Diesel Welding Generators: An Overview of Diesel Power Plant Models. How to choose for welding

What it is?

This device is a mobile power station equipped with an internal combustion engine (ICE), which produces electricity in an autonomous mode for arc welding or cutting. Simply put, this is a two-in-one unit - both an electric machine (generator) and a welding inverter that does not require connection to the electrical network.

At the same time, the installation itself can easily be used not only for electric welding, but also when there is no electricity at the facility as an autonomous power plant. The device will also come to the rescue when there is an unstable electrical voltage in the network, and an ordinary inverter is simply not able to start.

This type of equipment as such is quite simple and convenient, as it functions without any kind of additional devices. In essence, this is a simple gasoline or diesel engine and an electric generator. By burning fuel, the motor forces an electric generator to function, which produces direct current.

Experts do not recommend practicing ordinary home modification to power the welding machine, since the electric current it produces may not be enough for electric arc welding. Although the principle of action is similar. In addition, it is necessary to distinguish between a welding generator and a welding unit. The latter is a combination of 2 independent options in one shell. It can be practiced on its own as a source of electricity or additionally use the welding option without being connected to the mains.

Review of popular models

To understand how the features of working with a welding inverter affect the appearance, weight, price and versatility of generators for electric welding, consider several manufacturers of popular models of gas generators. The Japanese firm Honda originally specialized in the production of motorcycles. This determined the company's rich experience in creating compact, lightweight, but at the same time powerful and reliable gasoline engines. Gradually, the corporation has built a solid reputation in the market for passenger cars, aircraft engines and stand-alone generators.

Japanese gas generators are renowned for their quality and reliability. But the prices for them are rather big. For example, the model "EP 200 X1 AC" has a (electrical) power of 6 kW. This is sufficient for most welding jobs. The “intelligent” inverter provides flawless maintenance of 220 V voltage and 50 Hz frequency, which allows the generator to be used to power any household appliances. The cost of such generating stations starts from 130 thousand rubles.

The domestic manufacturer also offers gasoline generators for electric welding. Among professional welders, electric generators and TSS inverters are gaining more and more popularity (sometimes this brand is mistakenly searched for by typing the abbreviation TTS). The TSS group of companies unites both trade organizations and factories that produce welding equipment, automation and autonomous power generators.

For example, the popular TSS GGW 4.5 / 200E-R welding generator has an output of 4.5 kW. The four-stroke air-cooled motor combines compactness and high efficiency. Starting the engine is possible both with a manual starter and from the battery - by pressing a button on the remote control. Such units cost from 55 thousand rubles. For work in a stationary workshop, the TSS PRO GGW 3.0 / 250E-R generator set may be the best choice. Such a unit was originally designed for welding - it contains an inverter welding machine.

Long-term operation with electrodes up to 6 mm in diameter is permissible. In addition, the gas generator has sockets for powering household consumers of 220 V (up to 3 kW) and even a car battery charging station! At the same time, the price - from 80 thousand rubles - makes the device quite affordable for the mass consumer.

Popular models

On many construction sites, there is a need for permanent and reliable connections that require an electrical current of approximately 200 A. Such requests completely overlap 220 V generators.

We present especially demanded samples for 220 V.

Fubag WS 230DC ES. The equipment has a sturdy metal tubular frame, powder-coated for long-term resistance to rust formation when working outdoors. The maximum welding electric current is 230 A, and a volumetric fuel tank of 25 liters is enough for a long-term process for 9 hours. In this case, welding can be carried out on an electric current of 150-160 A. The installation steadily generates 220 V and transforms it into a constant voltage. There is an electric starter for a comfortable start.

For serious construction, where thick metal is used, more powerful equipment is needed that is capable of conscientiously boiling metal or cutting. See an overview of popular 380 V.

Mosa TS 200 BS / CF 27754. If a 3-phase power source is required at the workplace, but the necessary funds for a powerful unit with many functions are not available, then the choice falls on this device. It generates a constant voltage with an electric current of 190 A for 3 phases. The equipment from Italy is provided by a Japanese Honda motor. Only the cost was reflected in the functionality and equipment. But the manufacturers endowed the device with a decent power - 8.3 kW.

Generator for mobile inverter

Due to the use of modern inverter technologies, the design of the welding unit has been significantly lightened, and its dimensions have decreased several times. At the same time, the mobility of such a device has also significantly increased, which is explained not only by the compactness of the device itself, but also by the possibility of its operation from an independent generator source.

Important! In conditions where inverters for a generator are a normal load, it was possible to implement a mode in which electronic equipment operates without being tied to the mains. A typical generator for an inverter-type welding machine is traditionally made in the form of a gasoline engine with a drive that provides electrical energy.

Everyone who at least occasionally visits the forum on the relevant topic should be aware of how topical the issue of switching to a mobile inverter is.

A typical generator for an inverter type welder is traditionally made in the form of a gasoline engine with a drive that provides electrical energy. Anyone who at least occasionally visits the forum on the relevant topic should be aware of how topical the issue of switching to a mobile inverter is.

At the same time, many of the interested users who very often visit this forum ask themselves a natural question about which generators will pull the inverter welding machine. The answer for all those interested in this problem is the calculations and calculations given in special sources, with a summary of which can be found in the following sections.

Note! The possibility of using a gas generator for a welding machine is also attractive for those who often have to work in the field, away from power lines. Note that in urban conditions, stationary welding equipment operates from mains voltage sources, the stability of which can be no doubt (see figure below)

Note that in urban conditions, stationary welding equipment operates from mains voltage sources, the stability of which can be no doubt (see the figure below).

Inverter in the workshop and in production

In the field, when a gasoline generator is needed for a welding inverter, there is no and cannot be complete confidence in the stability of the power supply. To avoid this inconsistency, it will be necessary to calculate in advance the generating system for its ability to provide the specified performance characteristics (what current is needed at its output, for example).

The decision on how to choose a generator for welding machines depends on a number of criteria, the main of which are:

The power of the welding inverter (or the current consumed by it);
Operating conditions (normal or critical);
The characteristics that the gasoline generator itself has.

The main requirement in this case for the generator set is its operating power. In the next section, we will get acquainted with how this parameter is calculated, and which generator is better to choose based on its results.

What is the choice based on

A large number of diesel welding power generators are currently on the market. Previously, only high power diesels were offered. Now you can buy diesel machines with a capacity of 2 kW.

Such a wide choice baffles some. In order to make the right choice, you should think about what materials you will have to deal with. What thicknesses of metal will you have to weld? How often will you have to work and for how long? What are the mobility requirements?

Having decided on these questions, you can start choosing a manufacturer. For example, you need to work with metal with a thickness of 2-10 mm. It requires an electrode up to 4 mm in diameter. They work with such electrodes at currents up to 160-200 A. This means that you need to choose a diesel generator with a welding current of at least 160 A.

If it is supposed to work with carbon steels, aluminum or stainless steel, then it makes sense to use a generator with an output alternating welding current. The price of such a device will be cheaper than a DC device.

Species overview

Depending on the fuel, generators for welding can be gasoline or diesel. Let's consider each in more detail.

Gasoline

Among folk craftsmen and professional welders, this type of generator is especially in demand. It can be equipped with a 2-stroke or 4-stroke petrol engine. The device has a low power and is used for work with light loads. In addition, the gas generator is characterized by improved parameters of electric current, which have the best effect on the quality of the welded seam.

The power of gasoline samples ranges from 2.5 kW to 14 kW. The gas tank capacity of such devices is also small - approximately 4-25 liters. Such generators have the ability to generate the ultimate electric current on a scale of 160 to 300 A and are capable of operating with electrodes up to 5 millimeters in diameter.

The advantages of gasoline devices:

reasonable price;
light weight (from 50 to 100 kilograms);
ease of use;
the ability to start and operate in conditions of low ambient temperature.

Disadvantages of gasoline devices:

short service life (from 500 to 3000 hours);
impressive fuel consumption, for example, a 4 kW unit burns approximately 1.7 to 2.4 liters of fuel per hour;
the unit needs to be given a break after a set time (noted in the manual for the device).

Diesel

Diesel generators make it possible to carry out welding operations with solid loads and have an impressive indicator of durability. Diesel devices are not suitable for household needs, since they have a power of 6 kW to 16 kW and are expensive. Stationary units can have power up to 80 kW.

The advantages of diesel generators:

service life of approximately 40,000 hours;
stability of work;
metal welding at increased loads;
high efficiency;
at a power of 4 kW, less fuel consumption compared to the gasoline version of the generator - approximately 1.6 liters of fuel per hour;
the diesel plant can operate without respite almost around the clock.

Disadvantages of diesel installations:

the motor is not easy to start in low ambient temperatures;
large mass (from 100 kilograms or more);
high price.

Criterias of choice

Many users have enough information that during the operation of a fuel generator it is possible to obtain electrical energy. Professionals, however, distinguish for themselves separate categories of such devices, among which gas generators for welding and their diesel analogues are in the same row. However, it is impractical to consider these generators as a separate type of devices that generate electricity from a fuel resource.

The principle of operation of the welding gas generator is not much different from the usual household counterparts used on the farm. The key essence of its action is that at start-up, a welding arc is ignited, through the winding of which an electric current flows, sufficient to maintain the arc burning process.

The process of generating current itself is quite simple. An internal combustion engine is hidden inside the generator. This mechanism involves the rotation of the internal crankshaft with the transformation of mechanical energy into electrical energy.

However, the technical simplicity of the process of generating power for welding is not all there is to know about such equipment. When choosing a high-quality gas generator for welding, you should rely on more weighty criteria.

Naturally, the generated power of the generator should be selected in comparison with the consumption of the existing welding machine. If the last value is not in the technical documentation, then the consumption can be calculated by multiplying the maximum welding current with the arc voltage and dividing this value by the efficiency of the welding inverter.

It is also worth noting that there are more nuances in the combination "welding unit - generator" than just "buy with a margin", and therefore, when choosing one device for another, you should make a detailed consultation with a specialist.

Varieties and power

Gas generators are classified according to their capacity:

The generator for domestic conditions (from 0.7 to 5 kW) is a mini-power plant that allows you to power household appliances, is compact and easy to transport. In general, gasoline generators for welding under conditions of high mobility and for spot distribution of objects are excellent.
A synchronous generator (from 5 to 10 kW) is a more versatile source of electrical energy, which, with its power, allows you to work with both welding equipment and household appliances. It is quite possible to power one country house / plot.
A welding generator (from 10 to 20 kW) is a full-fledged welding complex, which intelligently combines a generating generator set and an inverter. As a rule, due to its size, a gasoline generator with a welding function is used stationary, but it can also be made in a portable format.

Above, the power of the gas generator has already been determined by the key criterion for its selection. The calculation of this value when choosing the correct welding machine is carried out as follows:

We find the limiting level of current consumption by the inverter (Imax). For example, Imax = 21 A. Information can be printed on the case or recorded in technical documentation.
The power of this installation can be calculated according to Ohm's law, multiplying the voltage by the obtained Imax value. In the described case: 220 V * 23 A = 4620 W.
Over the obtained value, we throw in 30% of the power reserve. 4620 + 1386 = 6006 W.Thus, the optimal power level of the generator should be at least 6 kW.

Peculiarities

A modern diesel welding generator is useful for work in areas where there is no stable power supply (or at least some kind of power supply). Using this device, you can equip water supply, sewerage, heating, gas and oil pipelines even in the most remote places. For obvious reasons, diesel welding generators are also useful in eliminating accidents, when working on a rotational basis. The current generation can also be used for emergency power supply. Therefore, similar generators are needed as emergency energy sources.

They are arranged relatively simply. There is an electric current generator driven by an internal combustion engine. They are mounted on one chassis. The connection of the two main units is made either directly or through a reducer. In some models, the generated current is fed to a step-down transformer. To compensate for the effect of various factors on the amperage (which determines the quality of welding), manufacturers offer inverter-type generators.

And only pulse discharges are fed to the step-down transformer. A direct current can be re-formed at the output. With all the advantages of such a solution, it obviously increases the cost of the structure.

Welding generators can be made according to a single-phase or three-phase scheme. In the first case, medium-sized devices are obtained that are useful in various workshops, in the course of ancillary work. Three-phase systems are needed when it is required to provide the work of several welders at once. Regardless of this, diesel machines are better than gasoline ones for long-term current generation. They are also characterized by increased efficiency and general practicality, much more reliable than carburetor generators.

Power selection

What power generator should I choose for domestic use, for example with an inverter, which is considered the most popular device? If it is not possible to purchase an inverter station, then you can limit yourself to a universal generator.

For household welding, as well as for all household needs, a power of 5-10 kW is enough. The maximum output current should be 200-250 A, voltage - 220 V, frequency - 50 Hz.

The main rule when selecting: the power of the generator should overlap the power of the inverter by a quarter. Only in this case, the latter will be able to deliver a stable welding current, and will not fail after a couple of months of use.

This refers to the generated power of the generator, not consumed. In addition, the parameter of the maximum power consumption must be taken into account separately - this is the peak load of the inverter.

So, the generated power of the generator should be 25-30% higher than the maximum power consumption of the inverter. These data must be indicated in the passports of both devices. If only the maximum welding current and arc voltage are indicated for the inverter, then the power can be calculated by yourself:

P = U * I / device efficiency.

The efficiency of the inverter is on average 0.85. This figure must be indicated on his passport.

Suppose the operating voltage of its arc is 20 V. The maximum current is 200 A. Using the formula, we get that its maximum power consumption is 4706 W.

Thus, the constant power that the generator must generate should be 5882.5 W (approximately 6 kW) - a fairly powerful device.

Is it better to select the welder and generator separately or buy a welding generator?

A welding generator is a construction of a gas generator and a welding machine paired with it. The power plant is designed in such a way as to serve exactly the welding, therefore, it has a longer service life. Other advantages should be noted:

Installed protection against short circuits;
It is possible to work in corners remote from the central power supply (outskirts of the city, field, road);
The design is more compact than if you connect the welding separately;
The cost is lower than that of a diesel generator of a similar power.

Disadvantages:

Such a generator can only be used for welding;
Gasoline has more fuel consumption and is more expensive than diesel;
Cannot be powered from a central network;
Low service life.

The most significant limitation is that it cannot be used as a backup power source for other consumers. It is intended for welding only.

A welding generator is the best option if you are professionally engaged in repair work, constantly going to open places without access to electricity. You don't have to connect or set up anything - just start the engine and adjust the current to match the electrode diameter. Less wires and easier to manage.

But, on the other hand, this way you will not be able to connect the structure to the central network. The average consumption of gasoline is 0.5-0.6 l / kW * h, and this will cost 10 times more than when the device is connected to the central network. In addition, with such a consumption, electric generators have limited autonomy. On average, it is only 3-5 hours.

How to choose a generator for welding?

The first thing you need to pay attention to is the power plant rating. It is selected according to the maximum power of the consumer

It is best to take with a margin of 25-30%, because frequent use at maximum load will increase wear on parts.

How to calculate the power of a generator?

You can calculate the power using the formula: P_nom= I × U_arcs / η, where I is the maximum current of the apparatus, U_arcs - electric arc voltage, η - welding efficiency. The values of U and η are almost always stable, the arc voltage is 25V, and the efficiency is 85% on average.

For example, if the maximum current of your device is 150A, then its maximum power consumption will be:

150A × 25V / 0.85 = 4412W.

Rounding off, we get 4.4 kW. Now let's add another 25% of the stock:

4.4 kW +1.1 kW = 5.5 kW.

This is the nominal value you need for 150A.

Can a smaller generator be used for inverter welding?

The inverter allows you to adjust the amperage. And it can be powered from an electric generator of less power than the nominal, but before that you need to find out the limit level of the current strength.

And so, let's imagine that you have a 225A inverter, but an electric generator of only 4 kW. Now let's make a calculation using the inverse formula: I = P × η / U;

The limiting current strength of the inverter at which you can connect it to a 4-kilowatt generator is:

4000W × 0.85 / 25V = 136V.

Thus, you can set the threshold to 136V on the inverter and freely use the 4 kW power supply. But, if you put a higher current strength, the alternator will burn out and it will have to be repaired.

Power selection by electrode diameter

Larger electrodes require higher amperage. That is why there is a relationship between the network load and the diameter of the electrodes. And so, let's see the table:

Electrode diameter
Minimum generator power

2 mm
2.5 kW

3 mm
3.5 kW

4 mm4
4.5 kW

5 mm 5
5.5kw

For example, if your inverter welding is powered by 4.5 kW, then the largest electrodes with which you can weld metal are 4 mm. If, for example, you insert a 5-mm electrode, then 4.5 kW power will not be enough for high-quality metal melting, and the seam will be of poor quality or not welded at all. Therefore, the autonomous power supply must be selected primarily according to the maximum power of the inverter.

Not all welding machines can be powered by an electric generator and vice versa. Therefore, before buying, check with the seller if the selected welding model can be operated from a power plant. The manufacturer always indicates this in the instructions.

Which manufacturers are suitable for welding machines?

Based on the specifics of the application, not all manufacturers produce power plants for welding machines.Most suitable brands:

AGT - mainly "three-phase" with a rated power of 5 kW. Cheap, gas generators are equipped with original Honda engines. According to the technical characteristics and fuel quality requirements, they are adapted for the Eastern European region. Manufactured in Romania;
Endress - produce single-phase and three-phase gas generators with a rated power of 3 kW. Inside there are high-quality engines from Honda, Briggs & Stratton, Yanmar, Kohler. Massively produced in Germany, do not have chronic problems. Good brand reputation;
R.I.D. - produces both single-phase and three-phase power plants with a capacity of 5 kW. Produced according to the technologies of the German brand Geko. Produced in small quantities. The cost is higher than that of competitors, but the quality leaves no question. Reliable engines.

If you do not have a welding machine yet, as an option, you can purchase a special welding generator instead.

Exploitation

Achieving the maximum possible performance of devices and extending their service life depend on correct operation, whether it is a do-it-yourself welding generator or an industrial gas generator and a welding inverter.

The peculiarities of using welding stations primarily depend on their format. These can be industrial, household, or professional devices.

The use of equipment of the first type in large-scale or industrial production presupposes that the device has a wide range of capabilities that allow for manual, semi-automatic, and other types of welding.

An industrial type generator requires proper maintenance to operate. Customizers and process engineers are responsible for this. The latter, among other things, are developing unique methods of joining.

The most common welding method is manual. Of course, in the ideal case, the owner of the said apparatus is an experienced welder. Nevertheless, quite often a person becomes a professional after purchasing the unit.

Connecting a diesel generator.

When using a generator, you must follow a few simple rules:

use the device on a horizontal plane;
as the first parts to be welded, it is better to use workpieces with a thickness of three millimeters;
learn how to properly hold the arc and not burn the product;
do not rely on luck in working with the device, but carefully read the instructions containing all the necessary amount of information;
special attention must be paid to safety precautions;
it is better not to operate the unit in dusty rooms, as generators "do not like" dirt.

When working with an inverter welding machine, it is important to take into account the specifics of its connection to the generator. In case of incorrect station selection, the inverter may be damaged.

In this case, even taking into account only power, as noted earlier, does not resolve the issue of compatibility.

How to do it yourself?

You can make a generator for welding yourself. For these purposes, it is better to use a separate room, for example, a workshop or garage.

The first element to start with is the frame. In its quality, a corner measuring forty by forty millimeters is perfect. After the desired length is cut with the help of a grinder, holes are drilled in it for the motor and generator. These elements are bolted to the frame.

It is worth noting that in this situation it is possible to assemble a welding machine from a car generator.

This is followed by the installation of the wheels to the base of the frame to allow for easy movement. The wheels can be fastened by welding or bolted.

Features of welding generators.

The principle of operation of the device is based on the transfer of torque from the motor to the generator, as a result of which it forms a current.

This scheme is at the heart of the operation of each device.

The unit is capable of working without a gas generator. The mains voltage can also be supplied to the generator, which is subsequently converted into the required current for welding.

As you can see, making a welding generator yourself is not difficult. It is also possible to make a welding machine from a laboratory autotransformer.

Model overview

It is appropriate to start acquaintance with welding power plants with Miller Bobcat 250 DIESEL. The manufacturer positions its development as an excellent means of supplying current in the field. This model is also useful for working with metal structures, including on an industrial scale. It can be used to guide:

fusible electrode welding;
semi-automatic welding with flux-cored wire or in an inert gas atmosphere;
air plasma cutting;
argon arc welding with direct current.

Designers promise excellent seams on a wide variety of metals. The device is equipped with a maintenance indicator. There is a meter showing the diesel engine hours and the recommended interval before changing the lubricating oil. If the cooling system overheats, the generator will shut down automatically. Therefore, even a very intensive operation will not affect its working life.

The technical parameters are as follows:

output voltage - from 208 to 460 V;
welding voltage - 17-28 V;
weight - 227 kg;
total generator power - 9.5 kW;
noise volume - no more than 75.5 dB;
network frequency - 50 or 60 Hz;
inverter three-phase design.

You can take a closer look at another product of the same brand - Miller Big Blue 450 Duo CST Tweco. It is a two-post generator optimized for:

shipbuilding;
other branches of heavy engineering;
Maintenance;
overhaul.

The device is designed for a voltage of 120 or 240 V. No-load voltage is 77 V. The mass of the generator is 483 kg. It generates up to 10 kW of current. The noise volume under normal conditions does not exceed 72.2 dB.

But the power of the generated current reaches 21.6 kW. The internal volume of the combustion chamber is 1498 cubic meters. cm.

Other parameters are as follows:

weight - 570 kg;
voltage - 230 V;
diameter of the welding wire (electrodes) - up to 6 mm;
total power - 29.3 liters. with.;
welding current range - from 300 to 400 A.

The next machine is the SDMO Weldarc 300TDE XL C. The maintenance and transport of this welding generator is easy. The device is suitable for long-term uninterrupted power supply. The manufacturer claims that the model works reliably for a long time. The quality of the output current is at the proper level, moreover, the designers took care of the safety of the operators.

Basic properties:

total power - 6.4 kW;
generator weight - 175 kg;
diameter of electrodes (wire) - from 1.6 to 5 mm;
welding current - from 40 to 300 A;
electrical protection level - IP23.

There are also a number of other attractive devices. For example, diesel generator LEEGA LDW180AR. It is also protected according to the IP23 standard. You can start generating current with a manual starter. The current range is from 50 to 180 A, while only direct current is generated.

The manufacturer guarantees that it will be possible to supply the instrument with current with the help of the generator. The parameters of such a power supply are 230 V and 50 Hz, as in a conventional city power grid. The tank can be filled with 12.5 liters of diesel fuel. On a full charge, current generation can continue for up to 8 hours in a row. Model:

certified for compliance with Russian GOST;
tested in the framework of the European CE regulation;
received the TUV certificate (key industry regulation in Germany).

Power supply selection

How to choose an autonomous power source for a welding inverter machine? When powering an inverter welding machine from an industrial network, there is no need to worry about the stability of the power source.But in the field, at construction sites, it is not always possible to connect to power grids. To do this, you need to choose autonomous power supplies. The most common and demanded type is a small-sized gasoline generator.

But this raises a number of questions:

what power does the welding inverter consume ?;
will the gas generator pull this device or not?;
What is the power output of the generator for the welding machine to work reliably?

The topic of in what cases, to which generator to connect, is widely disclosed by the forum of experts on the Internet. It tells you which welding equipment is best to use on construction sites.

Using an inverter with a gas generator

Power calculation

First of all, you need to familiarize yourself with the parameters of the welding machine, they are in the passport for the product, you can from the Internet. For example, a welding machine delivers a maximum current of 160A, it is necessary to calculate what maximum power the welding machine can consume. The formula is used:

P sv = Is x Ud efficiency, where

R sv - maximum power consumed by welding machines;
Is - maximum current of the welding machine 160A;
Ud - arc voltage during welding 25V;
Efficiency is the efficiency of the inverter device, most likely it will be 0.85.

P sv = (160 x 25) 0.85 = 4.7 kW or 4700 W.

During the welding process, the maximum power mode is never used constantly. Welders work within an adjustment range from average to maximum current, depending on what material they are dealing with.

We need to calculate the average power consumption of the welding machine for the period of welding. The passport indicates such a parameter as PV, this is a time correction in percentage for the use of maximum power during operation. Usually the duty cycle is 40%, in order to calculate the average power, the maximum must be multiplied by the duty cycle 100, you get 4700 x 0.4 = 1.88 kW.

In some passports for inverter devices and generators, power is indicated not in kW (kilowatts), but in kVA (kilovolt-ampere). This difference must be taken into account. Both units measure the consumed power, kW - shows the consumption of active power, kVA - full.

Ideally, when using heating devices as a load, all the power is active, the current is converted into heat kVA = kW. But with a different load, with inverter machines, electric motors and other consumers, only part of the power will be active, which will go to spin up the rotor of the electric motor or warm up the electrode of the welding machine. A reactive component appears, which is spent on heating the wire, semiconductor elements of electrical circuits. As a result, the total consumed power will be more active.

To assess the ratio of active and reactive power, taking into account the appearance of linear and nonlinear noise in the network with various loads, the power factor (KM) cos-ϕ was introduced. Its optimal value is 1, when the load is a heating element, for KM inverter devices is indicated in the passports of approximately 0.8. To convert kVA to kW, multiply kVA by cos-ϕ (KM), to convert kW to kVA, you need kWsos-ϕ (KM). In this case:

4700 kW 0.8 = 5875 kVA;
5875 kVA x 0.8 = 4700 kW.

Another method is easier for the average consumer to remember:

4700 kW + 20% = 5875 kVA;
5875 kVA - 20% = 4700 kW.

Knowing the total power consumption of the welding machine, you can choose a generator.