380 volt welding machines are common in manufacturing and construction due to their power and unpretentiousness. The use of three-phase devices allows you to work with electrodes of large diameters and metals of maximum thickness.
Welding in comparison with single-phase devices is softer. When working as part of production lines, three-phase equipment is also used.
Three-phase welding machines are of three types:
- transformer;
- rectifier;
- inverter.
Welding equipment of the first type is based on a three-phase transformer. The primary winding consists of three windings connected by a star, and the secondary step-down winding is connected by a delta.
If used for welding alternating current, then from each phase of the secondary winding, a reduced voltage is supplied to the electrode through a choke with a separate wire. Compared with a single-phase welding transformer, welding is softer, the electric arc becomes more stable, and the voltage drop is less.
Rectifiers at the output of the secondary winding have three half-bridge circuits assembled from powerful diodes. As in the first case, current is supplied from each rectifier to the welding electrode.
Pulsations in comparison with a rectifier in one phase are much less, respectively, the welding current is more stable, which affects the quality of welding.
In three-phase inverters with the same welding power, you can use less powerful diodes and transistors, but this is practically not done. On the contrary, the use of three-phase voltage makes it possible to obtain high-power devices with small dimensions and weight.
Advantages and disadvantages
All three-phase welding equipment belongs to the category of professional devices. Many of them are capable of welding in continuous mode, that is, the duty cycle is 100%. In construction, three-phase transformer and rectifier welding machines still have no alternatives.
They are not afraid of dust, dirt, they work at low temperatures, which is contraindicated for inverters. Single-phase transformer-type devices can also operate under the same conditions, but they have less power and more current ripple.
Accordingly, they cannot be compared with three-phase devices in terms of welding quality, electrode diameter and thickness of the metal to be welded.
The use of three-phase current in inverters also has its advantages. Using the same element base, a more powerful device with high welding currents is obtained, which allows you to work with almost any product.
The scheme of the device differs slightly. The same pulse-width modulator is used. The conversion of high to low voltage occurs at a frequency of about 40-100 kHz.
The only drawback of these devices is that it is not always and not always possible to connect to a three-phase 380 V power source, and their price is much higher than that of single-phase devices.
Popular Models
380 V is the most common device among professional devices. Unlike transformer devices, they have small dimensions and weight.
Welding semiautomatic device TESLA MIG 350 of Czech production has proven itself well when working in difficult conditions. With an unstable or low supply voltage, it provides a stable welding arc, operates on a voltage of 380 V, and the maximum welding current is 350 A.
The welding wire feed mechanism of the machine has two rollers, power consumption is 11.9 kW. The power reserve allows the use of long cables up to 20 m. Bayonet plugs provide a reliable and quick connection of the burner to the device. The manufacturer gives a three-year warranty on the equipment.
Another example of a professional three-phase inverter is Svarog ARCTIC ARC 315 (R14). It works in harsh conditions, allows you to cook in intensive manual mode, to perform surfacing. Thanks to the use of the latest inverter technology, the device can operate at temperatures down to -30 ⁰С. There is a "hot start" function.
Separate mounting of power transistors increases the maintainability of the device. With a maximum welding current of 315 A, the inverter can use electrodes with a diameter of 6 mm. This allows you to weld metals up to 17 mm thick. With a power of 12 kW, it has a mass of 22 kg.
Three-phase inverter welding machine"Resanta SAI-315 380V" has approximately the same characteristics as "Svarog", but fewer additional functions. It is simpler, therefore cheaper and weighs only 10 kg.
Connection
Unlike single-phase, equipment for welding using three phases has a four or five-pin plug at the end of the power cable. If the room has an appropriate outlet, you just need to connect the welding machine through it.
But, sometimes, especially in construction conditions, when there are no appropriate sockets, the ends of the cable are connected to the phases through a bolted connection. diesel generator or transformer substation.
When choosing equipment for welding in a home workshop and there is a three-phase power supply on the site, it is worth stopping at a three-phase welding machine. At the same time, it must provide manual arc welding modes and in shielding gases (MMA, MAG/MIG).
Then it will give almost unlimited possibilities in welding business. Since they are intended for professionals, they have many additional functions and settings.
As you acquire skills, you can learn new features of the device, which will undoubtedly be very useful for the owner. Unlike a single-phase device, it will not sag voltage during operation, distributing the load across all phases, and accordingly there will be no complaints from neighbors.
The welding inverter is a technological solution that implements a power circuit according to a new principle. As a result, a more stable operation of the apparatus is ensured, which is due to an easier process of ignition of an electric arc, as well as a high level of stability of its combustion.
Application area
Initially, welding work could only be carried out using two types of equipment: transformers and rectifiers. But each of these options is characterized by certain nuances that make their operation difficult, for example, large dimensions. Inverter devices primarily stand out from a number of similar equipment due to their relatively small size, which allows them to be freely used at home.
Another significant advantage of such devices is the possibility of application without special restrictions. So, the welding inverter is freely used in different types welding (electric arc, plasma). This can be a process of manual arc, argon-arc, plasma, semi-automatic welding. Devices of this type deservedly gained wide popularity due to their light weight and easy operation.
Overview of existing versions
The welding inverter is characterized by a phased energy conversion:
- the mains voltage supplied to the apparatus is rectified, for which a rectifier is provided in the design;
- direct voltage is converted back into an alternating equivalent, but with other characteristics - high frequency;
- then there is a decrease in the value of this parameter;
- the high frequency voltage is rectified again.
These difficulties in the process of operation made it possible to make the welding inverter small-sized, which made it possible to perform welding at home. The classification of such devices is carried out on the basis of differences in the operating current values:
- Household performance.
- Professional purpose.
- Industrial inverter devices.
Classification of inverters
Asking the question which of the options just named is better, you must first find out what their fundamental differences are. For example, household designs are more suitable for use at home, in a garage, as they are not designed for continuous use. If you select this option, the welding current will vary from 120 to 200A. And in most cases, 160 A is enough for work.
A professional device provides an operating current greater value: from 200 to 300A. Such an inverter can be used for continuous loads, for example, for welding pipes, in installation work.
An even more productive design option is industrial welding machines, which is due to a wide range of current values: from 250 to 500A. This technique is not intended for the home. In addition, there are different versions that differ in the nature of the current: single-phase and three-phase version.
What parameters to pay attention to
First of all, the tasks that are planned to be solved with the help of equipment of this type are determined. If necessary, such devices are usually designed for 20-30 minutes. welding, after which you need to take a break. Next, a model with a suitable operating current range is selected. This parameter is affected by the quality of the mains voltage: the less stable it is (read, it drops lower in value, for example, up to 210V), the higher the welding current is required.
Under these conditions, it is necessary to pay attention to 200A welding machines. In addition, when choosing such equipment for the home, one should also take into account the thickness of the metal with which it is planned to work: the higher the value of this parameter, the greater the welding current should be.
It is also taken into account on the "phase" of the device. If you choose a single-phase version, you can connect it to the mains through a regular socket. Three-phase versions, in turn, provide a higher quality of work. Another important parameter is the wire feed method. You can choose an inverter for the house with a built-in mechanism, but there are models with a remote wire feed unit.
Among other parameters, the range of electrode diameter values declared by the manufacturer, with which the device can work, is also taken into account. It is equally important to pay attention to additional features, for example, whether there is protection against voltage surges. Most of these devices are also characterized by the "anti-sticking" "forced start" function.
Top Producers
When deciding for yourself which option is better to choose, you should also consider the brand of the device. One of the leaders is the manufacturer FUBAG. The main feature of its products is a very wide range of supply voltage: from 85 to 265V. In addition, the design provides for special protection, which makes the welding inverter for the home practically insensitive to power surges.
FUBAG manufacturer
The best devices of this type are produced by Brima. This brand has been on the market for a very long time. And the popularity of products is due to the high quality of welding, which is not affected by fluctuations in the network. If a short circuit occurs during operation, the voltage will drop to a minimum. Another famous brand is Kemppi. But it is quite possible to choose Russian analogues of this type, for example, Fast and Furious, Neon.
Their distinguishing feature is high-quality components, a complicated design. If the task is to choose a welding machine for the home, in some cases it is better to turn to Russian versions, in addition, their cost is lower than foreign counterparts.
Nuances of operation
The operation of such a technique is designed for certain conditions. Typically, the manufacturer specifies the range of temperatures at which welding is allowed. In addition, you need to work intermittently. If the welding machine is turned on in hot weather (30-40 degrees), the duration of work should be less, and the “rest” time of the machine, on the contrary, increases.
In some models, the fan automatically turns on only when heated. Relying on the automatic shutdown of the device in case of overheating is not worth it, because there is a risk of the temperature sensor failing and then you may not know that it's time to take a break.
The inverter for the home is selected based on the degree of protection, respectively, the device should be operated in dusty areas very carefully. It is necessary to control that water does not get inside as well. When connecting the device, it is recommended to avoid too long cables (more than 5 m), as well as unsuitable wires (less than 1 sq. mm).
Periodically, the apparatus is blown with compressed air, which allows you to remove accumulated dust. It is better to check the connection of the welding cable (current inserts), otherwise they may burn, and monitor the condition of the wire insulation.
Thus, for work at home, it is necessary to select inverter versions within the operating current of not more than 200A, sometimes a smaller value is quite enough. The most popular model is the 160A. When deciding which option is better, you should pay attention to the brand of the product, the current flow (single-phase, three-phase), as well as the wire feed method, and the presence of additional functions. But careful operation will help extend the life of the device.
Kuvalda.ru online store offers three-phase welding inverters that meet the requirements and quality standards. With us you can pay for goods by bank transfer or in cash, as well as by card. The catalog of three-phase welding inverters is constantly expanding and supplemented with the latest models. In our online store there is a convenient and fast delivery in Moscow and the Moscow region. To quickly search for products, use the search function by categories, sections and subsections, as well as in the search bar by search word or number. Experienced managers will help you navigate the presented goods and tell you technical details and delivery terms. With a wide range of three-phase welding inverters, you will find everything you need with us. We are happy to answer your questions about our prices and range. We welcome your suggestions and wishes to improve our service.
Scheme of connecting a 3-phase network to the inverter Svarog TIG 200P AC_DC
The algorithm of work will be as follows:
1. If you plug in a standard plug into 220v, then the K1 starter (25A per contact) is activated, which with one pair of contacts restores the wire we cut that goes to the ON / OFF switch of the welding machine.
And its second pair of contacts will close the cuts we made on the tracks on the printed circuit board, which supply power to the standard single-phase full-wave rectifier.
K1 is not needed for anything else. It only restores the original power circuit of the welding machine after cutting two wires and two tracks. (although, there is one more function - K1 does not allow the regular plug of the welder to be energized when it is connected to a three-phase power supply. This is very good!)
2. Starter K2 (10A per contact) is used to connect the three-phase power supply to the circuit of the device. It is smaller and cheaper, since it requires only two wires to be shorted, which we will pass through paired 10A contact groups. Actually, that's all.
First, I bought three-phase sockets 3p + N + E, which means four phase and zero contacts and a fifth earth. I bought a four-core wire with a diameter of 2.5 mm per core. I planned to place the rectifier diodes on the radiator inside the SvarAppa. However, in the process of work, I came up with a more elegant and safer solution.
The point was that I would place a 3-phase rectifier in a separate box directly next to the input shield, and the already rectified voltage would be connected to the welding start through one wire, through the second any of the phases to the SvarAppa electronics start-up circuit (no way without it), through the third start NULL, and I still have a fourth wire, through which I will attach a real honest EARTH from the input shield to the body of the device (I actually have it in the input shield).
Thus, I get to provide all types of security for the user and svarAppa, plugs and sockets can be supplied with four pins, i.e. 3p+E. I found this more convenient.
So that the diodes were not "day and night" energized in the shield, and for convenience, of course, I connected them through a cheap 40A load switch. This is not an automatic machine, they are enough along with the RCD in the main shield, it's just a three-pin switch. Diodes are suitable “for every taste and color”, I had D242B from one batch in the garbage, I paralleled them and screwed them onto the radiator from some old computer processor.
He took copper wires, also collected scraps on the farm, those that were thinner folded in pairs - at one end into a screwdriver and twisted: it comes out beautifully with a hard pigtail. The total cross section of copper is enough 2mm2. Doesn't make much sense anymore. It is very convenient to take copper in one thick strand. It will immediately serve as a rigid construct and is more competently clamped in the terminal blocks. Yes, and prepare a 60-100 watt soldering iron to do the assembly culturally where necessary, we are not Chinese.
Now, we call on all our attentiveness to help and do as I said:
(for those who are still swimming in our topic and have forgotten the rules of sapper technology)
STEP 1.
Upgrade STEP 1
We place the 25A starter in a place convenient for it (we don’t even fasten it if we have hard wires), we estimate by eye at what distance it is better to cut the phase and neutral in a condom, going to the ON / OFF switch and ... feel free to cut it down with a checker!
We clean the resulting stumps from the braid, beautifully tin them and clamp them in the two upper K1 terminal blocks in the photo.
Hint - before step 1, prepare and screw a suitable wire to coil K1 and immediately solder it to the ends of the neutral and the phase coming from the RF noise filter (this is the lower cut piece in the photo).
Feel free to clamp these ends on the starter coil terminals in any
okay. If you have done step 1, then you can plug the welder's wire into the outlet and make sure that it continues to work as before, the only thing that annoys us at first is that when the wire is plugged into the outlet, the starter clicks. From this at first you shudder, but then you get used to it.
Upgrade STEP 2
We take in hand hacksaw blade and carefully, at least 1.5 mm wide, deeper into the textolite, cut the tracks that go to a pair of fours of yellow wires in the connectors. Closer here, pay attention - the yellow small circle around the varistor contact, which we cut (the black dash indicates the former track). And the red stripe is a jumper that you must remember to solder later! Otherwise, transient impulse voltage surges will not be extinguished.
On the right, the contacts of the relay (white) are circled in an oval, which closes with some delay after power is applied to the svarApp. This, in fact, is all the control points that our attention will be drawn to in the manipulations further. And then - we lay out the wires from K1 in order to close the section made by us with its contacts. Without completely turning off the head, we trust our direct handles ...
Here we laid it out, and here the ends were soldered. (DO NOT FORGET THE JUMPER FROM THE VARISTOR! Not visible in the photo?)
We turn on the device again and make sure that it is fully working from a single-phase network.
And now, a simple, but very crucial moment. We solder to the ends of the cut tracks (the leftmost ones in the photo, going to the rectifier) a two-core, not thick wire that goes to the K2 coil. We connect the K2 contacts in pairs with four short (orange) jumpers.
In the photo, we twist the right contacts of K2 with short wires and clamp them together with the contacts of K1, going to the same place where the wire was thrown onto the K2 coil.
The wire that in “ordinary life” goes first to the “white relay” is black, we will put it on it (in three-phase connection) any phase chosen by us for powering the starting electronics of svarAppa. And the wire that goes without a break from ON / OFF (thick red) to the regular rectifier through the yellow leads in the white connectors, we solder with the NULL wire from our three-phase socket.
We carefully look at the diagram and, with a smart facial expression, poke the tester into the terminals, checking the compliance of the wiring diagram with the diagram.
If you are completely convinced that “everything is according to the scheme”, then carefully assemble / bend the reins with K1 and K2, put SwarApp inside, admire and once again make sure that it still works from one phase! Don't be lazy..
Upgrade STEP 3
STEP 3. The most interesting and exciting.
I first made it right on the operating table. The blue braided wire trimmed by the frame of the frame is soldered to the braided yellow / blue and screwed to the radiator (plus) of the three-phase rectifier (it is temporary). This power plus goes to the paired contacts of the K2 starter (it is clearly visible in the photo). On K1 from a 3-phase socket there is a pair of phase \ zero and power zero.
ATTENTION!
I remind you that on this PHOTO there is a socket with 5 pins, later, when I put the rectifier into the shield, the socket will be four-pin. (see diagram)
SO, we supply three phases to a homemade welding machine, and switch ON / OFF to ON! Starters clicked .... And everything worked!!
Upgrade STEP 4
We plug in the power cables, unscrew ..
Wow! on the 202A current handle, in the barn we find the thickest and oldest electrode. This turned out to be rotten in mold from the time of perestroika 4-ka.
Homemade Three-Phase Welder: STEP 4 - Homemade Welding
We grab a black piece of iron, in the place where it is 10 mm thick, shamelessly rest and crush the electrode ... In the first instant, it sticks, water with mushrooms boils out of it with a hiss (really, it smells like soup!) and ...... with full pressure, a second in three or four we burn a through hole! We are experiencing the first joy / pride, and the next couple of evenings we are already thoughtfully and slowly experimenting with our charm in different poses and modes ... ..
Upgrade STEP 5 (Cleaning and packing the assembled circuit)
Carefully and finally lay the wires, starters. Sparing no effort, we will pull in different directions, simulating a hard fall of svarAppa from the roof. If no starter touches the surrounding glands with contacts, then everything is reliable with us.
The final touch - we tighten where possible, with harnesses (I had green ones, I don’t remember where I expropriated). We admire, and take on the design of the output of wires for a three-phase outlet.
We bring four wires approximately to the center of the top of a homemade three-phase inverter. This is a + 250v wire from a three-phase rectifier, NULL, any one phase, and we fasten the yellow wire with a green stripe to the device case, this will be our “honest land”. We remove a small piece of braid from the power cable and wrap it around all the cables in the place where they will pass through the hole in the inverter cover, well, and wrap it with insulation.
Below is a photo of new four-pin sockets / plugs, a 40A load switch and a cozy house for a radiator with rectifier diodes from MAKEL (by the way, with a poetic name - “siva-ostyu-sigorta-kutusyu”). In Russian, more and more prosaic - Electrical panel Invoice.
We drill a hole in the cover of the welder with the 14th drill for the output of our power leads, fasten one of the sockets, fasten the ends of the wires, etc. etc…
Here's what happened:
Homemade three-phase welding machine: What happened ...
Homemade three-phase inverter from Svarog
We are preparing the connection of the second outlet and the shield with the rectifier and the load switch, we check with the tester that there is no tangling of wires in the sockets and we go to screw the shield onto the wall.
That's what happened in the "shield".
The right connector - there is a 3ph + N + E socket - this is for connecting conventional 3-phase devices. But the left one is exclusively for our charms.
On this, in fact, everything. At the moment, I burned an argon cylinder while playing with swarApp in 3 phases. Works flawlessly.
See in store reviews:  SVAROG ARC 205 CASE, welders about the operation of the machine — check if there is a discount on the device today — find reviews of other equipment. |
Answer:
Only one thing can be said for sure - there are no household three-phase inverters, so you are going to purchase a model of a semi-professional or professional level. These models are characterized;
. A large range of output welding current (up to three hundred amperes for semi-professional devices and over three hundred amperes for "professionals");
. The ability to cook metal of great thickness (up to 1 centimeter for semi-professional models and very thick for professional inverters);
. The ability to work with different thicknesses of electrodes (for household models, the wire diameter is limited to 4 millimeters, and most often the welder is forced to work with a “troika”);
. Greater functionality (including a variety of protection functions and functions that increase user convenience in the process of work);
. Higher level of protection from external influences;
. Large weight and dimensions (the weight of a "professional" can reach 50-60 kilograms, while household welding inverters weigh on average from 4 to 7 kilograms);
. The higher cost of the equipment itself.
Be that as it may, three-phase welding machines open up huge opportunities for the welder and sometimes allow you to work real miracles. If you really want to purchase a three-phase welding inverter and the budget allows you to do this, then it is better to choose a professional model from a well-deserved domestic or European manufacturer. Among domestic "professionals" we advise you to make a choice in favor of. And if you prefer a European instrument, then ideal solution become Finnish.
If the budget is not designed for a professional model, and there is no point in buying it, then look for a semi-professional three-phase welding inverter among or. Yes, and in the range of Svarog and Kemppi there are also quite worthy semi-professional tools, it's just that FoxWeld, for example, has a larger selection of such equipment.
