How is the welding machine connected?
In order for welding work to proceed without unnecessary problems, you need to figure out how to connect the welding machine. Before connecting the unit for welding, it must be placed in a suitable location.
It is very important that nothing obstructs the air flow to the openings on the equipment body. Cooling is often intentionally increased. To do this, when connecting the welding machine, install a fan behind it.
It is very important to ensure that the unit does not come into contact with dust, as well as wet and aggressive vapors.
Homemade welding machine for DC welding.
Basic recommendations and safety precautions
Before you are going to connect the welding machine, be sure to make sure that the frequency and voltage indicated on the equipment case match that of the network. Connecting such equipment requires making the correct connections. For this, the following wires are used: a phase or 2 phases in combination with a neutral and a grounding wire, which is usually green or yellow.
Electrode position during welding.
If the welding machine model you have chosen allows you to set the voltage yourself, you should fix the switch in a position that would correspond to the voltage in your network. The position is fixed using a locking screw.
A plug is used to connect the welding machine. It is very important that it meets established thermal throughput standards. This plug must have a grounding lug. It is to this that the corresponding cable will be connected. This plug cannot be plugged into a regular household outlet. A fused socket is suitable for connection. An auto switch is also suitable.
You will need to connect the return ground cable to the appropriate terminal. You need to connect at the shortest possible distance from the future seam. A specially designed clamp is used to attach the cable holder to the protruding fragment of the electrode.
Before connecting the welding unit directly to the network, be sure to check how securely the plugs are secured.
Due to poor contact, the device will not work at full capacity and will quickly fail.
Figure 1. Connection diagram of the welding machine: 1-welding station; 2—three-core hose cable; 3 - transformer; 4-regulator; 5-grounding clamps of the unit body; 6 - single-core hose cable; 7-electric holder; 8 - ground wires.
There are quite a lot of schemes according to which the welding unit is connected. The most common connection diagram is shown in Fig. 1.
- Position 1 is a welding station;
- number 2 indicates a three-core hose cable;
- 3 - transformer;
- 4th position - regulator;
- number 5 - grounding clamps of the unit body;
- 6 - single-core hose cable;
- 7th position - electric holder;
- number 8 - ground wires.
Remember and follow all these rules when connecting the welding machine to avoid injuries and other unpleasant consequences. Failure to comply with the safety system of the welding machine may result in fire or electric shock.
If any of the power cables break, they must be replaced immediately. It is best to entrust this work to professionals.
Any repair and maintenance work can be performed only after the welding machine is disconnected from the network.
When connecting the welding machine, be sure to check the quality of the permanently laid and flexible wires. Check their grounding, continuity and insulation to ensure compliance with established standards. Don't skimp too much on grounding.
It is best to use flexible copper wire for it. If twists, cracks or other defects are detected, the wire must be replaced. The use of damaged wires leads to overheating and may cause damage to the welding machine. An important fact is the need to unwind the wires.
If this requirement is neglected, inductance will occur and resistance will decrease.
The voltage for welding machines is not standardized, so pay attention to the characteristics of the particular model you will be working with. When assembling such equipment, it is given a certain voltage level. The resistance value is not taken into account.
Step-by-step instructions for connecting a welding machine
Figure 2. Sequence diagram for connecting the welding machine.
After you have checked the integrity of the unit and all related components, and also established the voltage compliance, you can proceed directly to connecting your welding machine. For this you will need:
- the unit itself;
- extension;
- adapter for extension cord.
When connecting the device, you can refer to the diagram in Fig. 2.
The connection is made in a certain sequence, namely:
- First, a plug is prepared with the appropriate thermal throughput parameters.
- Select a socket with a circuit breaker or fuse.
- The return cable is connected to the terminal.
- The holder cable is connected to the electrode fragment using a clamp.
After you have done all this, the welding machine can be connected to the network. Most models have fairly short wires, so connecting them often requires the use of an extension cord. The extension cord must have a wire of sufficient cross-section. The reliability and safety of operation depends on the number of intermediate connections. The fewer there are, the better.
Connection features depending on the type of device
Figure 3. A transformer-type welding machine can operate in a wide range of welding current. It is recommended to connect it to the shield.
The procedure for connecting the welding machine largely depends on the features of its device. So, if a two-phase model is used, the wires will be connected in an individual sequence.
The first wire will need to be connected to the phase, the second to the neutral output, and the third wire to be connected to the protection. If you work with a three-phase welding machine, then you don’t have to follow a special sequence.
The main thing is that the first 2 wires are connected to any phases, and the third wire is connected to the protection.
It is very important to know the basic features of connecting a transformer-type device. A typical representative is shown in Fig. 3. If such equipment is used, the connection is made in accordance with a number of special rules.
Transformers can operate over a wide range of welding currents. When some of them are plugged into an outlet, a fairly powerful surge of current is generated, which can burn the outlet and turn off the circuit breaker. Therefore, it is recommended to connect such a welding machine to the shield.
A detailed connection diagram for the welding transformer is shown in Fig. 4.
Be sure to follow these rules while working. If they are not followed, you risk injury that could easily be avoided. As a result of incorrect connection of the welding machine, you may receive an electric shock, a decrease in the quality of welding, fire, etc.
Possible problems after connection
Figure 4. Connection diagram for welding transformer.
After connecting the welding machine, various problems may arise, for which you need to be prepared and know how to get rid of them. If there is strong heating of the windings and humming, then the reason lies in a turn short circuit in the primary windings. In this case, you will have to completely or partially rewind the windings.
Welding transformers may produce too much current due to a short circuit in the regulator winding or in the secondary winding. To eliminate the malfunction, you need to eliminate the short circuit in the windings or rewind.
If, when exposed to the regulator, the welding current does not decrease, then the reason, as a rule, is a short circuit between the terminals of the regulator.
While working with the device, you may hear an uncharacteristic hum. It usually appears due to weakening of the spring tension or due to a broken wire.
The cause of excessively hot contacts in connections is usually faulty electrical contact. You can get rid of this malfunction by rebuilding overheating connections. The contact surfaces are cleaned and fit tightly. The clamps are tightened until they fail. Good luck!
Source: https://moyakovka.ru/instrumenty/podklyuchenie-svarochnogo-apparata.html
How to properly connect an inverter welding machine
Reading time: ≈5 minutes
So, you have purchased your first inverter welding machine. You will probably find an instruction manual included with it. Having carefully studied it, you will find that only a few general phrases are said about the correct inclusion. Is it really that simple? Plug the plug into the outlet and that's it? Alas, no.
An inverter-type welding machine is a complex device with its own nuances and features. By thoughtlessly plugging it into a household outlet, you risk losing the device itself or the wiring in the house. So how to connect a welding inverter correctly?
In this article we will briefly describe how to connect a welding machine to a 220 Volt home network and what should be taken into account.
Pre-check
Before you learn how to properly wire a welder, you need to make sure that the wiring in your home can handle the welding job.
Inspect the sockets, how old are they? If the outlets have not been replaced for more than 25 years, most likely all the wiring in the house is also old. This is not critical if it can withstand high current values. But often old wiring brings nothing but problems.
You are unlikely to be able to use modern welding wires with the machine if the power supply in the house is far from ideal.
You don't need to be an electrician to understand what will happen if you connect a powerful modern welder to old sockets. At best, you will be left without electricity. In the worst case, all your neighbors will be left without electricity, and your electrical appliances will simply fail.
In a word, check first whether your wiring can withstand the load. If you find that it can't, don't despair. This problem can be solved. We'll talk about this later. In the meantime, below is a diagram of connecting the welding machine.
Application of a current generator
So, you checked your wiring and it turned out that connecting a 220V welding machine is simply impossible. What to do in this situation? You can use a third-party current generator.
https://www.youtube.com/watch?v=8dR1RfoteHc
And at this moment, many immediately begin to remember that they keep an old gasoline generator in their dacha, which more than once saved them from sudden power outages. On the surface, the use of such generators seems like a pretty good idea, but in practice everything is different. Often, all gasoline generators are low-power and are not capable of providing a voltage of more than 5 kW for a long time.
As you understand, connecting a welding inverter to a low-power gas generator is simply pointless. To find out how much power you need, simply multiply the amperage you'll be cooking with by the voltage.
Let's take the most popular situation: you are welding with a 3 mm electrode with a current of 120 Amps and a voltage of about 40V. We multiply 120 by 40, we get 4.8 kW. This is the minimum power that a gas generator must provide. But in the calculations we did not take into account the efficiency of the welding machine, which is less than 100%. To ensure uninterrupted operation of the inverter you need at least 6 kW.
In general, a gas generator is a choice for those who no longer have any opportunity to obtain an additional power source. Ideally, before purchasing an inverter, you should check all the wiring and, if it is unsuitable, buy a welder with a built-in generator. Yes, these models are expensive and very bulky. But this is the most convenient solution to the problem.
If this solution is inconvenient for you, then you can buy a special current stabilizer for the welding machine. It connects directly to the welding inverter. This solution is suitable for a more or less stable power grid.
Use of extension cords
The topic of extension cords does not relate to connecting a welding machine, but these two issues are related. The fact is that if you select the wrong extension cables, the voltage may drop and the efficiency of the welding machine may decrease.
Why are extension cords needed? After all, the kit already contains quite long wires, usually up to 2.5 meters. At first this may be enough, but over time you will want more freedom for your actions. Especially if the device is heavy, and you need to move around the entire summer cottage or cook at height.
Therefore, we decided at the same time to tell you about connecting extension cables. First of all, remember that they cannot be used thoughtlessly. You need to accurately calculate what cross-section the extension wire should have. The maximum power that the wire can withstand will depend on this.
Let's give a simple example, using the same numbers from the previous example. Let's say we need a welding current of 120A. Wire cross-section 2.5 sq. mm. gives us 16A. Accordingly, for welding with a current of 120A, we need a wire with a cross-section of at least 12 sq. mm. We recommend choosing extension wires with a spare cross-section. Also remember to untangle them before welding so that it cools better. And don't forget about grounding. This is the simplest safety rule.
Also, do not buy several short extension cords and connect them together. It’s better to decide in advance on the required length and buy one wire. This way you will reduce the likelihood of a decrease in the efficiency of the welding machine. In addition, the contact connections of the extension cord will last you much longer.
Source: https://MyTooling.ru/instrumenty/kak-pravilno-podkljuchit-invertornyj-svarochnyj
What you need to know to assemble a welding machine with your own hands
Anyone familiar with the rules of electrical installation can easily make a simple welding machine on their own. But before getting down to business, it is necessary to calculate all the components of the device. The efficiency of the device when operating from a regular household single-phase network will depend on this.
Design and principle of operation of the simplest welding machines
To obtain a stable welding arc, which will allow you to weld metal of different thicknesses, currents in the range of 70 - 150 A are required. If you use devices designed for a voltage of 220 V, then they must consume high power, in the range of 15 - 30 kW. Therefore, such installations will be cumbersome, and it will not be possible to work with them normally. But at home it will simply be impossible to connect them; standard networks are not designed for such a load.
Therefore, the main task in the design and assembly of welding machines is to provide the required current while reducing power consumption. This is only possible when performing welding work with reduced voltage on the electrodes.
The simplest welding machine has the following design:
- A step-down transformer that reduces the voltage to the limits of 55 - 70 V and at the same time increases the current strength to the required parameters. Thanks to this, it is possible to reduce energy consumption to reasonable limits.
- Current is supplied from the transformer to the electrode and the workpiece using special welding cables. They are distinguished by a larger cross-section and reinforced insulation, allowing them to work with high currents.
- For welding, you will need electrodes installed in the holder. Thanks to the coating used, they simplify the ignition and maintenance of the electric arc, which becomes the source of thermal energy necessary for melting the metal.
Welding transformer
There are no complex devices in the design of such welding machines. But during design, it is necessary to calculate the basic parameters, otherwise connecting inappropriate equipment to the network will lead to its failure, short circuits on the line, or it will simply be impossible for them to cook.
Types of welding machines
There are several main types:
Welding transformer. A step-down transformer is used for the converter.
Welding transformer
Welding inverter. An inverter power supply with PWM serves as a converter here.
Welding rectifier. This is the same as a welding transformer, only it has a diode or thyristor rectifier in the secondary circuit.
Welding rectifier
Semi-automatic Welding is carried out in an inert environment; a gas cylinder is used for this.
Also read: How to make a phase indicator with your own hands
Simplified welder calculation diagram
In practice, calculations are made based on the type and diameter of the electrodes used. Yes, there are more complex and accurate calculation formulas, but they are rarely used by amateurs. To obtain a stable and productive arc, it is necessary to obtain a current with the following indicators:
- For electrodes with a diameter of 2 mm, 30 - 80 A is sufficient.
- When the diameter increases to 3 mm, the current should increase to 70 - 130 A.
- For 4 mm electrodes, the value is set to 110 - 170 A.
- 5-mm electrodes are cooked at a current of 150 - 200 A.
The difference in current values is due to working with metals of different thicknesses and physical properties.
When making a welding machine yourself, you most often have to be content with a magnetic core from other devices, which is available. Therefore, the simplest calculation will be performed based on these two known characteristics - the cross-section of the magnetic circuit and the required current strength on the secondary winding.
Please note that it is preferable to use rod-type cores to assemble the transformer. Compared to armored ones, they provide a higher current density in the windings and have increased efficiency.
Types of magnetic cores
In addition, the location of the windings on the arms of the core is also important. If the primary and secondary windings are separated into different rods, this will lead to increased magnetic dissipation due to the increased air gap. Therefore, it is considered preferable to place a part of both windings on both one and the other rod.
In this case, to determine the required number of turns of the primary winding, use the following formula:
N1 = 7440 × U1/(Sout × I2)
Where
N1 - estimated number of turns;
U1 - mains voltage (200-240V);
Source: https://OFaze.ru/svoimi-rukami/svarochnyj-apparat
How to connect the welding machine to the network?
Reading time: ≈5 minutes
So, you have purchased your first inverter welding machine. You will probably find an instruction manual included with it. Having carefully studied it, you will find that only a few general phrases are said about the correct inclusion. Is it really that simple? Plug the plug into the outlet and that's it? Alas, no.
An inverter-type welding machine is a complex device with its own nuances and features. By thoughtlessly plugging it into a household outlet, you risk losing the device itself or the wiring in the house. So how to connect a welding inverter correctly?
In this article we will briefly describe how to connect a welding machine to a 220 Volt home network and what should be taken into account.
Instead of a conclusion
Connecting the inverter to the grid is a simple process. You just need to learn everything once and then follow the rules. In addition, these rules also apply when you need to connect a 380V welding machine. If you have a transformer or semi-automatic in your arsenal, the algorithm of actions will not change either. We wish you good luck in your work!
Source: https://svarkaed.ru/oborudovanie-dlya-svarki/poleznaya-informatsiya-ob-oborudovanii/kak-podklyuchat-svarochnyj-apparat-k-seti.html
How to connect welding cables to each other, connect to an inverter, clamp in a holder, extend, etc.
Quite often, welders have problems connecting cables . This question may arise for several reasons: the wire that comes with the welding machine is not long enough, or the cord was broken or damaged during work. Therefore, it is important for performers to know how to properly connect welding cables and extend them.
How to connect
It should be remembered that the safety of the performer and the quality of the work performed depend on the reliability of the contact connections of the conductors. The connections are subject to high technical requirements . But first of all, they must be resistant to shocks, tears and other mechanical influences. Therefore, it is very important to know how to connect two welding cables to each other.
The following are the most popular methods of connecting welding cables, each of which has its own advantages and disadvantages.
Let's look at the connection of welding cables in more detail.
1. The simplest way is to use additional accessories - welding connectors for connecting cables . They make work simple, fast and convenient. In addition, the use of connectors has a positive effect on equipment mobility.
There is a wide variety of these accessories on the market, differing in technical characteristics. Connection of welding cables: “male-female” - is a classification based on differences in the design of the connectors. You can find out how to choose the right detachable connections for welding cables and what you should pay attention to here.
2. The “twist” connection is the first and oldest method, characterized by fairly simple execution, quality and reliability.
Main disadvantages : this method is prohibited by a group of regulatory documents PUE (“Rules for the construction of electrical installations”); is an intermediate step before welding or soldering.
The prohibition of the PUE method does not prevent homemade workers from successfully using it, as shown in the video below.
“Twisting” can be done in several ways, which are presented in the pictures below. Regardless of the chosen method, the insulation of the cores should be removed by at least 3-4 cm. Then the sections of the cores must be treated with acetone or white spirit, cleaned with sandpaper and you can begin twisting.
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There are also ways to connect welding cables if you have a certain set of equipment and additional accessories.
3. Soldering is a method of connecting cables by covering the heated ends of the wires with molten solder, which hardens and provides strength and high electrical conductivity of the connection. This method is used for small cross-section conductors.
Advantages: does not require special skills and specialized equipment compared to welding.
However, it is worth highlighting the disadvantages: a large number of preparatory operations, therefore, high labor intensity.
Before soldering, the conductors are cleaned of insulation and oxide film, then they are tinned, twisted and pressed with pliers. To avoid oxidation of the cleaned surface, fluxes should be applied to the treated areas.
Soldering of small copper wires is carried out using solder tubes filled with rosin or a solution of rosin and alcohol. These solutions are applied to the joint before soldering.
Then you can begin the soldering process: the joint is heated with a soldering iron or torch. Rosin or flux begins to boil, take a little solder onto the soldering iron tip and add it to the soldering zone by pressing the tip against the conductors. The solder spreads and fills the gaps between the wires, thereby creating a connection. If a torch is used, the solder is added to the torch.
After the soldering process is completed and the workplace has cooled, the flux residues must be washed off, the joint dried, coated with a special varnish, and insulated with tape or heat-shrinkable tubing.
4. Crimping is the process of connecting wires using copper or aluminum sleeves. It is necessary to select a sleeve depending on the size of the “twist” and the cable material (copper or aluminum).
The wires must be cleaned to a metallic shine, bundled/twisted, and then a sleeve is put on them and clamped with special pliers. In this case, the walls of the sleeve are pressed into the conductor conductors and a reliable electrical contact is formed.
Advantages : high reliability; no high demands are placed on the performer regarding his qualifications; independence from the availability of electricity.
Disadvantages: rigid sleeve leads to wire rupture near the sleeve; it is necessary to have a supply of sleeves of various sizes; if the connection is larger than the diameter of the cord, the cable will touch surrounding objects.
How to connect to an inverter
The question of how to properly connect cables to a welding inverter arises when deciding on polarity when welding with direct current: forward or reverse.
The “plus” sign is connected to the electrode holder, the “minus” sign is connected to ground - welding is performed with reverse polarity . In this case, the current moves from the electrode to the workpiece, the metal heats up more than the electrode.
The “minus” sign is connected to the electrode, the “plus” sign is connected to ground, therefore, the polarity is straight. The current flows from the workpiece to the electrode, creating stronger heating of the electrode.
Which polarity should be used depends on several factors: the type of metal; workpiece thickness; electrode type.
More detailed information on how to connect cables to a welding inverter depending on the selected polarity is presented in the corresponding article.
You should also pay special attention to the basic rules for connecting welding cables to inverter-type equipment. These nuances will guarantee a safe and comfortable work process.
Reading this information will help you learn how to connect welding cables to a specific type of equipment.
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How to hold it in a holder
The method of fixing the welding cable depends on the type of electrode holder : homemade or purchased (produced by companies of the corresponding profile).
Types of homemade holders and methods of assembling them, their main advantages and disadvantages are discussed in the article “Electrode holder for a welding machine.” This article also presents a method for correctly and securely connecting the cable to the electrode holder.
You should also pay attention to the recommendations of the master , who will help you make a professional, competent holder yourself. For clarity, a video of the assembly of the holder is presented.
To understand how to connect welding cables to the purchased holder , we recommend that you watch the video below. The performer can clearly see that the cable, together with a metal gasket (plate), is inserted into the corresponding hole and securely fixed with a key by tightening the screws.
How to extend the cable on an inverter
Typically, the inverter is equipped with a wire no more than two meters long. Working with such a cable is quite problematic and inconvenient. Therefore, performers often have a question: how to extend the cable on a welding machine ?
Previously, we considered that connecting welding cables should be done in several ways, each of which is used depending on the skills of the performer, the presence or absence of specialized equipment and additional accessories.
Advice! In most cases, the owner of the welder connects the welding cables for the holder and the ground into one longer wire and uses it to connect to the ground . And for the electrode holder, the welder buys a part of the cable of the required length .
It is important to know how to extend a welding cable. The connection of welding cables during extension can be performed using the following methods: welding; soldering; crimping.
It is also worth noting the opinion of some professionals who are against lengthening the conductors . Cables that are too long may adversely affect the performance of the device. In addition, the longer the wire, the greater the current loss, which can negatively affect the quality of welding.
How to choose a welding cable
Equipment of any type will serve its owner for a long time if the wire is selected correctly. When choosing a conductor, you need to pay attention to the following points :
- the cable must meet the technical requirements for it: resistance to impacts, breaks, bends, aggressive chemical environments, temperature changes, ultraviolet radiation, mold formations;
- The cord must withstand the maximum current that the welder’s unit produces.
More detailed information is presented in the articles on KG, KOG cables, as well as in the publication on conductors for the inverter.
How to find out the cross section
The main technical characteristics of conductors: cross-section, diameter and other important properties are indicated in catalogs or corresponding descriptions. However, if the contractor does not have the opportunity to familiarize himself with this data, and the question of how to determine the cross-section of the welding cable needs to be answered, then you should remember some recommendations.
There are several ways to determine the cross-section of a conductor. They all boil down to the fact that first you need to calculate the diameter of the core. This can be done using a micrometer or caliper. However, the simplest method, which does not require special accessories, is to use the following method.
The contractor will need to remove the insulation from the conductive core. Then you need to wind the core around a cylindrical object (screwdriver) and use a ruler to measure the total length of the turns, the number of which for accurate calculations should exceed 10. In conclusion: the total length in mm. must be divided by the number of turns. The resulting value will be the diameter of the wire, from which the cross-sectional value can be found.
The contractor can find complete information about the cross-sections of cables of various brands in articles devoted to this topic:
- “Welding cable KG”;
- “Welding cable KOG.”
Source: https://WeldElec.com/svarka/post/osnastka/kabel/soedinenie-podklyuchenie-udlinenie/
How to properly connect a welding inverter plus minus - Metalworker's Handbook
When welding a structure using direct current, it is important to know that the quality of the seam will depend largely on the settings of the machine. An important nuance is that in addition to the current regulator, it is necessary to select the correct polarity. There can be only two types - direct and reverse polarity when welding with an inverter.
What does straight polarity mean?
In order to achieve a high-quality seam when welding various steels, it is important to know which polarity is suitable for the material that needs to be processed. The general essence of welding with an inverter is that the machine must have “+” and “-“ sockets. Depending on which socket the ground will be connected to and which the electrode will be connected to, the polarity will depend.
Direct polarity is connected in this way: a ground is added to the positive socket, and an electrode is added to the negative socket. It is important to know here that the type and polarity of the current will be determined by the existence of the anode and cathode spots. During straight polarity welding, an anodic spot, which is hotter, will form on the workpiece side.
What does reverse polarity mean?
With reverse polarity, it is logical that the connections of the ground and the electrode are swapped. That is, an electrode is connected to the positive socket, and ground is connected to the negative socket. Here you need to understand that when connecting the sockets in this way, an anode spot will also form, but it will appear not on the side of the workpiece, but on the opposite side from it, that is, on the electrode.
Important note! Connecting the polarity manually is carried out only when welding with an inverter, that is, in the presence of direct current. When carrying out the same process, but on alternating current, the polarity is changed up to hundreds of times per second independently. Therefore, the connection method does not matter.
As you can see, the difference between direct and reverse polarity when welding with an inverter is that the anode spot will form in different places.
Polarity selection criterion
When changing the connection, the specialist changes the location of the heat concentration, transferring it either to the workpiece or to the electrode itself. It is important to know here that the socket with a plus is responsible for heating, which means that with a direct connection, the maximum temperature will be observed at the welding seam. When connected in reverse, the maximum temperature is spent on heating the consumable element.
Knowing this feature, you can independently choose the connection diagram based on such a parameter as the thickness of the material. The choice between forward and reverse polarity when welding will greatly depend on the thickness of the metal product. If this parameter has a medium or high value, then it is best to resort to straight polarity.
This is explained by the fact that strong heating of the workpiece will provide a deeper seam, which, in turn, will improve the quality of the weld. Straight polarity is also used when cutting pieces of metal.
And, on the contrary, when welding thinner metal workpieces, it is recommended to use a reverse connection, since the material will not overheat too much, but the electrode will melt much faster.
Metal type
Forward and reverse polarity when welding will also depend on the type of metal product that needs to be processed. It is important to understand that the ability to independently change the type of connection affects the efficiency of working with various types of workpieces. An example is welding stainless steel or cast iron.
When working with such materials, it is best to use reverse polarity, which will avoid severe overheating of the raw material, which will eliminate the need to create a refractory welded joint. But, for example, when working with a type of metal such as aluminum, it is best to use straight polarity when welding. Since with low heating it will be very, very difficult to break through the oxides of this raw material.
Most often, each material has a recommendation that states what type of polarity is best to process this workpiece.
Types of electrode and wire
Another very important detail that must be taken into account when welding with a direct or reverse polarity inverter is the type of electrode, which, like metal, has its own characteristics at different temperature conditions. Most often, the parameters are related to the type of flux used in the base of the consumable. Let's say we have a carbon-type electrode.
It is impossible to use a reverse connection to work with such an element, since too much heating of a consumable of this type will overheat the flux and the product will become completely unusable. You can only use DC welding with straight polarity.
Here, as in the case of metal blanks, in order not to make a mistake, it is best to study the markings and manufacturer’s recommendations for working with each type of consumable separately.
Properties of straight polarity
It is quite obvious that there are advantages to welding with direct and reverse polarity. If we talk about the first type of connection, we can highlight the following points:
- the resulting weld will be quite deep, but at the same time quite narrow;
- used when welding most metal workpieces whose thickness is higher than 3 mm;
- Welding, for example, non-ferrous steel is possible only with a tungsten electrode, as well as with a direct connection to the inverter;
- straight polarity when welding metals also has a more stable arc, which, in turn, ensures a higher quality weld;
- when using a direct connection, it is strictly prohibited to use electrodes that are suitable for welding with alternating current;
- straight polarity has also proven itself in cutting metal workpieces.
Reverse polarity properties
Just as direct polarity during welding has its strengths and weaknesses, reverse connection can also be characterized by certain properties:
- If you use DC welding, but make a reverse connection, the resulting seam will not be too deep, but very wide.
- The best weld quality is achieved only when working with thin metals; if reverse polarity is used to weld thick materials, the weld quality will be too unsatisfactory.
- When welding on a reverse connection, it is strictly forbidden to use electrodes that cannot be overheated.
- If the current strength decreases significantly, the quality of the seam will also deteriorate significantly due to the fact that the arc will begin to “jump”.
- Since reverse polarity is most often used for welding high-alloy steels, it is necessary to be guided not only by the rules of welding with an inverter, but also take into account the requirements of the metal for the duration of the working cycle, as well as for the cooling process of the metal.
After a person has studied in detail the features of welding with direct polarity, as well as with reverse polarity, it becomes quite simple to answer the question of why change it. To briefly summarize, we can say the following:
The use of direct polarity is justified in cases of large metal thickness. Also, this type of connection is justified if non-ferrous metal is welded: brass, copper, aluminum.
It is most important to pay attention to working with aluminum, since its oxide film has a huge melting temperature, which greatly exceeds the melting point of the raw material itself.
In other words, we can say that straight polarity welding is the rough processing and joining of the structure.
Source: https://ssk2121.com/kak-pravilno-podklyuchit-svarochnyy-invertor-plyus-minus/
How to connect welding leads to a welding inverter
The inverter welding machine has gained wide popularity among home craftsmen and small repair shops. To obtain a strong and durable seam, a powerful and serviceable machine is not enough. High-quality wires for the welding inverter of suitable cross-section, type and length are also required.
Device
Of the available metals, copper serves as the best conductor . Combined with its flexibility, this makes it an ideal material for making the base of welding wire - conductors.
https://www.youtube.com/watch?v=edwILvaxWls
The structure consists of the following main parts:
- copper core, twisted from a large number of copper wires with a diameter of up to 0.5 mm;
- separating layer - a thin shell that prevents the core and the insulation layer from sticking together, can be supplemented with talc or other powder;
- an insulating coating consisting of rubber, rubber or other polymer.
The ends are provided with contacts to connect to the inverter and holder. They are crimped and soldered to ensure the best contact.
Characteristics
The most important characteristic required for a wire is its cross-section . It determines the maximum current passing through the cable. No less important is the resistance, which causes electricity losses on the way from the device to the electrode. Mechanical parameters are of great importance:
- strength: ability to withstand loads;
- elasticity: the ability to return to its original shape after deformation
- temperature resistance: the ability to maintain working properties when temperature changes;
- ability to withstand sunlight and humidity;
- resistance to fungus and mold;
Kinds
With household and semi-professional class inverters, the most common in home workshops, single-core wires of the KG brand are mainly used.
Depending on their purpose and characteristics, they are:
- KG-HL , insulation is made of frost-resistant rubber, they work in the cold;
- KG-T , insulation impregnated with substances that prevent the growth of fungus and mold, used in humid climates
- KOG , highly flexible wires, for welding in hard-to-reach places, for example, in shipbuilding.
According to the number of cores they are divided into:
Single-core
Most of the inverter wires are single-core.
One wire connects the device terminals to the electrode holder, the other to the ground clamp on the workpiece.
Twin-core
Used for high frequency welding and alternating current operation . Two cores have their own insulation; the outside is covered with another insulating layer. Alloys of copper and other non-ferrous metals are used as materials.
Three-core
Such wires are used to connect automatic welding systems connecting pipelines and large containers.
Each core also has its own insulation.
Section selection
The correctly selected welding cable cross-section for the inverter will allow you to work safely and with the expected performance. If the wire cross-section is insufficient, the resistance of the wire will cause loss of current due to its heating; as a result, the machine will not be able to develop the required welding current and the quality of the seam will deteriorate sharply. In this case, the indicator on the inverter will blink , indicating an overload.
In order to connect low-power portable inverters operating from a 220V network, light and flexible wires with a cross-section of up to 16 mm2 are used.
For more productive devices, a cross-section of up to 50 mm2 will be required.
Correct connection
Proper connection ensures the welder productive and safe work.
Connecting wires to a welding machine requires compliance with a number of rules:
- there must be a terminal at the end, crimped or soldered;
- The wire cross-section must correspond to the maximum operating current of the device plus a margin of 20%
- You should carefully monitor the polarity of the connection and observe it;
- The cable must lie freely in the work area, without tension or loops.
How to connect a welding machine if there is not enough wire to the welding zone? You can increase its length.
Is it possible to extend the welding cable on the inverter?
When increasing the length, you need to understand that the longer the cable for connecting the welding inverter, the greater the losses and the lower the resulting current strength.
If it is necessary to weld at a great distance from the machine, wires of a larger cross-section should be connected to compensate for losses.
When splicing 380V cables equipped with terminals with a hole into a single circuit, they should be cleaned and securely connected with a bolt and nut, not forgetting to install large diameter washers. The connection point must be carefully insulated, taking into account the fact that the wire will be repeatedly pulled through metal and concrete.
How to connect an inverter if there is no crimped terminal on the cable? Wires are spliced by repeatedly interweaving the wires that make up the core . Then the connection point should be soldered and crimped.
There are also special extension cables that have crimped and insulated connectors. Their type must match the connector of your device.
Manufacturers do not specify any restrictions on cable length. In each case, the welder himself decides what is better - to lengthen or drag the inverter and gas generator more often .
Marking of welding cables
The welding wire marking consists of several groups of letters and numbers. From it you can understand which model is in front of us.
First there are several letters indicating the type of cable.
After the type, a dash may indicate the climate class of the wire:
Next comes a number indicating the number of cores - 1, 2 or more. The designation is completed by the cable cross-section in mm2.
Safety requirements
When welding work, the following requirements must be observed:
- Do not work with wires with damaged insulation or insufficient cross-section;
- the wire in the working area should be placed freely, without clinging to the welder’s hands or feet;
- there must be enough light in the working area for the welder to move confidently;
- When connecting to the device, polarity must be observed.
Correctly selected wires for a welding inverter are the key to safe and productive work . You need to pay attention to the cross-section, length and climate class of the cable. Cable extension can be carried out in strict accordance with the requirements of the regulations.
Source: https://svarka.guru/oborudovanie/rashodniki-i-kompletuyushie/provoda-k-invertoru.html
How to connect a welding machine - Welding Pro
Reading time: ≈5 minutes
So, you have purchased your first inverter welding machine. You will probably find an instruction manual included with it. Having carefully studied it, you will find that only a few general phrases are said about the correct inclusion. Is it really that simple? Plug the plug into the outlet and that's it? Alas, no.
An inverter-type welding machine is a complex device with its own nuances and features. By thoughtlessly plugging it into a household outlet, you risk losing the device itself or the wiring in the house. So how to connect a welding inverter correctly?
In this article we will briefly describe how to connect a welding machine to a 220 Volt home network and what should be taken into account.
How to connect a welding machine
Before welding, at a minimum, you need to understand how the welding machine is connected to the existing network, as well as what conditions must be observed.
To quickly and efficiently connect the welding machine, you should follow the current operating instructions for devices of this class.
Of greatest interest from the point of view of the features of this process is the connection of a welding inverter, most often used at home.
Safety regulations
The connection diagram for an inverter welding machine is quite simple and allows the device to operate in a cyclic (intermittent) mode, which allows for maximum welding efficiency. Before plugging into a socket, you still need to read the connection instructions, check the network parameters, completeness of the equipment and the external integrity of all its parts .
Options for connecting the inverter to the network
The instructions should clearly describe how to properly connect the welding machine, and also stipulate the procedure for its safe connection to the current electrical network. The need to check plugs and circuit breakers installed in the power supply circuit is specifically stated.
The fact that in old houses aluminum wiring does not allow working with currents above 10 Amperes should also be taken into account. Therefore, before connecting converters to the network, it is necessary to find out their rated power and current consumption.
When assessing the power taken from the network, one should not forget that when the device is turned on, there is a sharp surge in the starting current, the value of which can exceed the rated value several times.
Before connecting the device and welding work, the operator must fulfill the following requirements of the operating instructions:
- remove foreign electrical devices (computers, transmitters, measuring instruments) from the device body;
- when working with inverter equipment, the workplace must be cleared of all other interfering objects;
- The rooms in which the welding unit is located must be equipped with a forced ventilation system.
To avoid emergency situations, before connecting the welding machine for the first time, it is recommended to test it in various welding modes.
Turning on the device (operating instructions)
When considering the operating conditions of a welding inverter, first of all, you need to pay attention to the following points:
- the normal duration of the current load should not exceed 5 minutes;
- in practice, the so-called “three-minute cycle” is usually used, which is two-thirds of the full load;
- If strong heating of the case is detected, the device must be turned off until the causes of the overload are determined.
Welding using an inverter machine requires careful preparation, since dangerous situations are possible when working with equipment of this class. Before starting welding work, the operator must fulfill all the requirements of the operating instructions, including choosing the appropriate current mode and electrode type .
Connecting the inverter to the network and putting it into operation is allowed only after meeting safety conditions, including the use of sockets and plugs of the appropriate standard.
When operating a welding machine, you should use special coated electrodes (MMA type).
The thickness of MMA electrodes is selected based on the mode and type of metal to be worked with. Typically, the thicker the metal, the greater the current required and, accordingly, the diameter. The most common ones used at home are 2 and 3 mm electrodes.
Before starting welding, make sure that the electrodes are dry. The wire going to the torch is connected to the minus terminal, after which the gas hose is connected to the reducer located on the cylinder if welding is performed in a protective environment.
When connecting via an extension cord, you need to pay attention to the cross-sectional diameter of its cable. The cross-section must be at least 1.5 square meters. mm for working with current up to 16 A. The wire must be completely untwisted so that there is no inductance, which, after connecting the welding machine, will create additional resistance.
Launch Mode Features
The inverter is put into operation by pressing the “Start” button, which leads to a state of complete readiness for welding procedures. To start welding in a protective gas environment after connection, just slightly unscrew the torch valve, install the desired electrode and “strike” it on the workpiece to be welded.
When considering starting an inverter, the following must also be considered. The fact is that any inverter device is equipped with a soft start device that prevents the failure of the electronic elements of the circuit from a surge of current.
Despite such protection, current surges when turned on can reach values of the order of 40 Amperes, which are dangerous not only for the outlet, but also for the existing electrical network due to the strong “sag” of voltage.
During current surges within the above limits, the mains voltage may decrease (“sag”) from 220 to 130-140 Volts.
It is recommended to connect the power supply circuit of the device to the terminal contacts located directly on the distribution panel, where the grounding bus is also supplied separately. For a machine installed in an input device, such voltage drops are less dangerous.
The situation with inrush currents is significantly simplified when linear rather than phase voltages are used to power the inverter. However, this option can be implemented only for devices designed for 380 Volts and provided that the house is connected to a three-phase network (generator).
When considering the features of putting an inverter device into operation, one should not forget the features of adjusting its load current, which is carried out automatically (using a special control unit). Setting elements that set the control limits are located on the front panel of the device.
Compliance with the instructions for connecting pulse converters is mandatory for all models of welding devices without exception. Only if the starting conditions for inverters are met is it possible to maintain their functionality and guarantee high efficiency of the welding process.
Source: https://svaring.com/welding/apparaty/podkljuchenie-svarochnogo-apparata
DIY welding machine: simple assembly instructions
Due to the fact that ordinary people often need to work with metal in everyday life, many people use welding units. But not everyone can afford to purchase expensive equipment, which is why the question arises of how to assemble a welding machine with your own hands. The manufacturing process will differ depending on the type and design features of the welding device.
Types of Welding Machines
The modern market is filled with a fairly wide variety of welding machines, but not everything is advisable to assemble with your own hands.
Depending on the operating parameters of the devices, the following types of devices are distinguished:
- on alternating current - delivering alternating voltage from the power transformer directly to the welding electrodes;
- on direct current - producing constant voltage at the output of the welding transformer;
- three-phase – connected to a three-phase network;
- inverter devices - delivering pulsed current to the work area.
The first version of the welding unit is the simplest; for the second, you will need to modify the classic transformer device with a rectifier unit and a smoothing filter. Three-phase welding machines are used in industry, so we will not consider the manufacture of such devices for domestic needs.
An inverter or pulse transformer is a rather complex device, so to assemble a homemade inverter you must be able to read schematics and have basic skills in assembling electronic boards.
Since the basis for creating welding equipment is a step-down transformer, we will consider the manufacturing order from the simplest to the more complex.
AC
Classic welding machines operate on this principle: the voltage from the primary winding of 220 V is reduced to 50 - 60 V on the secondary winding and is supplied to the welding electrode with the workpiece.
Before you start making, select all the necessary elements:
- Magnetic core - stacked cores with a sheet thickness of 0.35 - 0.5 mm are considered more profitable, since they provide the least losses in the iron of the welding machine. It is better to use a ready-made core made of transformer steel, since the tightness of the plates plays a fundamental role in the operation of the magnetic circuit.
- Wire for winding coils - the cross-section of the wires is selected depending on the magnitude of the currents flowing in them.
- Insulating materials - the main requirement for both sheet dielectrics and the native coating of wires is resistance to high temperatures. Otherwise, the insulation of the semi-automatic welding machine or transformer will melt and a short circuit will occur, which will lead to breakdown of the device.
Source: https://www.asutpp.ru/kak-sobrat-svarochnyy-apparat-svoimi-rukami.html
Connecting the welding machine to the electrical network: rules and algorithm, safety precautions
Surely, after purchasing an inverter welding machine, in the box you will find instructions for operating the device. After reading it, you will most likely notice that proper connection to the network will be mentioned in passing.
And in vain, because the matter is not limited to simply inserting a plug into a socket.
It is dangerous to carelessly connect such complex equipment to your home network without taking into account its properties and nuances. As a result, you can easily destroy the welding inverter itself or the wiring in the building. What do you need to know about properly connecting a welding machine?
Below we briefly summarize the main points that you should pay attention to when connecting a welding inverter to a 220V household outlet.
Preparing to connect
Before connecting the welding inverter, you should make sure that the wiring in the building is suitable for welding work. First of all, inspect the outlets.
If they were installed more than a quarter of a century ago, then there is a good chance that the wiring has not changed since then. It’s good if it can withstand high voltage, but this is rather an exception to the rule.
Usually such wiring only adds difficulties to the work. In this case, you will not be able to work with a modern inverter machine, even using the latest welding cables.
You don't have to have an engineering degree to imagine the consequences of connecting a powerful inverter to an old outlet.
You risk cutting off power not only to your workspace, but also to neighboring buildings, and electrical appliances may become unusable.
Before starting work and connecting the inverter, it is necessary to check the condition of the wiring. Don't give up if you find out that your wiring may not be able to handle the load.
You can get out of this situation by using a current generator. How to do this is described below. Now we suggest considering options for connecting an inverter welding machine to the network.
Using Generators
If the wiring test result is unsatisfactory, connecting the inverter is unacceptable. But there is always a way out. Electric generators can be used.
Many people have gas generators that can help out in the absence of electricity. In theory, their use may seem like a great idea.
In fact, it turns out that such generators have low power, and supplying a voltage of more than 5KW is an impossible task for them.
Obviously, there is no point in connecting an inverter device to a generator with low power. The minimum required power value can be found by multiplying the cooking current by the voltage value.
Let's consider a standard connection diagram. When welding with a 3 mm electrode and a current of 120A and a voltage of 40V, you need to multiply 120 by 40. This means the required power value is at least 4.8 kW.
Considering that the efficiency of the inverter is less than 100%, for stable operation of the welding machine you will need at least 6 kW.
So, a gasoline generator can be used when no other power source is available. It is more logical to check the wiring at the planning stage of purchasing an inverter device.
If it does not meet the requirements, there is a solution to purchase a device with an already built-in generator. The only disadvantages of these models are the price and large dimensions. But sometimes there is no other way to solve the problem.
If this option is not relevant for you, pay attention to the current stabilizer for the welding inverter. You can connect the device to it in a relatively stable network.
Selecting extension cords
Particular attention should be paid to the use of extension cords when connecting inverters to the network. If the extension cord is incorrectly selected, the efficiency of the welding inverter decreases and the voltage drops.
The configuration of welding machines usually includes a cable about 2.5 m long. For simple work, this length is enough, but in case of frequent movement or welding at height, it will not be enough.
Therefore, it will not be superfluous to learn about connecting extension cables. Under no circumstances connect them at random! You will need to calculate the exact cross-sectional size of the extension cable.
This value is directly related to the maximum power that the wire can withstand.
Using the above diagram, let's give an example. The current we need when welding is 120A. We get 16A when using a cable with a cross section of 2.5 sq. mm.
Proportionally, for a welding current of 120A, the cross-section of the extension cable must exceed 12 sq. mm. Do not forget about safety precautions, remember about grounding and untangle the cables before starting welding, for faster cooling.
It is much more efficient to buy one cable of the required length than to connect several short ones to each other. This way, the contact connections of the extension cord will be more durable, and the possibility of losing the efficiency of the welding inverter will be reduced.
CONCLUSION
The described technology for connecting an inverter welding machine to the network is simple.
It is worth understanding the importance of these rules, remembering them and successfully applying them in practice in the future.
When connecting a transformer, semi-automatic device or 380V device, the sequence of actions is the same. Successful work!
Source: https://prosvarku.info/tehnika-svarki/kak-pravilno-vypolnit-podsoedinenie-svarochnogo-apparata-k-elektroseti
How to connect a welding machine: a practical guide
Machines with a welding current of up to 140 A can be connected to a 16 A household electrical outlet
The purchased semi-automatic machine has been successfully unpacked, wheels and handles for moving, if any, have been installed. It's time to put the equipment to work. How to properly connect the wires to an inverter welding machine and how to behave in order to avoid troubles in the form of fire or electric shock?
Before you start:
- Make sure the unit is located in a suitable location. Nothing should interfere with the air flow to the openings, and there should be no dust, damp or corrosive vapors in the immediate vicinity.
- Find out whether the frequency and voltage indicated on the device body correspond to the power supply. If your model allows it, lock the switch using the locking screw in the desired position - 220 or 380 V.
- Check the integrity and insulation of cables - flexible and fixed. There should be no twists or cracks on them, as they will cause overheating.
- Prepare an outlet with a fuse or circuit breaker.
"Old style" sockets rated for 10 A are often not suitable for welding.
Subtleties of connection
For inverter semi-automatic devices, “phase” or two “phase” wires are used in combination with “zero”, as well as green or yellow conductors for grounding. Power is supplied via a plug that meets thermal throughput standards. The return cable is connected to the ground terminal. To improve contact and avoid voltage losses, special tips are soldered to the latter.
In devices operated from a three-phase network, the first wire goes to the “phase” of the power supply, the second to the neutral output, and the third to the protective “zero”. Before connecting a household welding machine to a three-phase 380 V network, determine where the thin input ends are and where the thick output ends are. Then connect two of them to any two “phases”, the third to the protective “neutral” wire.
What you need to know about the cable
This is what a multi-core cable for connecting inverter semi-automatic devices looks like
For effective operation, it is necessary to select flexible cables of the correct cross-section and optimal length. Their characteristics must be such that the voltage during welding drops by no more than 2 V.
The optimal solution is multi-core copper cables of round cross-section, which facilitate work due to their flexibility. They are based on a current-carrying core up to 95 mm2, which contains many wires with a diameter of 0.18-0.2 mm. It is this modification, unlike the single-core one, that is suitable for both power connection and grounding.
The size of the cross-section is selected depending on the power of the inverter and the welding current. For example, a value of 16 mm2 is sufficient for 189 A, while an analogue of 95 mm2 is designed for operation up to 522 A. The optimal value is 35 mm2, aimed at household models up to 140 A.
The standard wire length of 1.8-2.5 m is usually not enough. It is important to choose the right material for the extension cord. For example, a cross section of 1.5 mm2 is designed for a maximum current of 16 A, and for 25 A sockets you will need an analogue of 2.5 mm2. The trend is this: the fewer intermediate connections, the more reliable and safe the welding.
How to deal with network problems
Ground terminal with lug
To protect semiautomatic devices from failure due to power surges, many use gas generators as a power source. However, the power of such devices is often not enough to operate.
Instead, you can connect the welding machine through a surge protector that protects against impulse noise, overloads and short circuits, or use a voltage stabilizer.
When choosing the latter, it is important to know which input on the electrical panel is single- or three-phase, and also to take into account the output power of the semi-automatic device and the range of changes in input voltages in the network.
And finally, a piece of advice. Do not connect the remaining components of the inverter semiautomatic device - a gas cylinder, a reel of wire - when the power is turned on. Press the “Start” button only when the complete set of equipment is ready for use!
Source: https://www.Toool.ru/articles/kak_podklyuchit_svarochnyy_apparat_prakticheskoe_rukovodstvo.html
