How to weld copper wires at home

How to weld copper wires at home?

The need to weld copper wires is associated with increasing the reliability of electrical networks. This is a durable, strong type of connection and is therefore in demand in various areas of production. The technology is accessible to beginners and requires the use of relatively simple equipment.

Copper wire welding technology

Connecting the wires can be done in two ways:

• contact, make a twist;
• perform welding.

Specific options are selected based on connection quality requirements, wiring operating characteristics, electrical characteristics, and the availability of suitable equipment.

Welding is performed on direct or alternating currents at voltages from 12 to 36 V. Equipment is used that allows precise adjustment of the current in order to select parameters for specific work conditions and workpiece parameters.

It is beneficial to use inverters that have sufficient power (up to 1.5 kW) and a current adjustment range in the range of 30–120 A.

As a conductor holder, special pliers or clamps are attached to the cables coming from the inverter. In this case, the pliers are connected to the ground of the device, and the clamps are connected to the positive output.

In addition to the fastening function, the pliers also serve as a heat sink. Therefore, overheating of copper, the appearance of cavities or other types of defects are excluded. The insulation of current-carrying conductors will also not be damaged when heated and will retain all its properties.

For spot welding, it is allowed to use transformers whose power does not exceed 500 W. The voltage is selected in the range from 12 to 36 V. The technology consists of short-term contact of the twist (1–2 s), fixed on the contact conductor, with a ground (holder) connected to a current source.

Features of welding copper wires

Welding copper wires has the following features:

• only graphite electrodes are used;
• the insulation stripping length must be more than 50 mm;
• the welding process should be short-term so as not to melt the core and not damage the insulating material;
• When working, it is important to use protective equipment against burns and electric shock;
• suitable modes are determined experimentally, so it is recommended to practice in advance on separate sections of the conductors.

Stripping copper wires for welding

Copper wire welding machines

Welding of copper conductors is carried out using devices with voltages up to 20 V. Inverter or transformer equipment is used, which allows igniting a small arc.

How to choose a device

The selection of machines for welding copper conductors is based on the following criteria:

• maximum welding current;
• power;
• dimensions, weight;
• availability of preset operating modes.

The following equipment can be used as a power source for electrodes:

• transformers;
• inverters.

Transformers

To weld copper wiring, it is sufficient to use adjustable current transformers (load of at least 400 A), since short-term heating to +10800C is required. Work must be performed when connected with straight polarity, since under such conditions stable arc burning is ensured.

Step-down transformers are used for welding any types of copper wiring, including work in a junction box. The welder may only be used to connect de-energized wiring.

Welding is carried out with a welding current selected in specific technical conditions. The ability to fine-tune electrical parameters is important.

Inverters

Welding wires with an inverter is advantageous, since it has compact dimensions, optimal preset parameters for current and voltage, and convenient adjustments. Unlike transformers, they are compact in size.

The technology for using an inverter is similar to using a transformer. When choosing, you should take into account the presence of current adjustments in the range of 40–200 A. It allows you to simplify the ignition of arcs, since the amount of interference and interference through the current source is minimal.

The inverter welding method is suitable for beginners, as it is quite simple to implement.

Is it possible to make a welding device from scrap materials?

Welding machines have a simple design. Therefore, it is not necessary to purchase ready-made assemblies, especially for one-time work.

Devices for welding copper wires are structurally composed of a transformer, control devices, regulators, a clamp, and ground.

A transformer must be used as a basis. You can take it ready-made or wind it yourself, provided you have the appropriate equipment and skills. The number of turns and wire cross-section are selected by calculation based on the input and output parameters.

Basic requirements for transformer characteristics:

• a step-down transformer;
• output voltage range from 12 to 48 V;
• current regulation within 40–150 A.

The welding device can be improved by adding an AC voltage welding function. To do this, you will need to install a diode bridge. With its help, the arc will become stable.

From the outside, the transformer should be protected by the housing from foreign objects getting inside, as well as from electric shock to the operator. Two wires should be connected to the transformer: for the holder and for connecting the ground. It is recommended to use special clamps as a holder, and massive pliers as a mass.

Electrodes for welding copper wires

The following electrodes can be used for welding copper conductors:

The carbon electrode has a number of the following features:

• the temperature at which melting occurs is +38000C;
• work is performed on direct current with straight polarity;
• relatively low arc efficiency;
• it is permissible to perform work with additives, without additives, with their supply directly to the seam formation line;
• the carbon electrode for welding at high temperatures of the structures being welded is consumed quickly;
• a high-temperature arc is created between the electrodes and the surface of the cables even at low current values.

The welding process with a graphite electrode has the following features:

• During the welding process, the electrode remains intact;
• copper's resistance to oxidative processes increases;
• It is permissible to use non-copper-plated electrodes; to do this, it is enough to twist the wires, clamp them with a holder and perform the standard welding procedure;
• the welded connection is reliable, but for this, the cores must be twisted tightly, and the excess ends must be properly cut to ensure a tight fit of the material.

How to weld copper wires

Step-by-step welding of wires with your own hands at home:

1. At least 10 cm of insulation is removed.
2. Twisting is done.
3. The ground is connected to the conductor from the transformer or inverter.
4. The inverter power is turned on.
5. The electrode is brought to the twist welding point to such a distance that a stable arc will be formed.
6. The arc is maintained for 1–2 s.
7. The electrode is retracted to another twist if multi-core wires are welded.
8. The inverter turns off.
9. Wait a certain amount of time for the wires to cool down.
10. The exposed twist contacts are insulated with heat-shrinkable tubing or electrical tape.

Welding copper to aluminum is difficult because it is impossible to precisely control the composition of the weld. With a copper content of more than 12%, the alloy becomes brittle and unreliable. Features of the welding process:

• Direct current is used, the connection polarity is straight;
• aluminum rods are used as an additive;
• The current is selected from 500 to 550 A, and the voltage is 50 to 60 V;
• graphite electrodes are used.

Security measures

When welding strands of copper wires, it is important to observe the following safety precautions:

• it is required to ground equipment under current;
• It is prohibited to use wires for electrodes without high-quality insulation;
• Operation of welding equipment is carried out in standard modes that do not contradict the stated requirements of the manufacturer.

Welding is performed only in a protective environment without direct contact with air.
Therefore, a low-power device operating on alternating or direct current is suitable. Welding twists with your own hands

Source: https://metalloy.ru/obrabotka/svarka/mednyh-provodov

We perform welding of strands of copper wires with our own hands

In order to connect two wires, several techniques are used. This can be twisting, soldering or welding of various wires. The last technique is one of the most successful and frequently used. It helps to achieve long service life of electrical wiring.

It is mainly made from a copper composition rather than aluminum, which is not suitable for these purposes. Welding occurs using direct and alternating current, at a voltage of 12-36 V. Directly for the process, we recommend using an inverter welding machine.

Step by step process

Let's describe the whole process step by step:

1. Remove the insulation on the wires;
2. We make twists;
3. Add mass;
4. Turn on the welding inverter;
5. We bring the electrode to the twist until an arc forms;
6. Contact duration is 1-2 seconds;
7. We proceed to the next twist (if there is one), after the finished one has cooled;
8. We insulate using heat-shrinkable tubing or electrical tape.

Important! Welding wires with your own hands, especially copper wires, requires special experience and knowledge. You will have to work at a temperature of 1080°C, at which copper melts. Therefore, it is worth practicing with simpler examples.

The device should be selected with the ability to adjust the current, the strength of which should be 30-90 amperes. The electrode used is carbon containing copper.

Features of welding aluminum wire

Welding of aluminum wires, mainly found in large industries. For the welding process, use argon or a conventional welding machine. To avoid burning the wire, welding is performed at reduced power.

Some difficulties may arise in the form of an oxide film; the rate of its formation is very high. As a result, it remains on the molten metal. To avoid this, a gas shielding medium and aluminum cable flux are used.

Welding aluminum wire step by step

Let's look at welding aluminum wire step by step:

1. First, remove the insulation and all excess materials;
2. Next, the ends of the workpieces are treated with flux. This will improve the final quality;
3. Turn on the device and set the correct operating mode;
4. We start welding;
5. Then the excess parts that appear as a result of the work are removed;
6. We re-insulate the wire.

To ensure a successful welding, we strongly recommend that you adhere to safety precautions. You need to have fire-resistant clothing, a welding mask and special gloves with you. If gas is used, the cylinders are removed 5 meters or more from the fire. Check all equipment and assess indoor humidity to avoid electric shock.

Welding in a junction box

First, you should get acquainted with the box and appreciate its full significance. This is the most important part of all electrical wiring running throughout an apartment or house. Take this very seriously.

Directly for the soldering process you will need a welding machine. We can recommend one of the most attractive models for such purposes. This is the Patriot Max Welder DC-200 C. It has a silent level of operation, high safety, which is important if there is a lack of experience, and precise operation.

Its weight is 4.5 kg, so there are no problems with transportation. It is powered by a 220 V network, the current floats in the range of 10-190 A. The price is at an acceptable level for everyone, from 8,000 to 10,000 rubles.

This does not mean that you only need to choose this one; there are other devices that are just as suitable for this type of welding.

Welding of copper wires in the junction box begins with ensuring all safety measures. We set the device to a power of about 1 kW. Carbon and graphite electrodes are used. You will also need flux. A mask or special glasses must be used.

To remove insulation and twists of copper wires, you need a knife and a clamp in the form of pliers. Always have electrical tape, nuts and screws on hand. The wire strands are stripped to about 4-5 cm, then twisted around each other 7 times. Let's start welding.

If you are not confident in your abilities, practice on similar types of metal and twists. When everything works out, start. We have already talked about the procedure for welding copper wires earlier.

Thermite welding

Thermite welding of wires is perhaps the most popular method for connecting two current conductors. For the process itself, a special thermite mixture is used. To obtain the correct result, you need to adhere to all rules and recommendations to the nearest millimeter.

This technology is just beginning to gain popularity. It is increasingly used in a variety of areas of production. To carry out high-quality work, the welder must have special knowledge of chemistry at a high level.

Welding wire selection

This cable serves to supply current to the place where the parts are connected. Since the process is the most important, welding wires have high requirements, we list the main ones:

1. The insulation must be heavy-duty and withstand many twisting procedures;
2. The cross-section of the wire must be resistant to the loads created by the inverter;
3. Current-carrying conductors must be in a polymer braid;
4. The wire insulation base must be made of hose rubber;
5. The wire must be resistant to mechanical damage and also not weak to chemicals and aggressive environments.

What are wires for hardware welding made of?

• base winding made of polyethylene terephthalate;
• current-conducting conductor made of copper;
• rubber insulation;
• additional layer of winding;
• main insulation made of rubber.

When talking about lengthening the wire, you can sometimes hear that the quality of the seam may deteriorate. But direct evidence of such a feature has not yet been identified.

Source: https://electrod.biz/varim/svarka-skrutok-mednyih-provodov.html

Welding copper wires

Most electricians know that if wires are simply twisted together, this section will serve as additional resistance due to the difference in contact density between the solid wire and the twist. This area often overheats or burns. Mechanical circuit breaks are also possible. To avoid these problems, copper wire welding was invented. What is its technology? What devices are used to perform this? Is it possible to make such a device yourself?

Electrical wiring welding technology

The welding process for copper wires consists of igniting a short-term electric arc, melting the edges of the rods and connecting them into a single monolithic section, 3-5 mm long. This happens in the following sequence:

1. The wiring intended for connection is cleared of insulation to a length of 60-70 mm. This is done to prevent the insulation from melting from the heated copper.
2. I put the copper fibers together and twist them together. The type of twisting is not important, and it can be done either by twisting all the wires evenly, or by twisting some around the axis of others. It is the welding that creates the mechanical strength here, and not the type of twisting.
3. Twisted copper conductors must have a total length of 50 mm. The remaining branched part is trimmed to a tightly twisted bundle.
4. 25 - 30 mm from the edge of the connection it must be clamped with a clamping device, which is also the contact mass (negative cable from the device). The electrician will hold the wires to be welded using this element. Stripping that is too long and gripping far from the edge should not be done due to excessive overheating of the entire area between the contacts.
5. The second hand brings up a holder with a special electrode.
6. The end of the electrode comes into contact with the end of the twist and an arc is ignited, which must be held for 1-2 seconds (depending on the current strength and cross-section of the wire).
7. The edges of the wires melt from the temperature of the arc, forming a solid connection, the cross-section of which does not interfere with the passage of current.
8. By interrupting the arc, we finish the welding process and let the product cool.
9. The twist that has cooled after welding must be rolled up (for compact placement in the box) and covered with heat-shrink tubing or insulating tape.

To weld wires successfully, you need to practice on “rough” pieces of cable. A common mistake made by novice electricians is sticking the electrode to the end of the wire being welded.

This happens due to the distance being too short and the work being done overhead. To give clarity to the actions being performed, it is recommended to rest your hand with the mass against the wall, and press the hand with the electrode against your body with your elbow.

This can minimize wobble and vibration, which can cause welding problems.

You can tell that the connection is ready by the characteristic red bead of hot metal that has a solid appearance. The rounded shape will be the final proof that the rods have fused together.

Although the arc burns for only a few seconds, if extensive work is required (distributing the box, arranging the shield), it is recommended to wear safety glasses or even a chameleon poppy.

The ultraviolet radiation emitted by the arc can cause serious burns to the skin of the face and the cornea of ​​the eyes during prolonged welding.

The advantage of this method over similar work with a soldering iron is:

• no need for filler material (tin);
• no need to pre-tin the metal;
• welding of twists is carried out faster in time than soldering, which is more effective for large volumes of work;
• to solder wires of different diameters, you need soldering irons of different power, but the welding machine can be switched to suit any cross-section;
• some cables are so thick that they can only be joined by welding.

How to make a wire welding machine yourself?

If you have to do one-time, but extensive work with wires, then buying a store-bought device may not be profitable.

How to make a welding unit for these purposes with your own hands? For the base you will need a step-down transformer, which you can wind yourself or remove from old equipment.

The main criterion is the ability to reduce the input voltage to 12-48 V, while delivering a current from 40 to 150 A. You can calculate the number of turns and the required wire cross-section using the corresponding tables.

Although welding wiring can be performed using alternating current, it is better to install a diode bridge in your homemade apparatus to rectify the voltage. This will give the electric arc a characteristic rustling sound and it will be more stable. The completed unit must be equipped with a protective housing to prevent electric shock.

A holder for a carbon electrode can be bought in a store, or you can make it from a clamp for a trolleybus contactor or other clamping device. The second clamp for fixing the wire and connecting the ground is made of pliers. In one of the handles it is necessary to drill a hole for a bolt and a terminal for contact.

Parameters for welding wires

In order for the connection of wires to be welded efficiently, in addition to the appropriate equipment and skills, you will need to select the correct welding modes. The main ones are presented in the table:

Wire cross-section, mm square	Number of connected rods, pcs	Current strength, A
1.5	2	70
1.5	3	80
2.5	2	100
2.5	4	120

Connecting the twists by welding allows for reliable contact, eliminating overheating and mechanical breakage of the wires. How to do this in practice is shown in the additional video. And by creating your own device, you can save on equipment without sacrificing quality.

Source: https://svarkalegko.com/tehonology/kak-svarit-mednye-provoda.html

Welding copper wires with your own hands. Review of machines for welding copper wires

Is wire welding important?
Twisting is a very common type of connection for copper wires and is quite reliable. Welding greatly improves the quality of twisting, increasing its reliability and durability.

Reviews from professional electricians and tests from electrical laboratories indicate that twist welding is a guaranteed excellent wire contact that is not subject to oxidation and does not require revisions of junction boxes with tightening of contacts.

In modern electrical installations using expensive wiring components, this is very important. After all, electrics is also the science of contacts. First, let’s look at the options for electric devices for welding twists.

Types of welding machines

There are three main groups of welding machines used by electricians (and not only) to connect wires in modern electrical installations: • narrow-profile welding machines for welding strands of copper wires, such as the TS-700 and its analogues of Russian and foreign production; • general inverter welding machines appointments;

• welding machines of our own production from step-down transformers.

Description of these types of welding machines, their features

Welding machines for soldering copper electrical wires.
Factory-made welding machines for electric welding of copper strands are suitable only for electrical installation of wires. They are very easy to work with twists.

The device body is compact, with a carrying strap. On/off key, power wire, ground wire with clamp or retainer and electrode holder wire. They use special carbon electrodes for welding copper wires.

These machines can weld both rigid and stranded copper wires.

These are ordinary inverter welding machines, but they can also weld copper strands. Such devices are also easy to carry. It is better to use some kind of clamp to connect the ground wire of the device with twist. Also, experimentally it is necessary to select the optimal value of the welding current (from 60 to 110 A). Copper-carbon electrodes are used. Welding current is better constant.

Homemade wire welding machines

These are devices made by skilled electricians from various types of step-down transformers. In general terms, these are transformers with a power from 300 W to 800 W, with a voltage on the secondary winding from 9 V to 36 V. The ground wires and the holder are made of several wires, so that there is from 15 kW. mm. The electrodes in this case are often the carbon rods of the batteries.

How are twisted wires welded?

1. It is necessary to remove 50-60 mm of insulation from the wires and twist them.2. Use pliers or clamps to connect the twist to the ground.3. Electrode for 1 sec. scald the end of the twist to a ball at the end.

4. Cool and insulate the twist.

Who can weld copper wire strands?
Theoretically, anyone, as long as there was an understanding of electricity and electrical installation. Still, it is better to have a professional electrician do the welding of twisted copper wires. You need to pay attention not to burn the insulation of the wires, so that the twist is not short, but a drop of welding, if possible, without holes.

The most important and responsible component of the installation and assembly of power supply systems is. High-quality and reliable contacts at the points of connection of electrical network elements, made in accordance with the requirements of the Electrical Installation Rules (PUE), are a guarantee of operability, durability, and most importantly, electrical and fire safety. In this article we will tell you how to weld wires in a junction box with your own hands.

It is important to know

The simplest and fastest way to solve the issue of how to connect wires is considered to be, but at the same time, twisted wires represent a very low degree of contact reliability. Terminal blocks and crimping devices increase the reliability of installation, but are several orders of magnitude inferior to such a connection method as welding. When preparing for electrical installation, weighing all the pros and cons, you should definitely cast aside doubts and give preference to this method.

People who are not knowledgeable about electrical installation issues have the opinion that this connection method is an unacceptably advanced technological process that requires the highest qualifications of the performer and the use of highly complex equipment. In fact, everything is very simple and accessible. Welding wires with your own hands is entirely within the capabilities of a person who has basic skills in handling an electric welding machine at home.

The question is very relevant for our time, since inverter welding machines became available for mass purchase. The inverter welder is very convenient and practical, with a low current load consumption and reasonable cost, for which it has earned popularity among home craftsmen.

As a device, you can use a homemade device made on the basis of a step-down transformer. For a person who has knowledge and skills in the field of electrical engineering, the question is not difficult.

Electrical installation companies specializing in welding use special welding machines in their work.

What do you need to prepare?

In addition to the apparatus for welding work, you should prepare and have available all the necessary equipment, materials and tools. The wires are welded using carbon electrodes. For the manufacture of conductor products, copper and much less often aluminum are used.

For information, according to the latest PUE requirements, the use of aluminum conductors with a cross-section of less than 16 mm 2 is prohibited. Depending on what will have to be welded - aluminum or copper, the composition of the flux is selected, designed to chemically dissolve the oxide film formed during welding.

In the process of preparing the ends of the conductors and as work progresses, you will need a knife, pliers, and electrical insulating materials.

By the way, an alternative option is . Read our article about how to properly solder wires!

Process Features

Before you start welding electrical wires, you should set up the machine. Considering that the conductors being welded can be of different cross-sections, the current at the anode of the welding machine must be selected in such a way as not to cause overheating of the connected conductors or sticking of the electrode at the connection point. The ends of the conductors must be stripped of insulation (bare conductors must be 5 mm long) and connected to each other, as is done when twisting.

Having pre-treated the twisted bare ends with flux, we clamp them with pliers and attach the mass to them, the electrode is brought to the end of the twist, which should be directed downwards, and held in this position for 0.5 to 2 seconds.

Once you are sure that a copper or aluminum ball has formed at the point of contact, stop welding. After the connection has cooled, remove the flux with sandpaper.

Before applying an insulating coating to welded wires, it is recommended to treat this area with a solvent, followed by coating with electrical insulating varnish.

It is strictly forbidden to connect live conductors. Before starting work, using a probe, you need to make sure that it is missing. To protect your eyes, face and hands from burns when working, be sure to use a protective mask and gloves.

The technology for welding copper wires with an inverter is shown in the video:

For aluminum wires, there is an alternative welding option - using a gas torch. In this case, it is necessary to prepare the current-carrying conductors in the same way as for electric welding, with the exception of flux treatment. To work, you will need a steel rod with a cross-section of about 2 mm. The joint must be heated with a gas burner until signs of melting appear at the welding point at the end of the twist.

When melting, liquid aluminum is enveloped in a kind of cocoon consisting of an oxide film that interferes with the joining process. After making sure that the aluminum has melted, to complete it, it is necessary to destroy the resulting layer of oxide film simultaneously with heating using a steel rod, which will ensure a reliable welding process.

Like(0)Dislike(0)

The main element for welding wires is a welding machine. You can buy it ready-made in a store or make it yourself. Let's consider both options.

Inverter

Factory-made electronic welding machine. Its direct purpose is metal welding. It can be used for welding wires without modification. To do this, graphite electrodes must be used as an electrode.

There are a large number of inverters on the market at an affordable price, small in size and weighing about 3 kg, which is very important for electricians, since they often have to weld wires under the ceiling while on a high ladder.

Source: https://linkor-best.ru/welding-copper-wires-with-your-own-hands-survey-of-devices-for-welding-copper-wires/

How to weld copper wires at home

Copper wires are more practical than aluminum wires; they are often used for wiring in private homes and laid when renovating apartments. Several ways of designing cable joints are allowed: they are secured with terminals or soldering.

Crimping or compression of the twist is allowed, but the most reliable connection is formed by molten copper. To weld copper wires on a line or in a distribution box, spot technology is used.

It is necessary to melt the twist to a homogeneous structure so that the resistance in the circuit does not increase. This is done for fire safety.

Soldering or welding copper wires - which is better?

The simplest and most effective soldering method is to immerse the contact point in molten solder. For small circuits this method is suitable. But it is not suitable for installing lines made of copper wires. Soldering with tin solders by weight requires skill; beginners cannot cope with such work, and there is a high risk of injury. Connecting wires with your own hands using contact welding is much safer.

Another advantage of welding is that the chemical composition of the wires does not change, and no solder particles get into the alloy. The electrical conductivity of the copper cable at the point of twisting does not change. Welding is faster than soldering; there is no need to pre-tin the contacts or select a soldering iron according to the power of the cable size. There are multi-core cords that cannot be soldered.

Welding has the only drawback: if you do not have the skills, you can damage the integrity of the insulation of the copper wire.

Welding machine

For welding copper wires, any current generator is used: transformer, rectifier, inverter. Resistance welding pliers are connected to car batteries, the two are connected in series, and the contacts are brought out to the electrodes. There is enough power to connect the cable to a 5 mm core. You can’t do a large volume with batteries; you need a welding machine.

Source: https://svarkaprosto.ru/tehnologii/svarka-mednykh-provodov

How to Weld Copper Wires - Technician Expert

The most important and responsible component of the installation and assembly of power supply systems is the connection of wires in distribution boxes.

High-quality and reliable contacts at the points of connection of electrical network elements, made in accordance with the requirements of the Electrical Installation Rules (PUE), are a guarantee of operability, durability, and most importantly, electrical and fire safety. In this article we will tell you how to weld wires in a junction box with your own hands.

What you need to prepare

In addition to the apparatus for welding work, you should prepare and have available all the necessary equipment, materials and tools. The wires are welded using carbon (graphite) electrodes.

As such electrodes, you can use either an industrial version (such as the EG brand) or a brush from an electric motor, a piece of a shoe from a trolleybus, graphite cores from batteries type 3336 (3R12) or modern salt ones. For the manufacture of conductor products, copper and much less often aluminum are used.

For information, according to the latest PUE requirements, the use of aluminum conductors with a cross-section of less than 16 mm2 is prohibited.

Depending on what will have to be welded - aluminum or copper, the composition of the flux is selected, designed to chemically dissolve the oxide film formed during welding. When welding aluminum wires, you need to use flux, copper can be welded without it, you must first clean the conductors in both cases

In the process of preparing the ends of the conductors and as work progresses, you will need a knife, pliers, and electrical insulating materials.

By the way, an alternative option is to connect the wires by soldering. Read our article about how to properly solder wires!

Do-it-yourself welding of copper and aluminum wires

The provisions of the PUE recommend welding of wires as one of the most reliable methods of connecting them. The advantages of using this method significantly outweigh the few disadvantages, which makes it popular among home craftsmen and professional electricians.

Pros and cons of welding, its varieties

The advantages of connecting wires by welding are the absence of transition resistance, which is always present in twisted or bolted connections. This is especially true when laying wiring for powerful devices.

The disadvantages are the need to buy or make your own welding machine designed for twisting.

Welding work requires some skills, so the electrician who will weld the strands needs to learn at least the basics of this craft.

When performing electrical installation work in production, various types of welding are used: standard, arc spot, plasma, torsion, electron beam, ultrasonic, or various combinations thereof. For domestic use, electricians most often use a device for spot and arc welding, which operates on carbon or graphite electrodes.

This solution allows you to obtain good quality connections at a minimum cost of the necessary devices and components.

When making a wire welding machine, most attention should be paid to the following characteristics of the device:

• The current strength that the device can produce. Ideally this is a variable value.
• The voltage produced by the device is sufficient to cause an electric arc - usually 12-32 Volts.
• What kind of current does the welder use - alternating or direct? If you have experience in such work, you can use variable, but for beginners it is strongly recommended to start with constant.

Since welding different metals requires different currents and voltages, universal welding machines can necessarily adjust these values.

In addition, when joining different materials, you may need special fluxes that will protect the metal from oxidation or the penetration of gases from the air into it.

Most universal-purpose welding machines are quite bulky and heavy, but for small welding jobs you can find inverter welders for a relatively low price that are ideal for welding wires.

If you are welding copper wires that are used in home wiring, there is no need to use very high current and voltage, so it is possible to use small-sized welding machines that fit into a standard tool case.

The principle of operation of arc welding - device diagram

Since welding requires a large current, the basis of any welding machine is a step-down transformer - a loss in voltage is always accompanied by a gain in current and vice versa.

A standard diode bridge is used to convert alternating current into direct current, and a capacitor is used to smooth out ripples.

A noticeable disadvantage of using a direct current device is that the diodes and capacitor used are rather large and they significantly increase the weight of the welding machine, which is initially made portable.

Experts also recommend installing additional resistance at the input or output of the diode bridge, since diodes “do not like” a short circuit in its pure form.

Many craftsmen manually assemble a welding machine for welding copper wires, which produces an arc from alternating current and use them successfully. Therefore, it is impossible to say unequivocally that it is necessary to use a direct current device - everyone chooses the necessary model according to their skills. If an AC welding machine is manually assembled, then the diode bridge and capacitor are simply thrown out of the circuit.

A necessary skill that you will have to master to use an AC welding machine is to learn “by eye” to determine how long you should hold the ignited arc of the electric discharge so that the end of the twist heats up and fusions.

The most common way to make a negative contact for welding is with old pliers that hold the wires.

For the phase, take a clamp that can hold the graphite rod. The design of the clamp can be very diverse - from a screw connection to the so-called “crocodiles”, both home-made and factory-made. To connect to the welding machine itself, cables with a cross-section of about 10 mm² are used.

Despite the fact that a device assembled in an industrial environment is an order of magnitude more expensive than a homemade one, its price is not exorbitant and allows you to purchase such a welding machine even on a limited budget. The advantages of its use are obvious - it is a precisely calculated design with a current regulator, which allows you to work with different types of metals and the number of wires being welded.

Nuances of the wire welding process

With the necessary skills, welding conductors does not take much time, but in order to obtain a high-quality connection, it is strongly recommended that you first practice on separate pieces of cables. Moreover, this must be done if you are using a twist welding machine that works with alternating current - you need to get used to the power of such a device. The whole process is clearly shown in the following video:

Step by step everything looks like this:

• Stripping wires. A feature of welding is the need to expose the wire cores to a length of 60-80 mm. Less is impossible, since during welding the wire heats up quite strongly and the insulation will melt.
• Twisting wires. It would seem that you can simply fold the wires and weld - a drop will still form at the end, which will connect everything together. The problem with this connection method may be the fragility of the wires - it is not a fact that it will occur, but for some reasons, the droplet resulting from welding with a carbon electrode acquires a spongy structure and is susceptible to fracture. This does not affect conductivity, but if the wires are not twisted, they may break.

• Trimming the twist. The fluffy ends of the veins must be trimmed to get an even cut. Then the arc during welding will evenly heat the entire surface of the twist and the drop will be even.

• Welding. The twist is grabbed with pliers and a graphite electrode is brought to its tip until an electric arc occurs. It must be maintained until the ends of the wires fuse, forming a smooth drop. The next twist is welded after the previous one has cooled.

If the arc does not appear, then the power of the transformer is insufficient or the wires to the electrode holders are too long (their resistance prevents sufficient current from being obtained).

The optimal option for the length of the wires is 2.5-3.5 meters, but in the first case you will have to place the welding machine on a stand for ease of operation.

• Twist insulation. The best option in terms of speed here would be to use heat-shrinkable casings, but to warm them up you will additionally need a hair dryer or a good lighter. There is also no hindrance to using ordinary electrical tape - except that it will take a little longer.
• Welding copper and aluminum wires. In general, it is performed in exactly the same way as a regular one - the only difference is in the preparation of the wires. The copper core remains straight, and the aluminum core is wrapped around it. Then flux is applied to the aluminum, which, when heated, removes the oxide film from this metal, and welding can begin.

But if you follow the instructions of the PUE, then in domestic conditions you are unlikely to have to work with aluminum wires, since the use of such cables with a cross-section of less than 16 mm² is prohibited for laying electrical wiring.

Welding wires with an inverter

The use of such a device is most preferable, since welding copper and aluminum wires with an inverter is much easier than with homemade welding machines. This is a universal device, the current in which is adjustable in the range of up to 160 Amperes. In addition to the fact that it can weld twists, it allows you to work with metal up to 5 mm thick - for home use this power is usually more than enough.

Typically, such a device is the prerogative of professionals who are constantly faced with welding work, but at the same time it can be safely recommended to beginners who are just mastering welding strands with their own hands. The “hot start” function, protection against electrode sticking and the ability to work even during voltage surges will allow a novice welder to quickly master the basics of this craft, and a professional will always enjoy working with a good tool.

If the device allows you to regulate the voltage and current, then “by eye” what values ​​to set can be determined by the diameter of the wires and their number.

Briefly about the main thing

Welding the ends of twisted wires significantly improves the conductivity of these contacts, and therefore the characteristics of the network as a whole.

Welding machines that allow spot welding are commercially available and are also simple enough in design to make them yourself. But in the second case, simpler devices that produce alternating current are most often assembled - such devices require certain operating skills.

In practice, there is not much difference in using one device or another - if the master is experienced enough, the result will be good in any case.

Source: https://YaElectrik.ru/elektroprovodka/svarka-provodov

How to weld copper wires?

Reducing the number of contacts in the electrical network makes it more reliable. One way to prevent contact between two electrical conductors is to weld them together. However, the installation of electrical circuits in most cases involves the use of mechanical connections based on compression.

Everywhere, electrical fittings are connected to wire cores using terminals with screws and nuts, as well as other mechanical systems (mostly connectors). But the wire strands of electrical wiring are available for welding. Next, we will tell you in more detail about how to weld wire cores when installing electrical wiring.   

Advantages and disadvantages in comparison with analogues

The simplest way to connect wires of the same metal is twisting. But along with simplicity, as it should be in life, there is also a drawback - a relatively large resistance at the twisting point. The cross-sectional shape of the core is a circle. Moreover, regardless of the diameter of the core. Two circles touch at a point, and two twisted wires touch along a narrow strip a fraction of a millimeter wide.

• The twist depends on the mechanical properties of the cores in connection with the ambient temperature. Without additional devices (for example, caps), the contact continuously degrades.  

Regular twist

Copper can be soldered well with tin solders. Therefore, soldering is an effective way to increase the contact surface of the cores and reduce resistance. But at the same time you need:

• high-quality surface cleaning,
• use of flux and solder,
• preventing oil from getting into the soldering area,
• optimal temperature conditions for the process.

It is best to immerse the prepared twist in a container with molten solder. But if it is located high, moving such a container is a dangerous task. In addition, the solder must also be heated. And this will require equipment and time. In addition, the adhesion of solder to the surface of the core is an uncontrolled process. If the temperature is not high enough, the solder will not provide the required soldering quality.   

Twist soldering Result of soldering at low temperature

To weld cores, only two components are needed:

• Practical skills;
• power source corresponding to the thickness of the cores being welded.

The advantages of welding are obvious:

• the core material is melted and mixed to form a single whole. The contact disappears as the two pieces of wire come together.

Welded copper conductors

There is essentially only one drawback:

• with insufficient experience, the insulation may melt and (or) a molten drop of copper will break away from the twist and fly down. You'll have to weld it again.

To obtain an optimal result when welding, the following sequence of actions is recommended.

1. Wires are being prepared. The vein of each of them is freed from insulation. It is recommended to remove at least seven centimeters for a core with a diameter of 1.5 mm. If the wires are thicker, for every 0.5 mm of core diameter, take 5 mm of insulation length. This is done to ensure that the insulation at the base of the twist is not destroyed by welding. The thicker the core, the faster heat spreads through it and the longer it should be.
2. The veins are twisted so that with a length of 7 cm they are shortened to approximately 5 cm. Their tips are then bent so that at a distance of 5–10 mm the veins are parallel and touching. The length of these ends should be the same. If necessary, you need to trim them with nippers.
3. Now you can start welding these ends together. For this you need an electrode. You can choose one of two options:

• a piece of the same twist;
• a graphite rod, for example, taken from a AA or larger battery, an electric motor brush.

Electrode made from an electric motor brush

1. Then you can proceed directly to welding. To successfully complete this process, you must light the arc and extinguish it in a timely manner. For this purpose, the wires of the welding fixture are made convenient, that is, one wire fits securely to the twist approximately in its middle part, and the other is connected to the welding electrode that is selected.
2. To obtain contact on twisting, it is recommended:

• make a petal out of a copper plate;
• bend it in half along the twist;
• solder or securely attach with a screw and nut to the wire of the welding fixture;
• apply a little conductive paste to the contact point between the twist and the petal;
• squeeze this place with pliers and hold it with your hand.

Welding copper wires

1. With the other hand, holding the other pliers, hold the electrode with the second wire of the welding device.
2. By connecting the electrode to the tip of the twist, we get an arc. It heats both the twist and the electrode red-hot. This emits a blinding light. To protect your eyes and to be able to see the condition of the welding site, you need dark glasses. Such that the place of welding is barely visible in them before the arc appears.
3. When it burns, it will be noticeable how the tip of the twist changes and rounds. This happens in a couple of seconds if the power of the welding device is optimal. Then the welding electrode is moved away and the arc goes out by itself.  

Rounded molten twist tip

Precautionary measures

Welding of copper wires is usually done in a new building, as well as during major or other renovations of the premises. Under these conditions, it is difficult to obtain reliable grounding of the welding transformer for high work safety. In many cases there is simply nowhere to get it. Therefore, it is necessary to use personal protective equipment that is guaranteed to isolate the operator from electric shock. Plus, you should take into account the possibility of splashing hot metal near the welding site.

Subject to technology and safety measures, welding copper wires will ensure the highest quality electrical wiring. Therefore, this method of connecting current-carrying conductors is recommended for the widest use.

The entire process of welding copper wires in one drawing

Source: https://domelectrik.ru/provodka/kabel/svarka-mednyh-provodov

Do-it-yourself welding of copper wires with a graphite electrode

Wires can be connected using different methods. Their differences lie in the dynamics of operation, the quality of contacts and the ability to operate continuously under heavy network loads. And the most reliable method is twisting and welding. But it requires a special device. Do-it-yourself transformer for welding copper wires

Requirements for a transformer for welding

This should be an AC device with an approximate parameter of 400 -600 W. The output winding must have a voltage from 9 to 36 V.

Carbon or graphite electrodes are used to connect copper wires or strands.

A copper heat sink clamp with a large area must be used. And the more solid it is, the better.

The unit must also be equipped with a current control option. The welding itself lasts a few seconds. To achieve the best effect, the cross-section and number of cores in the wire should be taken into account.

The following shows the relationship between these indicators and the required current power.

Section (mm)	Number of copper wires	Current(A)
1,5	2	70
1,5	3	80
2,5	2	100
2,5	4	120

Varieties

Inverter devices are the most popular. They are easy to purchase in the store. They have solid functionality and a range of capabilities.

The work is greatly facilitated by the “hot start” option. It protects the device from sticking and power surges. Thanks to a current of up to 160 A, you can weld metal with a density of up to 5 mm. This is enough for everyday tasks.

Good demand has been noted for such models as:

• Resanta SAI-160.
• QUATTRO ELEMENTI A
• PFTRIOTMax Welder DC-200 C

Transformers created by their own efforts can perform different types of welding:

• Dugovaya. Such a device is most often created by hand. It is characterized by a simple design, which, in addition to the transformer, consists of: a current controller, an electrode clamp, and a ground clamp.

In home-made units, a transformer is usually installed that has a toroidal and U-like magnetic circuit, around which the copper wire windings are concentrated . Depending on the functional qualities, the density of the wire on them also changes.

• Spot. The welding area is heated by two copper electrodes and is subjected to high pressure. The design contains capacitors. The transformer has copper contacts. The components to be welded are concentrated between them. The power of transformers here is inferior to point 1. They also have a U-like core.

Whatever model you plan to create, you need to know its characteristics and how they can be varied.

How to assemble a transformer for welding copper wires with your own hands

If for some reason purchasing a device is not an acceptable option, you can build this equipment yourself. The basis for it is an old transformer.

Preparation of tools and materials

To create the planned device you will need the following arsenal:

• Transformer.
• Finished box or casing.
• Electrical cable.
• Pliers.
• Device for holding the electrode.
• Carbon electrode.
• Automatic or semi-automatic devices.

To make step 6, you can use the core of a massive round battery or a large carbon brush.

It is necessary to assemble a homemade device only if you have good knowledge of the circuitry and operation of such devices.

As a base, you can use transformers from unused old TV sets, microwave ovens, etc. The base power should be 200 - 500 W.

Build process

It goes through painstakingly, the turns are scrupulously counted. The following is an example of creating a device with a P-like core. This process is much simpler than toroidal modification structures.

Stages of work

Frames for windings. They are created from textolite plates, from which elements for a pair of boxes are cut. Each box has two top lids with slots into which four walls are placed. The area of ​​the slots inside is identical to the cross-section of the core. At the same time, the dimensions of the walls of the box increase insignificantly.

• Insulation of frames with heat-resistant material.
• Winding windings.

The wires for them must have heat-resistant glass insulation. After winding one layer, insulate it and make the next one. Taps are created on a certain number of skeins. In the final phase, the top insulation is wound. The ends of the wires are pulled through holes made in the topmost plate. Copper screws are then secured to these ends.

• Assembly and lamination of magnetic wire. Here, iron plates from outdated transformers are used. Their thickness is 1 mm. They are assembled into a monolithic structure. At the end, all windings are tested for defects by a tester.
• Creation of a diode bridge. Diodes B200 or KBPC5010 are used. Each of them is designed to operate with a load of 50 A. If your device has a parameter of 180 A, you need 4 such diodes. They are fixed to the radiator. Their connection to the windings is parallel.
• Housing assembly. Place a transformer there.

Rules for welding copper wires

One of the common causes of fires is faulty electrical wiring. Fires occur due to insulation failure or heating of cable cores at connection points (sockets, switches or junction boxes).

Poor contact leads to the appearance of a large contact resistance, which generates heat. This destroys the insulation, causing a short circuit and fire.

Therefore, obtaining a reliable, high-quality connection of copper conductors is a prerequisite for the safe operation of any household electrical appliances.

Using an inverter

Copper wires, most common in residential buildings, are connected in several ways, but welding is considered the most reliable. As a result of this connection, a homogeneous conductor is obtained, which ensures complete fire safety.

Welding is carried out with direct or alternating current voltage from 12 to 36 V, and the welding current must be adjusted. Most welding inverters meet these requirements.

They produce a special apparatus for welding copper wires, which is used by electricians. It has a power range of 1-1.5 kW and welding current adjustment in the range from 30 to 120 A.

Unlike conventional inverters, the equipment has less weight and dimensions; in addition, the ends of the welding cables are equipped with a special holder for carbon electrodes and a clamp with a large clamping surface for the conductors.

If the farm already has an inverter welding machine, then you don’t need to buy a special device for welding copper wire.

For convenience, pliers and an electrode holder are welded to the welding cables or attached through a bolted connection. Any powerful clamp can play the role of a carbon electrode holder. Its handles must first be insulated.

The pliers are attached to the ground wire. They will hold onto the twist of the copper conductors being welded, while they will perform the important function of heat removal. This is necessary to protect the insulation from exposure to high temperatures.

Contact method

In addition to using an inverter for welding copper wires, spot contact welding can also be used, the welding time of which does not exceed 1-2 seconds.

At home, to connect household electrical wiring, you can use a conventional 500 W transformer with a voltage in the secondary winding of 12-36 V. By attaching a holder for the electrode and copper wires to the secondary winding, we get a simple welding machine.

Depending on the cross-section and number of copper wires, it has been experimentally established that the current for welding should be:

• for 2 wires with a cross section of 1.5 mm2 – 70 A;
• 3 sections 1.5 mm2 – 80 A;
• 3 sections 2.5 mm2 – 90-100 A;
• 4 cross-section 2.5 mm2 – 100-120 A.

However, current values ​​can vary greatly depending on the cable used and its manufacturer. The fact is that cable manufacturers use copper wires with various impurities, which affects electrical and thermal conductivity; wire cross-sections sometimes do not correspond to the declared characteristics.

Therefore, spot welding is carried out only after the optimal welding current has been adjusted on scraps of the same cable that is to be welded.

Procedure

When welding wires with your own hands, the procedure will be as follows. First, you need to remove the insulation from the ends of the conductors to be welded to a distance of 8-10 cm.

When removing insulation, do not damage the wire cores. Before twisting, they must be cleaned with sandpaper and wiped with acetone to degrease.

Then the copper wires to be connected are twisted and the ends are cut with wire cutters so that the end of the twist is flat. The result should be a bunch about 5 cm long.

The preparatory work ends here, and the welding itself begins. The ground clamp of the turned on welding machine is attached to the twist, and a graphite or carbon electrode is brought to the end of the twisted conductors, which is held at the end of the second welding wire using a special holder.

As a result, a short circuit occurs with the formation of an electric arc. Its energy is enough to melt the ends of copper conductors in 1-2 seconds.

A molten drop of copper forms at the end of the twist; it needs to be given time to cool. After this, the twisted area is insulated with tape or heat-shrink tube (the tube must be put on in advance).

The welding joint is of high quality; its electrical characteristics do not differ from those of the entire copper wire, and will last no less than it.

Electrodes used

To weld copper wires, carbon or graphite electrodes with copper plating are used. Their characteristics are almost the same.

They have a melting point three times higher than that of copper, due to this, electrode consumption is minimal; are easy to cut, which allows you to obtain a length convenient for welding.

Carbon electrodes produce an arc of higher temperature than graphite electrodes, which allows them to be used at minimal welding currents. They are also convenient when using homemade low-power welding machines.

Welding with graphite electrodes is often used with inverters that have current control over a wide range and are undemanding to the welder’s qualifications. In addition, the copper welded joint is of higher quality.

Externally, the electrodes differ in color - coal black, and graphite dark gray with a metallic tint.

If you don’t have factory electrodes at hand, then when welding they can easily be replaced by brushes from an electric motor or a carbon rod from an old battery.

Source: https://svaring.com/welding/detali/svarka-mednyh-provodov