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.

Welded copper wires

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 a short-term heating to +1080 0 C is required. Work must be performed when connected with straight polarity, since under such conditions a stable arc burns.

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.

Inverter for welding

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:

• 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.

The following electrodes can be used for welding copper conductors:

• carbonic;
• graphite.

The carbon electrode has a number of the following features:

• the temperature at which melting occurs is +3800 0 C;
• work is performed on direct current with straight polarity;
• relatively low arc efficiency;
• it is permissible to carry out 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.

Electrodes for welding

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.

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.

Copper melts well and is quickly saturated with hydrogen and oxidizes in the molten state. The melting point of copper alloys is no more than 1000°C. To protect the metal when welding copper parts, argon or carbon dioxide is used, but welding wires in a protective atmosphere is not economically feasible. For welding copper cables, conventional machines are used that generate direct or high-frequency alternating current and voltage from 15 to 30 V.

It is desirable that the operating current be regulated; to twist one core with a cross-section of 1.5 mm2, a current of 70 A is needed; to connect three wires, the amperage will need to be increased to 90–100 A. To install copper wiring in a house with the connection of powerful electrical equipment, it is necessary to select welding machines up to 120 A. If there is no optimal current, the arc will be interrupted and the electrode will begin to stick.

Soldering or welding copper wires - which is better?

The easiest and most effective way to solder 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, 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.

Inverter

The advantages of modern ones are obvious:

• they can weld wires of any cross-section;
• they are not afraid of voltage “sagging” in the network, they reduce the risk of electrode sticking and burning of copper strands;
• there are lightweight models that deliver current up to 150–200 A;
• operate from a standard network, no need to connect to three-phase current.

Working with an inverter is easier than working with a transformer. For direct current welding of direct polarity, the plus is connected to the electrode holder, the minus to the copper wire being welded.

Transformer

Bulky old-type devices are difficult to drag from place to place, but transformers are capable of generating current within 400 A. The transformer is suitable for working with direct current of direct or reverse polarity. They are used for welding copper busbars in distribution panels and connecting twisted conductors of large cross-section. The transformer is connected in the same way as an inverter: “+” to the electrode, “-” to the twist. Transformants have good performance, but during operation they hum a lot, get hot, they are periodically turned off and allowed to cool. When turned on, they “sag” the network, but then the voltage stabilizes. When working with a transformer, this should be taken into account.

Based on a step-down transformer with a power of up to 150 A with a voltage from 12 to 38 V, you can make it from household appliances: you need to wind the number of turns of cable around it. You can calculate their number using tables. If you include a diode bridge in the electrical circuit, it will stabilize the arc. The holder can be purchased at the store or a trolleybus contactor clamp can be used instead. Clamping conductive pliers are made from pliers - a contact terminal is screwed to one handle. Be sure to ground the homemade device.

Technology for welding strands of copper wires

The connection consists of melting the welded conductors with an arc while passing current, the clamping device compacts the structure of the diffuse layer. It is worth considering the process of welding strands of copper conductors in more detail. Step by step instructions:

1. The ends of the cable to be connected are cleaned and the insulation is removed at a distance of up to 7 cm so that the wiring is not damaged during operation.
2. The cores or threads are folded in parallel, they must be tightly twisted together, the type of twisting does not matter, but when axially joining in the direction of the conductors to each other, it is more difficult to weld the twist.
3. The length of the twist should reach 5 cm, excess fibers are cut off. The wires are placed between the contacts or in a homemade clamping device at a distance of 2–3 cm from the edge.
4. After touching the conductors with the electrode, an electric arc occurs; it is held for no more than 2–3 seconds, depending on the thickness of the conductors.
5. The copper is melted in the clamping device, creating a strong connection.
6. The cooled connected conductors are wrapped with insulating tape or heat-shrinkable film is put on it.

• for connecting conductors with a cross section of 1.5 mm 2:

- twisting of two wires - 70 A;

- out of three - 80 A;

• with a cross section of 2.5 mm 2:

- twisting of three wires - from 90 to 100 A;

- out of 4 - from 100 to 120 A;

• for connecting 5 mm cores, the maximum current is no more than 150 A.

Before installation work, it is advisable to practice on cable scraps. You can tell that the copper has melted by the red bead at the end of the conductor.

Selecting Electrodes

The arc is ignited with a carbon rod or a copper-plated graphite electrode, also called a “graphite pencil”. The arc of a black carbon rod is higher than that of a gray “graphite pencil”; the consumption of electrodes is small.

If there are no carbon electrodes, craftsmen use graphite cores of AA batteries.

When welding cable joints, it is necessary to take care of individual protection against electric shock; do not neglect grounding. It's best to keep a fire extinguisher handy.

High-quality connections of copper wires in electrical wiring - guarantee of safety and long service life.

For connections, twisting, soldering or welding are used. The welding connection surpasses all others in reliability. And the process of welding wires is possible using a special apparatus.

Electrical copper cables consist of several cores, each of which is twisted separately. During repairs, work has to be carried out directly in the junction boxes, which causes certain inconvenience. In order to solder each twist along the length with a soldering iron (a point connection will not be enough) at a height, you will have to spend a lot of time and effort. By welding, it is enough to connect the wires only at the end of the twist. And the compact devices used during the work facilitate the process.

Welding copper is complicated by the fact that it becomes brittle already at 300°C, and melts at 1080°C. Therefore, in addition to theoretical knowledge, it is necessary to have work experience. For those who are faced with the need to weld contacts in a distribution box for the first time, it is recommended to practice on prototypes.

Twists of copper wires can be welded or using a homemade device based on a step-down transformer. Electricians use a highly specialized machine designed specifically for welding strands. The operating procedure does not depend on the selected device and is as follows:

1. Remove the insulation from the wire to a distance of about 100 mm.
2. Make twists of the required cores. The length of each should be about 50 mm.
3. Attach the mass next to the twist.
4. Apply the electrode to the wires until an arc forms. Contact – 1-2 sec. The twist is welded.
5. Cook the next twist after the previous one has cooled.
6. All that remains is to insulate each twist using heat-shrinkable tubing or electrical tape.

The current required for welding wires is usually 30-90 amperes and depends entirely on the number of wires in the twist and their cross-section, as well as on the actual voltage of the supply network. The welding machine must have a current control function. Work is carried out at a voltage of 12 or 36 volts. As an electrode when welding wires, the ideal solution would be to choose carbon containing copper.

Don't forget cut off the power welded wires!

Brief overview of devices

Specialized devices TC 700 produced by Prizma are used exclusively for welding strands of copper and aluminum(in the second case, using flux). They are simple and easy to use. The very compact dimensions of the device and light weight, as well as the simplicity of the welding process itself, are exactly what is needed for such painstaking work. The device produces an output voltage of 12 V, and the power consumption during operation is from 1 to 1.5 kW (depending on the modification). A simplified model for household needs, TS 700-1, for electricians, TS 700-2, and for large-scale production, TS 700-3, is produced. They are equipped with two power cables, one of which is equipped with pliers for clamping twists, and the second is equipped with an electrode holder. There is a portable bag with a shoulder strap. The household model welds twists up to 16 mm in diameter, the other two – up to 24 mm. The price of the first is 7600 rubles, the second 8950 and the third 9300.

How to choose a device

In any case, the main guideline for choosing a device is is the purpose of the acquisition, price and functionality. For domestic purposes, purchasing a specialized device for welding copper is hardly advisable. It is better to rent such a device for a while. But if you often have to weld wires, then, of course, a special machine is simply necessary.

It is more profitable to purchase for a home universal inverter device. With the help of which you will be able to perform any required welding - the range of their capabilities is unusually large. Another question is. that welding twists will require some knowledge from you, but this can be fixed.

When selecting a welding inverter, pay attention to the power and power source. An overly powerful device is a luxury. A model with a power of 4-5 kW is quite suitable for home.

Of the desirable functions that significantly facilitate the welding process, it is desirable to have "hot start", protection against sticking and insensitivity to power supply voltage changes. A current of up to 160 A allows you to weld metal up to 5 mm thick, which is usually quite enough for domestic purposes.

inverter models are the best choice. They are easy to use, allowing a beginner to quickly master the basics of welding.

The disadvantages of welding inverters include high cost and interference in the network.

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

In the household of a craftsman there will always be an old unused transformer, on the basis of which you can make a home welding machine for copper wires. The circuit diagram of the device is simple; any beginner can handle the installation. For production you will need:

• Material for the casing or finished box;
• Electrical cable;
• Pliers for clamping twists;
• Electrode holder;
• A carbon electrode, which can be made from the core of a large coin cell battery or a large format carbon brush.
• Slot machines or

A homemade device and a story about it in the video below

It is permissible to engage in the manufacture of homemade devices only if you are well acquainted with concepts of the operation of electrical devices. There are a lot of detailed descriptions of homemade structures; below are photographs of some of them. Transformers can be used from old TVs, from microwave ovens, and others. Sufficient transformer power for making a welder lies in the range of 200-450 watts.

The assembly diagram is shown in the figure:

The good thing about this home appliance is that it does not require significant investment of money, and its functions are sufficient to solve everyday welding problems.

Follow safety rules when working with electrical devices! So, under no circumstances, do not connect the transformer from the microwave oven to the network for testing! The voltage on the original secondary winding reaches 2000 V! Only after its removal is it possible to use such a transformer for our purposes, and the secondary winding will have to be made independently.

Another homemade device and a story about it

Parameters of welding work with copper

The choice of current strength specifically related to the diameter of the twist, the number of wires in it and their cross-section is of paramount importance for a quality result. The best values ​​are selected empirically and professional skills play a major role in this. For a rough guide to the values, below is a table of recommended parameters.

Vacuum brewing

There is a method of welding copper using electron beams in a vacuum. Required for operation special apparatus and vacuum chamber. This method is applicable only in equipped production workshops or laboratories.

Copper wires are most often used to make electrical wiring. The aluminum analogue is practically not used. Welding of wires made of copper is done using not only alternating current, but also direct current. Its voltage is within the following range: 12–36 V. In this case, the current supply must change. Welding wires with an inverter has its own characteristics.

Inverter type devices

The advantages of inverter units are well known to specialists. Certain models are equipped with a strap that allows you to carry the inverter on your shoulder. This makes it possible to carry out welding work with twisting in a junction box while standing on a stepladder. The inverter can be connected to household electrical wiring, since the device has low power consumption.

Inverters have a wide range of electric current regulation. Their arc is very stable and ignites perfectly at low welding currents. For this reason, even an untrained electric gas welder can quickly achieve an amazing effect and achieve optimal quality of wire welding.

Household welding devices are marked with the abbreviation MMA. Then numbers are indicated indicating the operating current - 200 or 250 V. The professional device operates in a temperature range of up to 150 degrees. The home device has a spectrum from 0 to +30. Another difference between a home device and a professional and industrial device is the duration of the operating cycle.

A professional type inverter will operate for 8 hours with short breaks, an industrial type - 24 hours with a break of 30 minutes. The device, intended for domestic use, operates without interruption for 30 minutes, and then cools down for an hour.

When welding a copper type cable, a special copper-plated carbon electrode is used, which is popularly called a “pencil”. If you don't have a carbon electrode, you can take a standard carbon rod from an unusable battery. Welding current, depending on the cross-section and number of wires, is used at different voltages. A suitable mode is one in which the electrode does not stick to the welding area and the arc is stable.

Process

Welding of wires is carried out using technology, thanks to which an optimal result is obtained. Welding wires with an inverter is carried out in stages:

• It is necessary to strip the cable of external insulation.
• Then they make a twist, cutting it so that the ends of the wires are at the same level, while the minimum twist length should be 50 mm.
• Then you need to install a copper clamp that removes heat and turn on the inverter.
• Bring the tip of the charcoal pencil to the finished twist, clamped in the holder, and connect the wires by welding.
• After a few seconds, a small ball of molten metal will form at the end of the twist, after which the work is stopped. To prevent the insulating shell from melting during operation, work with each twist for no more than 2 seconds.
• After the cable has completely cooled, the wires are insulated using ordinary insulating tape or heat-shrink tubing.

Specifics of welding work with aluminum wires

The most reliable method of welding the twist end is considered to be the spot method. The advantage of this method is that during welding, the metal of the conductors merges. And if with other options a transition resistance of the contact area may arise, then with the point mode this does not happen. Electrically welded wires are durable and do not require periodic maintenance, inspection or repair.

Possible complications of work

When working with aluminum cables, a number of difficulties arise:

• It is difficult to make a high-quality connection due to the oxide film that rapidly forms on the metal. This makes it difficult to obtain a uniform connection of wires.
• The increased fluidity of aluminum in the molten state makes it difficult to achieve good quality welds when welding tight joints.
• Metal shrinkage should be taken into account. But the obtained result can always be improved with additional twist processing.

Handling aluminum cable at home is a difficult task. The correct welding mode must be carefully selected. There is a misconception that inverters have a constant output voltage.

In fact, the device is equipped with an electric current control and the voltage can be lowered, depending on the diameter of the wire:

Voltage,B	Diameter of wires, mm
25	0,5–1,0
20	0,3–0,5
12	0,1–0,3
10	0,05–0,1

You should also choose the correct diameter of the electrode, depending on the area of ​​the core:

The magnitude of the welding electric current varies depending on the number of wires and their diameter:

When welding with alternating current, it is difficult to achieve a good result and it takes a lot of skill to get a quality connection. That is why a non-professional will need a good device to master the basics.

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 - relatively high 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.

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.

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.

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 finger-type or larger battery, 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 the twist, 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.

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.

Welding machine

The main feature of the copper wire welding technology is the time interval of one to two seconds. If the process takes longer, the heat has time to reach the base of the twist. The consequence of this is heating and destruction of the insulation. For this reason, the welding fixture must have sufficient electrical power. Minimum value 500…1000 W. And for optimal arc ignition, it is recommended to select a voltage from 25 to 36 V.

The quality of welding depends significantly on the quality of the voltage. Alternating voltage is simple from a technical point of view, but the result is the worst. But this is in welding theory, when you need to hold the arc and weld a high-quality seam. And for a process that lasts only a couple of seconds, there is no point, as they say, to fence the garden. For all wire formats used for electrical wiring, a two-kilowatt transformer with a 36-volt secondary winding is the best option.

A very good result can be obtained by using two car batteries connected in series. Within half the discharge, they produce significantly higher currents compared to transformers of similar mass. Considering that welding can be done in a room to which there is no electricity, the battery option is unrivaled. And since these batteries can be used both in a car and for spot welding, it probably makes sense to spend money on them, and not on a specialized powerful transformer.

1.5 sq. mm > 70 A,

2.25 sq. mm > 80 A,

2.5 sq. mm > 100 A,

5.0 sq. mm > 120 A.

Precautions

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.