sleeve so that it does not come off the wire. Insert the second end and repeat. Having installed the prepared sleeve on the hammer, a punch in the center of the sleeve begins to deform it inward. The more dents the better. The entire length of the sleeve. Well, then you need to isolate it well.

      To answer
  • Dmitry

    Hello! Thanks for the site! A lot of useful information. A familiar electrician does the usual twisting and crimps with a simple screw terminal. Says that it is quite reliable. How right is he?

    To answer
  • Eugene

    Good afternoon!
    Please tell me which terminals of the car (if you can use them) are better to use to connect the 32-watt LED lamp on the street and is it necessary to additionally isolate the terminals or is it just enough to simply separate them apart? I'm worried about the effects of ultraviolet and about the rains ...

    To answer
    • Admin

      Well terminal blocks make sense to part? They are cooler than any electrical tape and protect against slight mechanical damage if water does not get in there, and if it rains, it is better to hide them under the cover or insulate on both sides with heat shrink.

      To answer
  • Admin

    For the street, Wago 222 is suitable.

    To answer
  • Alexei

    Good afternoon! Very useful site. You mentioned the presence of paste in the terminal blocks of the car. Is there a paste in everyone and is it visible to the naked eye?

    To answer
  • Taras

    Can you write a more comprehensive article about connections? I wondered - how to lay high-quality wiring, bit by bit I collected information about connection methods, terminals, their purpose and installation methods, with pluses and minuses. It would seem a banal question - how to qualitatively and permanently connect 16kv aluminum and 10kv copper wires for a long time, puzzled for half a week
    I could help with writing, but my knowledge is theoretical

    To answer
    • Admin

      Hello! We also wrote separately about each connection method. It is best to connect an aluminum and copper wire of such a cross section through a bolted connection. A chrome-plated electric washer must be placed between the conductors.

      To answer
  • dima

    Hello everyone. My question is, can I connect the wires in the room in such a way that when the switch is turned off, the cutters and the light switch do not work in this room? if not why

    To answer
  • dima

    and here in general give answers?

    To answer
    • Admin

      They give, but not so fast, many visitors, many questions. Everything is in order. About your question - it is possible, but it is necessary to draw a separate line from the apartment meter. And switch in the distribution box of the room.

      To answer
  • Alexei

    thanks, helpful! in this article I learned about Wago, and earlier I had to connect several wires with the help of terminal blocks, although write that this will not work, but it turns out. I will continue to use Wago

    To answer
  • Michael

    Good afternoon!
    Tell me please.
    The aluminum wires in the old outlet are brittle, they are too short. Gonna build up copper.
    The cross-sectional area of ​​the old wires and new copper is the same, 2.5 mm square.
    How reliable and safe is it to connect wires using WAGO 2273-242 with paste?

    To answer
  • Michael

    Yes, and also in continuation of the topic.

    The terminal strip indicates a stripping value of 11 mm.
    This means stripping:
    1) a maximum of 11 mm;
    2) at least 11 mm;
    3) strictly 11 mm?

    To answer
    • Admin

      In your case, VAGO terminal blocks will be a perfectly rational option. Once it is written 11 mm, it means strictly 11 mm and expose the core.

      To answer
  • Michael

    So it happened.
    The thick aluminum wire had to be cut more, not 11, but 13 mm, otherwise the insulation did not allow the wire to be inserted to the required depth.
    Waiting for criticism ..

    To answer
  • Sergei

    I usually do a tight twist and immediately carefully service it. It turns out twisting + soldering. There have never been complaints, although, of course, the complexity of such work is quite large, especially when it is necessary to solder three or more wires at a time. I look towards the WAGO connectors, but I'm afraid that with a serious current load, the spring clip in the connector will start to heat up and burn out. I did not see any information about the use of WAGO for wiring with a total power of consumers in the region of 10 kW. For the uninitiated: lighting, an iron, a microwave, an electric oven and some kind of kind heater, turned on at the same time will create about such a load. Therefore, while I do not apply WAGO, it’s enough that at the same time our carefree citizen will turn on 🙂

    To answer
  • Liana

    Good day!! Please tell or, if possible, show how to connect the wires. Theoretically understand :-), but I doubt it. Which nests of the wire do they enter and into which do they exit, so that there is no short circuit? How do you understand by designation? Thanks in advance to everyone 🙂

    To answer
    • Kerk

      Liana, the closure will still be. This type of terminal serves to connect the wires, in the case on your photo - four.

      To answer
  • Kerk

    It is necessary to supplement the article.
    Firstly, about Vago terminals, the so-called "Rigid" - designed for wires with monolithic conductors. Installation is simple: the stripped wire is simply inserted all the way. Dismantling - pull out the wire by scrolling through the terminal.

    Secondly, adhesive tape lock. One-time connection, reliable, safe, compact. There are models with a filler (gel) that allows their use, for example, with the subsequent termination of the connection point with mortars.

    To answer
  • Dmitry

    Good afternoon. I looked at the article, the impression was generally positive. 5 (fifth) photograph from the end of the article caused bewilderment. WAGO clamp 5 pin with a connection of wires, different cross-section. Explicitly power with twisted pair wires. IMHO this is unacceptable to anyone except the Chinese. I will explain by looking at this photo a non-knowledgeable person will conclude that 220 can be connected with a wire not intended for this purpose. (Think of a bell, LED bulb, etc. Low-power loads. But only in the case of a short circuit, these very thin wires are lit, and the machine will work (maybe) after a fire.)

    To answer
    • Admin

      Hello! In general, I agree with your perplexity, but the photo is taken as an example to show the terminal block, i.e. the topic of the article is different and does not apply to the problem of this very photo :)

      To answer
  • S

    Just now I was changing a car filled with KVP. I stood for six months at the customer.
    However, these are stable applications, once a couple of weeks to roll, replace like that.

    To answer
  • Ivan

    Also faced with WAGO burn-out in the distribution boxes, but mainly in houses with aluminum wiring and ASC on the stairwells. Therefore, I apply strictly pressure testing of GMF and subsequent insulation with two layers of heat shrink, preferably glue.

    To answer
  • Sergei

    What is the best way to make branches for outlets, if there are a lot of them? Using the terminals, you will have to cut the main cable in each box, which reduces the reliability of the wiring as a whole and increases its cost.If you make bends using the "old-fashioned" method - twisting a bandage type, then you can not cut the main cable and, moreover, use a cable with a larger cross section. The benefits seem to be obvious. What do you say about this?

    To answer

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