How to properly connect a Resanta welding machine

Do-it-yourself repairs and modifications to welding inverters

The characteristics of most budget inverters cannot be called outstanding, but at the same time, few will refuse the pleasure of using equipment with a significant margin of reliability. Meanwhile, there are many ways to improve an inexpensive welding inverter.

Typical circuit and principle of operation of the inverter

The more expensive the welding inverter, the more auxiliary units in its circuit that are involved in the implementation of special functions. But the power converter circuit itself remains virtually unchanged even with expensive equipment. The stages of transformation of mains electric current into welding current are quite easy to trace - at each of the main nodes of the circuit a certain part of the overall process occurs.

From the network cable, through a protective switch, voltage is supplied to a rectifying diode bridge coupled with high-capacity filters. In the diagram, this area is easy to notice; there are impressive-sized “banks” of electrolytic capacitors located here. The rectifier has one task - to “turn” the negative part of the sine wave symmetrically upward, while the capacitors smooth out the ripples, bringing the direction of the current almost to a pure “constant”.

Scheme of operation of the welding inverter

Next in the diagram is the inverter itself. This part is also easy to identify; the largest aluminum radiator is located here. The inverter is built on several high-frequency field-effect transistors or IGBT transistors.

Quite often, several power elements are combined in a common housing. The inverter again converts direct current into alternating current, but at the same time its frequency is significantly higher - about 50 kHz.

This chain of transformations allows the use of a high-frequency transformer, which is several times smaller and lighter than a conventional one.

The output rectifier removes the voltage from the step-down transformer, because we want to weld with direct current. Thanks to the output filter, the nature of the current changes from a high-frequency pulsating current to an almost straight line. Naturally, in the considered chain of transformations there are many intermediate links: sensors, control and control circuits, but their consideration goes far beyond the scope of amateur radio electronics.

Design of the welding inverter: 1 - filter capacitors; 2 - rectifier (diode assembly); 3 - IGBT transistors; 4 - fan; 5 - step-down transformer; 6 — control board; 7 - radiators; 8 - throttle

Units suitable for modernization

The most important parameter of any welding machine is the current-voltage characteristic (CVC), which ensures stable arc burning at different arc lengths.

The correct current-voltage characteristic is created by microprocessor control: the small “brain” of the inverter changes the operating mode of the power switches on the fly and instantly adjusts the parameters of the welding current.

Unfortunately, it is impossible to reprogram a budget inverter in any way - the control microcircuits in it are analog, and replacement with digital electronics requires extraordinary knowledge of circuit design.

However, the “skills” of the control circuit are quite enough to level out the “crookedness” of a novice welder who has not yet learned to hold the arc stably. It is much more correct to focus on eliminating some “childhood” diseases, the first of which is severe overheating of electronic components, leading to degradation and destruction of power switches.

The second problem is the use of radioelements of questionable reliability. Eliminating this drawback greatly reduces the likelihood of breakdowns after 2–3 years of operation of the device. Finally, even a novice radio engineer will be quite capable of implementing an indication of the actual welding current to be able to work with special brands of electrodes, as well as carry out a number of other minor improvements.

Improved heat dissipation

The first drawback that plagues the vast majority of inexpensive inverter devices is a poor heat removal system from power switches and rectifier diodes. It is better to begin improvements in this direction by increasing the intensity of forced airflow.

As a rule, case fans are installed in welding machines, powered by 12 V service circuits. In “compact” models, forced air cooling may be completely absent, which is certainly nonsense for electrical equipment of this class.

It is enough to simply increase the air flow by installing several of these fans in series. The problem is that the “original” cooler will most likely have to be removed.

To operate effectively in a sequential assembly, fans must have an identical shape and number of blades, as well as rotation speed. Assembling identical coolers into a “stack” is extremely simple; just tighten them with a pair of long bolts along diametrically opposite corner holes.

Also, do not worry about the power of the service power supply; as a rule, it is enough to install 3–4 fans.

If there is not enough space inside the inverter housing to install fans, you can attach one high-performance “duct” to the outside. Its installation is simpler because it does not require connection to internal circuits; power is removed from the power button terminals. The fan, of course, must be installed opposite the ventilation louvers, some of which can be cut out to reduce aerodynamic drag. The optimal direction of air flow is towards the exhaust from the housing.

The second way to improve heat dissipation is to replace standard aluminum radiators with more efficient ones. A new radiator should be selected with the largest number of fins as thin as possible, that is, with the largest area of ​​​​contact with air. It is optimal to use computer CPU cooling radiators for these purposes. The process of replacing radiators is quite simple, just follow a few simple rules:

1. If the standard radiator is isolated from the flanges of the radio elements with mica or rubber gaskets, they must be preserved when replacing.
2. To improve thermal contact, you need to use silicone thermal paste.
3. If the radiator needs to be trimmed to fit into the case, the cut fins must be carefully processed with a file to remove all burrs, otherwise dust will accumulate on them abundantly.
4. The radiator must be pressed tightly against the microcircuits, so you first need to mark and drill mounting holes on it; you may need to cut a thread in the body of the aluminum base.

Additionally, we note that there is no point in changing the piece heatsinks of separate keys; only the heat sinks of integrated circuits or several high-power transistors installed in a row are replaced.

Welding current indication

Even if a digital current setting indicator is installed on the inverter, it does not show its real value, but a certain service value, scaled for visual display. The deviation from the actual current value can be up to 10%, which is unacceptable when using special brands of electrodes and working with thin parts. You can get the actual value of the welding current by installing an ammeter.

A digital ammeter of the SM3D type will cost around 1 thousand rubles; it can even be neatly built into the inverter housing. The main problem is that measuring such high currents requires a shunt connection.

Its cost is in the range of 500–700 rubles for currents of 200–300 A.

Please note that the type of shunt must comply with the ammeter manufacturer's recommendations, typically 75 mV inserts with an intrinsic resistance of about 250 μΩ for a measurement limit of 300 A.

The shunt can be installed either on the positive or negative terminal from inside the housing. Typically, the size of the connecting bus is sufficient to connect an insert about 12–14 cm long. The shunt cannot be bent, so if the length of the connecting bus is not enough, it must be replaced with a copper plate, a pigtail of cleaned single-wire cable, or a piece of welding conductor.

The ammeter is connected with measuring outputs to the opposite terminals of the shunt. Also, for the digital device to operate, it is necessary to supply a supply voltage in the range of 5–20 V. It can be removed from the fan connection wires or found on the board at points with potential for powering control chips. The ammeter's own consumption is negligible.

Increasing duty cycle

The on-time duration in the context of welding inverters is more reasonably called the load duration. This is the part of the ten-minute interval in which the inverter directly performs work; the remaining time it must idle and cool.

For most inexpensive inverters, the actual PV is 40–45% at 20 °C. Replacing radiators and an intensive airflow device can increase this figure to 50–60%, but this is far from the ceiling. A PN of about 70–75% can be achieved by replacing some radioelements:

1. The capacitors around the inverter keys must be replaced with elements of the same capacity and type, but designed for a higher voltage (600–700 V);
2. Diodes and resistors from the key harness should be replaced with elements with higher power dissipation.
3. Rectifier diodes (valves), as well as MOSFETs or IGBT transistors, can be replaced with similar, but more reliable ones.

It is worth talking about replacing the power switches themselves separately. First, you should rewrite the markings on the element body and find a detailed datasheet for a specific element. According to the passport data, choosing an element to replace is quite simple; the key parameters are the limits of the frequency range, operating voltage, the presence of a built-in diode, type of housing and current limit at 100 °C.

It is better to calculate the latter yourself (for the high-voltage side, taking into account losses on the transformer) and purchase radioelements with a maximum current reserve of about 20%. Of the manufacturers of this type of electronics, International Rectifier (IR) or STMicroelectronics are considered the most reliable.

Despite the rather high price, it is highly recommended to purchase parts from these brands.

Winding the output choke

One of the simplest and at the same time most useful additions to a welding inverter will be the winding of an inductive coil that smoothes out the DC ripples that inevitably remain when the pulse transformer is operating. The main specificity of this idea is that the choke is made individually for each individual device, and can also be adjusted over time as electronic components degrade or when the power threshold changes.

To make a choke you will need nothing at all: an insulated copper conductor with a cross-section of up to 20 mm2 and a core, preferably made of ferrite. Either a ferrite ring or an armored transformer core is optimally suited as a magnetic core. If the magnetic core is made of sheet steel, it needs to be drilled in two places with an indentation of about 20–25 mm and tightened with rivets in order to be able to cut the gap without any problems.

The choke begins to work starting from one full turn, but the real result is visible starting from 4–5 turns. During testing, turns should be added until the arc begins to stretch noticeably strongly, preventing separation. When it becomes difficult to cook with separation, you need to remove one turn from the coil and connect a 24 V incandescent lamp in parallel with the choke.

Fine-tuning the throttle is done using a plumber's screw clamp, which can be used to reduce the gap in the core, or a wooden wedge, which can be used to increase this gap. It is necessary to ensure that the lamp burns as bright as possible when igniting the arc. It is recommended to manufacture several chokes to operate in ranges up to 100 A, from 100 to 200 A and more than 200 A.

Conclusion

It is better to mount all “mounted” additions, such as a choke or an ammeter, with a separate attachment, which is connected to the gap of any of the welding conductors using a bayonet-type plug. This way, enough space for ventilation will remain inside the inverter housing, and additional devices can be easily turned off when not needed.

It must be remembered that it will not be possible to carry out a radical, deep modernization, in other words, “RESANTA” cannot be turned into KEMPPI by reasonable forces and means. However, making fixtures and minor modifications to equipment is a great way to better learn arc welding technology and gain insight into professional intricacies.

Source: https://rmnt.mirtesen.ru/blog/43106358257

Welding inverter Resanta SAI-250

Passport (instructions) Resanta SAI 250PN . passport-instrykciya-resanta-sai-_250 DOWNLOAD

Resanta SAI-250PN is a welding inverter, one of the most popular on the market.

All models of inverter machines " SAI-250 PN " received protective mechanisms against temperature overheating, and also have the anti-sticking function "ANTI STICK", the ability to adjust "ARC FORCE", and the hot start " HOT START ".

Resanta Sai 250

Packaging, power cables and appearance of the Resanta Sai-250

This device is easy to set up and operate. Thanks to the use of all the necessary functions such as: anti-sticking of the electrode, easy ignition of the arc, high VA value.

These parameters greatly facilitate the process of joining metal, allowing even an inexperienced welder to achieve a good metal seam. The SAI-250PN inverter welding machine is lightweight and small-sized, and has a well-adapted carrying handle on top.

It will be easy for the welder to install and will make him mobile on the job site.

Handle on top of the device

Characteristic features of Resant

Resanta SAI-250PN can weld at reduced voltage. In case of network fluctuations, the inverter shows its best side, providing high stability of the set parameters of the welding process.

The inverter machine is designed for manual welding with a coated electrode using direct current.

Resanta 250 professional is an energy-efficient welding machine due to its high energy conversion efficiency.

If we compare SAI 250 with conventional transformers, then this type will benefit from the ease of setting parameters and maintaining a weld.

Settings panel and protective glass

Manuals and instructions for the inverter

Beginner's Guide to Arc Welding

Passport instructions for Resanta SAI 250PN .

Device delivery set

Cable with ground terminal for base metal

Cable with electrode holder for manual welding 2m.

Passport products

Inverter welding machine Resanta SAI 250PN directly

Measurement SAI-250

Resanta Sai 250: technical specifications

Possible voltage range, V 140-240

This will allow you to power the device from a regular household single-phase network.

Maximum possible current consumption, A 35

Possible open circuit voltage, V 80

Welding arc voltage, Volt 29

Current regulation range, A 10-250

Inverter load duration, % 70% 250A

Electrode diameter, mm up to 6, which also sets the inverter apart from its competitors;

Device protection class IP 21

Device weight, kg 6.7

Dimensions Resanta 250 dimensions, cm: 25 x 13 x 40 cm

Packaging (HxWxD), cm 43 x 17 x 29 cm, weight 8 kg

Firm Resanta

Country of origin People's Republic of China

Convenient on/off switching of the welder

Appearance and dimensions

The Resanta 250 welding machine has the highest power among the range of similar inverters. In addition, its small dimensions make it extremely convenient for transportation. The inverter can easily fit into the trunk of a car. It won’t be a significant burden as hand luggage either. This is especially true if you compare it with a conventional transformer.

Cables and sockets "Resanta SAI"

The Resanta-250 inverter is designed in a classic metal case with dimensions of 25 x 13 x 40 cm.

The front panels have a standard group of indicators and adjustment knobs for modern inverters. There are also working connectors, which include:

— “device overheating” indicator;

— “network” indicator;

— power sockets for connecting various welding cables .

— setting the welding current ;

In order to avoid overheating of the Resanta SAI-250 welding inverter, the developers equipped it with a forced air cooling system, since welding generates a large amount of heat inside the device. From the outside it is easy to notice the fan grille of this cooling system.

https://www.youtube.com/watch?v=8dR1RfoteHc

Setting the welding current

"Resanta-250" is no different from its relatives from other manufacturers in terms of its operating principle. First, the alternating voltage coming from a regular household network of 220V is converted into constant up to 400V, which is subsequently converted to a modulated high-frequency voltage. After which the step-down transformer reduces the resulting converted voltage to the required operating setting.

To improve the quality of welding work, as well as ease of use, this Resanta-250 model received a number of additional functions to ensure a good level of work.

Add-ons included: Arc Force function - adjustable arc force, "Anti Stick" and "Hot Start".

In order for the user to get a durable and high-quality seam from the very beginning of work, the creators of the inverter implemented the “Hot Start” . The essence of the function is as follows: at the moment the arc is ignited, the device supplies increased welding current, which immediately returns to normal. This makes the task of igniting the arc easier.

In addition, “Anti stick” should be mentioned. This function helps well to protect the electrode from a fairly common problem among welders - sticking of the electrode to the base metal.

Do not ignore safety rules when working with the device. If there is high humidity in the room, work should be abandoned, taking into account the electrical housing of the Resanta Sai 250.

During operation of the device, shavings and various metal dust quite often get in, which often leads to a short circuit. You should stop using grinders and other similar tools to drive the inverter. Don't forget about power cables, they also need care. Power cable length - 1.9 m Cable length with electric holder - 3 m

repair and review of the welding inertor "Resanta-250":

Resanta SAI-250 inverter circuit

Electrical circuit diagram of the welding inverter Resanta - 250 

Scheme RESANTA_SAI-250 DOWNLOAD

Cleaning the internal circuitry of the Resanta SAI-250

The welding inverter " Resanta - 250 " is made in a classic metal case and has on the front panel a number of indicators and adjustment knobs, as well as working connectors. These include: - "network" indicator; - "overheating" indicator; - current adjustment;

— power connectors for connecting welding cables.

Since when performing welding work, despite the inverter design of the unit, a significant amount of heat is generated, “ Rosanta-250 ” is equipped with a forced cooling fan, the grille of which is visible during external inspection of the product.

The principle of operation of the welding inverter "Resanta - 250" does not differ from similar devices from third-party manufacturers. The incoming alternating voltage of the household electrical network 220V is first converted to a constant voltage of 400V, which is subsequently changed to high-frequency modulated voltage. Next, a step-down transformer comes into operation, which lowers the converted voltage to operating voltage.

To improve the quality of work, as well as to obtain greater comfort during welding work, the welding inverter “Resanta - 250” “Anti Stick” and “Hot Start” functions

The “Anti stick” function, as the name implies, prevents the electrode from sticking to the surface of the materials being welded. That is, when the arc is ignited, the welding current automatically decreases, which is instantly restored after the electrode comes off.

And in order to get a beautiful and durable seam immediately after starting welding, the machine has the “Hot Start” function. In this case, at the moment the arc is ignited, there is a short-term increase in the welding current, which immediately decreases to the normal, required state.

Promotion of the resent with a screwdriver

When working with the Resanta-250 welding inverter, you must follow safety precautions. So, since the device is made in a metal case, it is strictly forbidden to use the latter in high humidity.

Do-it-yourself Resanta renovation

Chips and metal dust that get inside can damage the electronic part or even cause a short circuit. Therefore, the use of grinders and similar tools near the welding inverter is prohibited. And, of course, it is necessary to monitor the condition of the power and supply wires.

welding inertor "Resanta - 250":

Source: http://svarak.ru/oborydovanie/734/

How to connect a welding inverter to a power source?

A welding inverter is a device that can greatly facilitate the arc welding process. Every year its use becomes more and more popular, because it allows welding of any structures quickly and efficiently. In order for welding work to take place in the required modes, and for the device to have a long service life, you need to correctly connect the inverter to the power source. Therefore, further we will consider how to properly connect a welding inverter.

Diagram of the device of an inverter welding machine.

Connecting a welding inverter

The welding machine can be connected to an external network with a voltage of 220 V or 380 V, or to a generator set of a certain power. The connecting cable with plug corresponds to the maximum power of the unit, so there should be no questions here. The main difficulties may arise from an external power source, especially if the electrical wiring in the summer cottage is old and has an unknown cross-section.

Modern wiring, plugs and sockets are designed for a current of no more than 16 A. The total power consumed by all devices in the house can be more than this value, so it is limited by an automatic safety device or a regular plug. To connect a welding inverter, you first need to make sure that its input power will not disable the home network protective device.

Welding inverter device.

One of the advantages of this type of welding devices is that their electrical circuit has several types of protection. In case of network overload, the protection automatically turns off the device due to low voltage. This situation can occur when the input voltage is low, or in the case of insufficient electrical wiring, the resistance of which will reduce the voltage when a load in the form of welding current occurs.

If the electrical wiring of a fixed network does not allow connecting an inverter, you need to use other power sources, which will be discussed below. If the maximum power of the device fully matches the external wiring, you can connect the inverter to the mains and carry out test welding.

It is not recommended to connect to the network if a fuse of unknown rating is installed as a protective device.

If possible, you need to control the voltage drop when igniting the arc. Severe subsidence may be the result of a small cross-section of wires.

Also read: All about construction tools from A to Z.

Connecting a welding inverter to an electric generator

Due to poor parameters of the external electrical network, in some situations it is simply impossible to carry out welding. Then you can use the power plant. At the same time, it is very important that the power of the power plant allows for full-scale welding work.

When choosing a generator, you should first familiarize yourself with the basic technical characteristics of the welding machine. As an example, we will take a conventional inverter with an operating current of 160 A. Modern inverters have smooth adjustment of the welding current from minimum to maximum value. This allows welding to be carried out at both medium and maximum power of the equipment. But manufacturers often write only power consumption, without saying anything about its maximum value.

Figure 1. KG brand wires are different and differ in maximum load, depending on the cross-section.

To independently calculate the maximum power, you need to multiply the maximum operating current of the device by the arc voltage (usually it is 25 V), and then divide the resulting figure by the efficiency of the inverter (approximately 90%). As a result, the maximum power will be equal to: 160x25/0.9=4444 W.

After making the calculations, you can begin to select an electric generator. In this case, you should focus on the maximum power consumption, adding a reserve of 25% to it, so as not to use the power plant to its maximum capacity. Therefore, for a welding inverter with an operating current of 160 A, you need to buy a generator with an output power of at least: 4444+4444x0.25=5555 W, or 5.5 kW.

Gasoline generator or electric generator?

Connection diagram of the inverter to the battery.

In some cases, if it is impossible to use an external power supply, welders try to connect inverter welding through a low-power gas generator. This approach is incorrect if its power is less than 5 kW. The operating voltage in such generators strongly depends on the load size. Inverter devices are sensitive to voltage changes, so if the output voltage of the gas generator changes frequently, the welding machine may fail.

When welding with a 3 mm electrode, the operating current reaches 120 A at a voltage of 40 V. In this case, the output power will be: 120x40 = 4800 W, or 4.8 kW, that is, the gas generator will operate at maximum power, which will also lead to its premature exit building. Therefore, if the network is poor, it is better to connect the welding machine to an electric generator.

Selecting a cable to connect the inverter

To carry out high-quality welding, it is very important to choose the right connecting wires. Welding wires are selected according to the following indicators:

Functionality of the welding inverter.

• length;
• cross-sectional area;
• the value of the voltage drop in the welding circuit.

The inverter cable is a flexible current conductor with good insulation. In most cases, such a wire is made of copper wires 0.18-0.2 mm thick, woven together. Such cables are used to connect the inverter to the electrical holder, as well as to ground the device. The choice of wires depends on their technical characteristics and the characteristics of the welding unit itself.

Among welders, the most popular is the KG brand wire (Fig. 1). Manufacturers of this type of cable recommend its use in alternating current circuits with a voltage of no more than 600 V or in direct current circuits with a voltage of no more than 1000 V.

KG brand wires vary in maximum load, depending on the cross-section. The ratio of the maximum load on the cable and its brand is presented in the table:

Cable brand	Permissible load, A
KG 1x16	189
KG 1x25	240
KG 1x35	289
KG 1x50	362
KG 1x70	437
KG 1x95	522

In addition to the KG brand, KOG1 brand wire is also used, which is more flexible than the first option. It is used in cases where the welder needs to constantly move to perform work.

Connecting the welding cable is carried out taking into account certain rules:

1. Connections should be made using pressed or soldered lugs.
2. The cable is connected to the power connectors of the unit (+) and to the electrode holder in reverse polarity (-). The polarity can only be changed when the current parameters are changed.
3. When carrying out welding work, the welder is prohibited from pulling the inverter towards himself with wires.
4. Under no circumstances should the rated power of the cable be exceeded.

Connecting welding inverters using extension cords

Carrying out welding work is often associated with the remote location of the welded structure from the power source. Sometimes in such cases it is necessary to use an extension cord. An extension cord for an inverter is a conductor that has some resistance, which causes a voltage drop in the electrical circuit, that is, the longer the extension cord, the greater the operating voltage drop across it.

If the current is insufficient, the parameters of the welding arc may change and it becomes much more difficult to control. To achieve the required current at the end of the welding cable, you have to set an increased current on the inverter itself, which negatively affects its operation and can lead to failure of the device. Therefore, it will be easier to bring the welding device to the welding site than to buy a new one.

If the situation is hopeless, when choosing an extension cord, you need to be guided by the fact that a cross-section of 2.5 mm2 with a cable length of 20 m when using a device with an operating current of 150 A will be sufficient for normal operation of the welding machine. This length is quite enough for welding at home.

When using a carrier, you should follow some rules:

1. It is forbidden to wind an extension cord onto a reel, since the coiled cable is inductive, which can cause it to overheat and fail.
2. When welding with an extension cord, you need to control the change in mains voltage.
3. Heating of the extension cord is allowed up to a temperature of 70°C.

If you follow all the rules and recommendations when connecting a welding inverter, you will be able to carry out high-quality welding without negative consequences for the device itself.

Source: https://moyakovka.ru/instrumenty/podklyuchenie-svarochnogo-invertora.html

Diagram and malfunctions of Resanta Sai 190: principle of operation and search methods, repair and maintenance of the inverter

The welding inverter type resanta SAI 190, like all others, has significant advantages compared to a conventional welding machine. Thanks to the mobility and small weight of the resant, ordinary welding units have been forced out of the market. There are cases of inverter failure, and for this you need to know the principle of operation, structural diagram and malfunctions of the Resanta Sai 190.

Inverter type welder

Old transformer modifications of the welding machine have a very low price, high repairability, but have significant disadvantages: dimensions, significant weight and dependence on the mains voltage.

The output current of the electronic meter is limited by electricity consumption to 4.5 kW.

For welding work when using thick metals, current consumption increases, and this process places a significant load on old power lines, which also contain strands (after all, in the former CIS countries they are rarely replaced with new ones).

They have been replaced by inverter-type welding machines, the operating features of which are significantly different.

Features of operation

The scope of application is varied, ranging from households to enterprises. The main task is to ensure stable combustion and maintenance of the welding arc when performing welding work, thanks to the use of high frequency current. The operation of the welding inverter is based on the principles:

1. Conversion of alternating input voltage 220 V to direct (direct current is converted into high-frequency alternating current of a non-sinusoidal nature).
2. Subsequent rectification of the high-frequency current (frequency is maintained).

Thanks to these principles, there is a significant reduction in the weight and dimensions of the inverter, which makes it possible to additionally integrate cooling.

Operating principle and main characteristics

To troubleshoot inverter welding machines, you need to familiarize yourself with its block diagram. It consists of the following elements:

1. Rectifier.
2. Inverter.
3. Transformer.
4. High frequency rectifier.
5. Control and stabilization circuit (driver and control board).
6. Welding current regulator.

Thanks to this device, weight and dimensions are reduced. The use of a pulse transformer allows you to obtain powerful currents in the secondary winding. Consequently, the welding inverter is an ordinary switching power supply, like in a computer, but with quite a lot of power. As the frequency increases, the mass and dimensions of the transformer decrease (inversely proportional). To obtain high frequencies, powerful key transistors are used.

Switching occurs with a frequency from 30 to 100 kHz (depending on the SAIPA model). Transistors only operate from direct voltage (U), converting it into high frequency current. The result is a direct current from the rectifier (rectification of the mains voltage 50 Hz).

In addition, the rectifier includes a capacitor filter. When current is passed through the diode bridge, the negative amplitudes of the alternating U are cut off (the diode passes current only in one direction).

Positive amplitudes are not constant and a constant U is obtained with noticeable ripples, which must be smoothed out using a large capacitor.

As a result of the transformations, a DC voltage of over 220 V appears at the filter output. The diode bridge and filter form the inverter power supply. The transistors are connected to a step-down pulse high-frequency transformer, the operating frequencies of which range from 30 to 100 kHz (30000.100000 Hz), exceeding the mains frequency by 600 or 2000 times. As a result, there is a noticeable reduction in weight and dimensions.

The most common models are the resanta SAI 220 (220a, 220k), as well as the 190 (190a) model. Welding inverters have similar characteristics, differing in welding current:

1. Mains voltage ranges: 145.270 V.
2. Maximum current: up to 35 A.
3. No-load voltage: 75.85 V.
4. Arc forming voltage: 22.30 V.
5. Welding current ranges: 5.270 A.
6. Load duration (maximum current): 4.8 min.
7. Maximum diameter (d) of electrode: 5 mm.
8. Weight: about 5 kg.

Scheme and repair

If you don’t want to send the welder in for repairs and want to figure it out yourself (after all, the diagram is not that complicated), then you need to find and study the diagram and faults of the RESANTA SAI 190. If you have experience, then you don’t have to use the diagram at all, which is only needed for convenience and quick search malfunctions. To illustrate the example, a diagram of an inverter-type welder RESANTA SAI 220 (190) is shown, and the main radio elements that often fail are noted.

Scheme 1 - Electrical diagram of the welding inverter Resant SAI 220.

To repair the device, you need to understand typical faults and how to eliminate them.

Typical faults

Sometimes an inverter-type welding machine malfunctions. The causes and consequences can be varied. If possible, you should take it in for repairs. However, many will want to do it themselves. Thanks to this solution to the issue, you can increase your knowledge in the field of electrical engineering, because there are a lot of electrical devices and you can significantly save on their repair. Faults should be classified into simple and complex. Simple ones include:

1. Overheating due to dust.
2. Broken wires.
3. Loss of power (due to wet housing).
4. Punching the mass onto the body.
5. Bad contacts.
6. Electrode sticking.

Any electrical device does not like dust, since it impedes the transfer of heat and is a conductor of current (possibly a short circuit). Even with high-quality cleaning of the room, there will still be dust. Regular maintenance can not only extend the life of the devices, but also protect you from many financial and repair problems.

Wire breaks occur in places that are subject to constant bending. Kinking wires are very difficult to track and often lead to short circuits. In addition, the contacts on the pads holding the electrode become loose, making welding of lower quality or impossible. Periodically, all contacts need to be tightened.

Working in wet conditions also affects the welder's performance. Power loss may occur. In this case, such operating conditions must be avoided.

When the mass penetrates the housing (knocks out the fuse and the meter), you need to check the places of contact of the live parts with the housing and insulate the wire.

Electrode sticking occurs if you use a long extension cord with a small cross-section or when the mains voltage is low.

In addition, if the arc is unstable, you should check the quality of the electrodes and the set current.

Complex type breakdowns

Complex type failures include malfunctions of any radio element and require additional knowledge. If you have no experience in repairing radio equipment, then there are 2 ways to solve the problem:

1. Give it to a qualified specialist.
2. Gain experience in this area and do everything yourself.

You should pay attention to safety rules when repairing equipment and be very careful. In fact, there is nothing difficult about repairing on your own. You just need to open the Internet and find all the parts for an inverter-type welder. There is a lot of information on the Internet about checking a specific part. There is even testing of microcircuits at home.

First of all, you need to visually inspect the parts. These could be burnt resistors, diodes, swollen electrolytic capacitors, a burnt transformer and much more. If nothing is detected, then you need to check the input U to the diode bridge. To do this, its output must be disconnected. If the diodes are broken, you need to replace the faulty ones and try again. If the LEDs do not light up, then you need to check them and, if possible, replace them with serviceable ones.

The next step is to check the fqp4n90c transistor. The 4n90c key transistor in the power supplies of welding inverters is used to increase the frequency of direct current and transmit it to a pulse transformer. An analogue of fqp4n90c (what to replace) is STP3HNK90Z, but it is advisable to find the same one.

If the power unit malfunctions, you need to check the transistors (a visual check may not show anything). To do this, you need to unsolder them and check them with a tester (checking methods can be found on the Internet). A driver made with transistors or microcircuits fails in the same way. It is checked by desoldering and checking each element separately.

Replacement of faulty parts is carried out with their analogues or elements whose characteristics exceed the parameters of the original parts.

For repairs, a multimeter and an oscilloscope are needed (measuring signal parameters on the control board). If the control board is faulty, the yellow LED lights up. This indicates an unpreparedness for welding. In this case, you need to disassemble the inverter and measure the voltage at the connectors of the control board (hereinafter referred to as CP). During measurements, the data should be compared with the table values ​​(Table 1) of a working control unit.

Table 1 - Comparison of U indicators.

If the measurements differ from the table values, then you need to unsolder the control unit, find the UC3845B (UC3842) microcircuit and measure its operating modes.

Table 2 - Operating modes of the UC3845B (UC3842) chip.

No power is supplied to the 2nd leg due to a faulty resistor R013. It is necessary to carefully unsolder it and check it, the resistance should be about 1.21 Ohms. If it is faulty, then you need to replace it with the same one or take a higher power (initial power 0.25 W).

The 3rd leg of the microcircuit does not receive power due to faulty R011 (47 at 0.25 W), it also needs to be checked. Legs 3 and 6 are connected and, therefore, when replacing the resistance, U and 6 will appear. If this does not happen, then you need to check the fqp4n90c transistor.

Next, you need to restore power to the 8th leg (resanta sai 190 or 220), it is connected to a chain of elements. Weak points in it that need to be unsoldered and checked: diode D011 and R010.

After all this, you need to measure U. If it matches the table values, you should connect everything and test it. When fully restored, the inverter will turn on and the yellow LED will not light up. After a positive test run, you can assemble it completely.

One of the weak points is the power supply. Signs of a malfunction: the green LED lights up, and then the yellow LED lights up, the relay is activated and the fan starts, and after about 2-3 seconds the device turns off.

The main reason: the driver, or to be more precise, it is necessary to ring the transistors that are located in winding II of the galvanic isolation transformer. You also need to carefully inspect the power supply board for burns and faulty electrolytic capacitors.

If faulty parts are found, they must be replaced with elements of the same type or their analogues.

The transformer may fail, and this phenomenon is quite rare. It is necessary to test the windings for short circuits and current leakage to the housing.

Thus, troubleshooting common welding inverters is quite simple. The operating principle of each model is the same, and they differ only in details and design. When making repairs, it is very important to follow safety regulations when repairing radio equipment.

The initial stage of repairing a welding inverter (this rule applies to any equipment) is to conduct a visual inspection of all elements for broken contacts, burning and swelling of elements, as well as poor contact (all contacts must be thoroughly cleaned before starting repairs).

Source: https://chebo.biz/stroyka-i-remont/shema-neispravnosti-i-remont-resanta-sai-190-svoimi-rukami.html

company's news

13.02.2016

Good afternoon, dear visitors of the Professional store website.

In this review we will provide you with information about the Resanta SAI 250 inverter-type device.

The country of manufacture of this device is China, and the brand is Latvia.

Model SAI250 is a universal solution that combines power (250 Amperes), size and cost.

Of Resant's wide range of welding equipment, this device is in a place of honor - in the middle.

 About the Resanta brand

This company initially specialized in the production of voltage stabilizers. The country of origin of this product is Latvia.

Warranty 1 year (12 months).

Where is Resanta welding equipment manufactured?

The country of production of Resanta welding inverters is the People's Republic of China.

Country of origin is Latvia.

A little about Resanta welding inverters

The Resanta brand has several lines of welding inverters. As of today (03/26/2014) there are only 3 of them:

COMPACT version - operates from 220V +- 10%, has small dimensions: SAI 160K, SAI 190K, SAI 220K, SAI 250K (link to news about them);

Regular version - operates from 220V +- 10%: SAI 140, SAI 160, SAI 190, SAI 220, SAI 250 Professional (from 160V);

Reduced voltage version - operates from 140V: SAI 160PN, SAI 190PN, SAI 220PN, SAI 250PN;

PROF version - operates from 100V: SAI 190PROF, SAI 250PROF.

We specifically highlight this device, since it is more universal among all Resanta inverters.
From now on we will talk only about SAI 250.

The SAI250 Resanta inverter complies with GOST standards: GOST 12.2.007.8-75, GOST 51526-99.

The Resanta SAI250A inverter has an iron case.

The ground (insert from the cable with the grounding terminal) must be connected to the lower socket with the “+” sign.

The insert with cable and holder must be inserted into the socket with the “-” sign.

This is the case when welding carbon steels, that is, ordinary metal. If you need to cook cast iron or non-ferrous metals, this already requires changing the polarity, that is, swapping the mass and holders.

The SAI250A device is equipped with a strap so that it can be hung on the shoulder. In the photo you can see a fan behind the grille that cools the device.

The serial number on the device (near the “ON/OFF” machine) must match the serial number on the warranty card (see photo below).

This is what the warranty card for any Resant welding inverter looks like.

As you can see, the serial number on the inverter body matches the warranty card (SH49.250.17811).

If the sticker on the inverter body is damaged, the service center may remove the inverter from warranty. This sticker is intended to prevent the buyer from disassembling the welding machine on his own.

This is what the SAI250 inverter passport looks like. The passport contains the technical characteristics of all devices and the product warranty card.

Delivery set of welding machine Resanta SAI250

Here is the entire list of delivery kits for Resant SAI 250A:

1. Inverter SAI250;
2. Electrode holder with 1.5 meter cable;
3. Ground terminal with cable;
4. Product data sheet SAI250.

Technical characteristics of SAI 250

Operating voltage range: 220V +10% -30%;

Maximum electrode diameter: 6 mm;

Welding current control range: 10-250 A;

Arc voltage: 29 V;

Open circuit voltage: 80 V;

Maximum current consumption: 35 A;

Load duration (LO): 70%;

Protection class: IP21;

Weight: 5 kg;

Operating temperature range: from -10 to +40 C.

Anti-stick - anti-sticking (Anti-stick)

This function ensures that the electrode being welded is separated from the metal surface during welding. in simple words, when welding with a short arc, the electrodes do not stick to the metal.

Arc force

Allows you to boil metal without leaving burns.

Hot-star - hot start (Hot-star)

The ability of this device to ignite the electrode when welding begins. The inverter automatically ignites the arc during MMA welding.

Load period 70%

PV 70% - off period, or PN - loading duration - this is an indicator that corresponds to the operating time of the welding machine with a continuous arc. The entire period of operation is 100%, if PN (PV) is 70%, then the inverter can operate 7 minutes out of 10 continuously. After 7 minutes, the device may turn off, and the yellow light on the front side of the inverter will light up.

Possibility of operation at reduced voltage

SAI 250A Operates from 160 V. If the voltage in your outlet does not reach 220 V, or vice versa, exceeds this value, this inverter will work.

Disadvantages of the SAI 250 inverter

On the holder you can see letters and numbers: KV-200. It is unknown what exactly this marking means. At first glance, it may seem that this is a designation of the welding current value of 200 Amps, for which this electrode holder is designed.

The electric holder cable with the SKR insert is designed for operation from -10 degrees to +40. If the temperature is below -10, the cable may burst when bent. Perhaps a simple Russian cable KG-16, KG-25 would be better.

The length of the welding cable is just over 2.0 meters (including the electric holder).

The ground cable is of the same quality as the one for the electrode holder.

The welding cable for ground is 50 cm shorter than the cable for the holder (this is how it should be).

The length of the welding cable with ground (and with insert) is 1.5 meters.

What electrodes to use for SAI250

This inverter is an inverter-type welding machine that operates on direct current. You can use electrodes that weld with direct current (constant), or direct and alternating current (variable).

We recommend electrodes from the Losinoostrovsky Electrode Plant (LEZ) marked MP-3C (blue).

These electrodes are a little more expensive than Chinese ones, but they hold the arc perfectly.

There are also electrodes with a diameter of 3 mm.

We hope this review was useful to you, dear visitor to our site.

Source: http://tuzhilkin.kz/news/obzor-resanta-sai-250

Resanta SAI 160: description and advantages, operating procedure

Compact household welding inverters, which are intended for a small production workshop or work in a garage and at a summer cottage, are very popular today. Until the recent past, such devices operated on transformers and were characterized by bulky dimensions and difficulty in operation, but the advent of simple inverters allowed every homeowner to easily carry out welding, while the cost of such equipment is very affordable.

The Resanta company is a large manufacturer of electrical equipment, whose products combine affordable prices and excellent quality. The inexpensive welding machine Resanta SAI 160 for household use is very popular on the domestic market; it is small in size and easy to use.

Thanks to the use of an inverter circuit, even with its low power, it provides maximum welding quality and allows you to work with various refractory metals.

In the line of this model you can find several modifications that differ in the scope of use.

• The basic SAI 160 is a universal-use equipment that belongs to the household class.
• Resanta 160K is a Compact series, which is made in a small case and weighs about 3.5 kilograms.
• Resanta SAI 160 PN is intended for use in an electrical network with a voltage of 140−160 W, that is, suitable for use in garages and summer cottages.

The basic model SAI 160 has proven itself to be extremely reliable and durable equipment. It allows you to weld even refractory metals or thick products, the high-quality welding of which requires a powerful current. The advantage of this model is its cost, which does not exceed 8 thousand rubles.

Device characteristics

Resanta SAI 160 is designed to work with welding current in the range of 10–160 amperes. The maximum power will be sufficient for welding cast iron and other refractory metals.

The diameter of the electrodes used is 1.5−4 millimeters. The choice of certain electrodes will depend both on the thickness of the products being welded and on their refractoriness indicators.

Automation SAI 160 provides significant simplification of welding work . There is a Hot Start function, which simplifies putting the equipment into operation, as well as an anti-stick option, which prevents damage to the electrodes if welding is carried out carelessly.

The weight of the basic model SAI 160 is 4.5 kilograms. This device is made in a durable metal case with powder coating, so the metal is perfectly protected from corrosion. However, it is still not recommended to use such inverters in rooms with high humidity.

The welding inverter Resanta SAI 160 is designed to work with a 220-volt power supply. Ten percent increases and decreases in voltage are allowed. But if there are significant surges and drops in voltage in the electrical network, which is typical for summer cottages and garage cooperatives, then we recommend that you still purchase the 160 PN model, which is specifically designed to operate at low voltage in the electrical network.

This model of welding inverter has a protection class of IP 21, so the device is grounded through the power cord. This ensures safe operation of the device. At the same time, we note that it is not recommended to use such a welding inverter in the rain outdoors or in rooms with high humidity.

The Resanta 160 welding machine is equipped with a forced cooling system using larger fans. On the body of the device there are numerous slots through which fans suck in the air necessary to cool the electrical and power parts. Remember that blocking such ventilation openings and working with the welding machine in a protective casing is prohibited, which can lead to rapid overheating of the device .

Inverter advantages

Among the advantages of this model, we note the following:

• Excellent welding quality.
• Compact dimensions.
• Ease of use of the device.
• Equipment functionality.
• Affordable price.

One of the undoubted advantages of SAI 160 welding inverters is the ease of working with them. No prior preparation or training in welding is required; you can understand all the features of using this device in literally 5-10 minutes. It is possible to perform manual or fully automatic welding.

On the front panel you can find an electric current regulator, which should be set depending on the thickness of the electrodes used for welding and the refractoriness of the working metals.

The presence of a wide range of adjustment of operating parameters allows not only to improve the quality of welding, but also gives the opportunity to work with a welding inverter for people who have never previously engaged in such work.

The inverter is equipped with appropriate overheating protection, which helps prevent device failure due to overvoltage and overheating. The automation constantly monitors the temperature of the unit and, when peak values ​​are reached, automatically turns off the inverter until the device has completely cooled down. The same thing happens when the voltage in the network increases or decreases, when the built-in relay turns off the inverter until the required characteristics of the electric current in the supply network are restored.

The undoubted advantage of using inverter technology for welding machines is a significant reduction in the size of such equipment, as well as improved welding quality . The latter is achieved by stabilizing the output voltage; accordingly, the welding arc will have the necessary power indicators, which eliminates the presence of undercooked sections of metal where the quality of the connection may leave much to be desired.

Like most household models of welding inverters, the automation and power part of the Resanta SAI 160 is extremely critical to the temperature and humidity of the surrounding air. All work can be carried out indoors or outdoors at temperatures from +10 to +40 degrees. You can learn more about the operating requirements for this unit in the instructions for this inverter model.

To simplify work, the front panel of the device contains appropriate terminals for connecting power wires and a welding cable. Such terminals and clamps provide high-quality fastening of wires and cables, which guarantees complete safety of using the device .

Before turning on the machine, it is necessary to set the minimum value of the welding current, after which the power switch is switched to the On position, the automation will light the arc, only after that the required value of the welding current is set on the machine.

Turning off the device is performed in the reverse order, that is, the current regulator is set to the minimum value, after which the power switch is switched to Off mode.

Important. By adhering to this algorithm for turning off and turning on the equipment, you can ensure trouble-free and durable use of it .

The Resanta SAI 160 inverter welding machine is an inexpensive entry-level model that will be an excellent choice for summer residents and ordinary homeowners. Using the equipment is not particularly difficult, so anyone, even without experience in welding, can easily use such equipment, ensuring a high-quality connection of metal parts. This device is reliable, easy to use and is offered at affordable prices.

Source: https://tokar.guru/svarka/resanta-sai-160-nedorogoy-svarochnyy-invertor-nachalnogo-urovnya.html

How to operate a resanta welding machine

You bought a welding machine and want to learn how to weld with an inverter for beginners.

There is no need to be afraid of difficulties! The inverter machine is easy to use; anyone without experience or knowledge can master the welding process in a short time.

Equipment, equipment, safety precautions

Safety precautions. Welding production is associated with electrical voltage, or in common parlance - current. The current is invisible, but can kill a person.

We check the welding cables for serviceability and connect them to the inverter equipment. Return cable with a clothespin on metal to the negative connector. Cable with electrode holder to connector +. We insert the electrode into the electrode holder.

When connecting the device to the network, visually evaluate the current-carrying cables for serviceability. After making sure that the cables are in good condition, we plug in the plug into the socket and the toggle switch on the device, having previously set the current regulator to the lowest value. If the cooling fan starts working smoothly, without crackling or noise, then everything is fine.

Metal weight. When connecting heavy structures, take precautions. If multi-ton products collapse, they can lead to death or disability.

Equipment. Welding production involves high temperatures. The welder must have:

• canvas mittens (gaiters);
• robe (special suit);
• mask with a light filter;
• respirator for work in confined spaces;
• boots with rubber soles.

Gaiters are used when welding at heights, when arms are raised up, and mittens in other cases.

• welding machine;
• hammer;
• brush;
• electrodes.

Electrodes are selected according to the metal (carbon content, additives) and diameter, depending on the thickness of the metal and the technical characteristics of the inverter.

Inverter Welding Basics

For beginners, experienced welders advise attaching the holder cable to the body, pressing it with the elbow of the arm and wrapping it along the forearm (from the elbow to the hand), and taking the holder in your hand. This way the shoulder joint will pull the cable, and the arm and hand will remain free.

The method will help you manipulate your hand with ease.

Correct placement of the cable on the forearm. You should not work with bare hands.

If you simply take the holder in your hand without wrapping the cable around your forearm, then during the welding process your hand will get tired and wrist movements will cause the cable to dangle. Which will affect the quality of the welded joint.

How to cook using inverter welding correctly? We set the welding current on the machine according to the diameter of the electrode, the type of connection and the welding position. Setup instructions are available on the device and the electrode pack. We take a stable stance, move our elbow away from the body (no pressing), put on a mask and begin the process.

For beginners, it is better to start welding with an inverter with metal workpieces larger than 20 cm.

It is known that a beginner, putting on a mask and lighting an arc, stops breathing, trying to boil the entire length of the workpiece in one breath. With short products, you will develop the habit of cooking in one go. Therefore, practice on long workpieces, learning to breathe properly when welding.

Workpieces (plates) on the work table can be placed in a horizontal plane - vertically towards you or horizontally, it makes no difference.

At the beginning of welding, place the electrode clamped in the holder at an angle of 90 degrees (perpendicular) and move it towards the seam by 30-45 degrees. Light the arc and start moving.

1. If welding is performed at an angle backwards, then the tilt of 30-45 degrees goes towards the seam.
2. If the connection occurs at an angle forward, then the electrode is tilted away from the seam.

The distance between the surface to be welded and the electrode is 2-3 mm, imagine that you are running a pencil along a sheet of paper.

Please note that when welding, the electrode decreases as it burns - gradually bring the melting rod closer to the surface at a distance of 2-3 mm and maintain an inclination angle of 30-45 degrees.

Watch a useful video on how to learn how to weld with electric welding for beginners:

How can a beginner learn to weld with a welding inverter?

First we learn to light and hold an arc. Feel the edge when to bring the electrode closer to the surface to be welded during combustion so that the arc does not interrupt.

The electrode is ignited in two ways:

The new electrode ignites easily. A slag film appears on the working rod, preventing ignition. You just need to tap longer to break the film.

1. To facilitate arc ignition, inverter devices have a built-in Hot Start function.
2. If a beginner quickly brings the electrode closer to the surface, the Arc Force function (arc force, anti-sticking) is activated, increasing the welding current, preventing the electrode from sticking.
3. If the melting rod gets stuck, the Anti Stick function cuts off the current, preventing the inverter from overheating.

What is arc force on a welding inverter and how to use it.

It is better for a beginner to first learn on a thread seam; the electrode is held smoothly, without oscillatory movements.

After mastering thread technology, proceed to welding metal with oscillatory movements. Which are used on thick metal for heating, holding the electrode at a certain point using movements - herringbone, zigzags, spiral or your own method.

Types of oscillatory movements

At the beginning of the connection, we carry out several movements from left to right, forming a weld pool and go along the seam making oscillatory movements. The angle of inclination of the electrode is 30-45 degrees. After passing, we beat off the slag with a hammer and clean it with a brush. Take care of your eyes, wear glasses.

Tip: at the end of the weld, make oscillatory movements to the sides and move the electrode towards the deposited metal. This trick will add beauty to the welded joint (get rid of the crater).

how to weld corner joints, butt joints and overlap joints.

• single-pass (one pass replenishes the thickness of the metal);
• multi-pass.

A single-pass weld is performed on metals up to 3 mm. Multi-pass seams are applied for large metal thicknesses.

Welders check the quality of the seam with a hammer - they strike next to the seam. If the seam is smooth, without irregularities, then after the impact the slag flies off completely, there is nothing for it to catch on. It is important to select the correct temperature regime: an overheated seam (hot) will break, an underheated one - there is a risk of lack of penetration.

The current is selected based on the diameter of the electrode, in theory 30 A per 1 mm of electrode diameter.

Direct and reverse polarity when welding with an inverter

Let's consider polarity when welding with an inverter. With a DC connection, the movement of electrons is constant, which reduces spattering of molten metal. The seam is of high quality and neat.

The device has a choice of polarity. What is polarity is the direction of movement of electrons depending on the connection of cables to equipment connectors.

1. Reverse polarity when welding with an inverter - minus on the workpiece, plus on the electrode. The current flows from minus to plus (from the workpiece to the electrode). The electrode heats up more. Used for welding thin metals, the risk of burn-through is reduced.
2. Straight polarity - minus on the electrode, plus on the workpiece. Current moves from the electrode to the workpiece. The metal heats up more than the electrode. Used for welding thick metals from 3 mm and cutting with an inverter.

Source: https://crast.ru/instrumenty/kak-rabotat-svarochnym-apparatom-resanta

Resanta 190 sai: description of the welding machine, advantages and disadvantages, recommendations for use - Machine

Reading time: 3 minutes

Resanta SAI 190 is a welding machine from the SAI inverter line, designed for manual arc welding. This model is far from the most budget-friendly of the entire line, but it is not suitable for professional inverter welding. In our opinion, SAI 190 is an inverter for a student welder or a country craftsman.

From this article you will learn everything about SAI 190: technical characteristics, advantages and disadvantages, modifications of this model. And below there is a detailed diagram of the Resanta SAI 190 welding inverter, and more than one.

Characteristics and Features

The inverter welding machine SAI model 190 can be used in conjunction with electrodes with a diameter of up to 5 mm. The maximum welding current that can be squeezed out of this device is 190 Amperes. At least according to the manufacturer???? But practice has shown that achieving such values ​​is almost impossible. The current strength will always be slightly lower than declared.

The welding inverter model SAI 190 has compact dimensions and weighs no more than 5 kg. So you won't have problems transporting it. Summer residents can safely take the device to their apartment for the winter without worrying about its safety. You can cook at temperatures from -10 degrees to +40, which is extremely convenient.

The equipment is modest. The price includes the machine and two welding cables, plus a power cable. All other components must be purchased separately. But you will have access to a 2-year warranty.

Advantages and disadvantages

The first obvious advantage of the Resanta model SAI 190 is its ease of connection. Insert the plug into a household outlet and you can get to work. The main thing is that the voltage in the network is sufficiently stable and is not less than 200V.

The second plus is the “filling” of this inverter. It is designed based on IGBT type transistors. It is thanks to IGBT transistors that the manufacturer managed to make such a compact and lightweight device, which at the same time has additional functionality.

 Resanta welding machine: models for beginners

By the way, about functionality. This inverter welder is protected from overheating and has anti stick (also known as anti-stick) and hot start functions. Your welding work will not only be safe, but also simple.

To use the SAI 190 device you do not need to know the principles of electrical engineering. All controls and buttons are intuitive and labeled in large letters. You will see them even with poor eyesight. Therefore, such an inverter can be given as a gift to an elderly relative or friend who has long wanted to replace the bulky transformer with something more modern.

Now about the cons. The Resanta brand is Latvian, but the production is still Chinese. Two features emerge from this. On the one hand, thanks to Chinese production, the manufacturer was able to set a fairly low price for this model.

On the other hand, not each of us is ready to trust the notorious Chinese quality. Decide for yourself: is Chinese production an advantage or a disadvantage? And share your opinion in x. The second disadvantage is the technical characteristics.

Let's face it, for this price some Chinese brands make inverters that are more powerful and more interesting. Here we overpay for the brand and service.

With such a welder you will not be able to perform professional welding work, and sooner or later you will have to buy something more expensive and more functional.

Circuit and faults

Below we have attached several images with SAI 190 diagrams. Open them in new tabs to view them in full resolution.

And this is a list of the most common malfunctions that occur during operation of the SAI 190. They can be corrected on their own. If more serious damage occurs, we recommend contacting a service center.

Instead of a conclusion

The welding machine model SAI 190 is a good choice for your money. It is suitable for a welding student or an unpretentious summer resident who needs to repair or make something a couple of times a year. The manufacturer also produces various modifications of this model.

Among them are the Resanta SAI 190K inverter welding machine with reduced weight and dimensions for more convenient transportation, the Resanta SAI 190 PN, which operates at reduced voltage in your household electrical network, and SAI 190 PROF for practicing welders.

Choose any one to suit your taste and budget.

Do you want to know which electrodes are best for the Resanta 190 inverter from the SAI line? Read our articles in the “Electrodes” section. We wish you good luck in your work!

Source: https://regionvtormet.ru/instrumenty/resanta-190-sai-opisanie-svarochnogo-apparata-preimushhestva-i-nedostatki-rekomendatsii-po-ispolzovaniyu.html

Feeding device for the inverter, and how to feed wire into the welding zone

Just 15-20 years ago, working as a welder was labor-intensive and difficult. Welders used large and inconvenient transformers weighing more than 80 kg for their work. The device was equipped with special transportation loops for more convenient movement around the workshop or to the place of welding work. During transportation, special platforms were used. When working at height, it was necessary to feed them with a truck crane. This made the work of the welder and the people around him more difficult.

Inverter

But progress does not stand still and now there are compact inverter welding machines the size of a small box and weighing up to 15 kg.

The inverter device works on the principle of rectifying and converting the input network voltage, using special resistors, into a current with a large switching amplitude, then it is reduced to the operating current.

The main advantage is that efficiency is achieved up to 90% with small sizes and low weight up to 15 kg. There is also a smooth current setting , which is typical for welding thin metal.

Inverter machines can work both for welding with simple electrodes (MMA) and, together with a feed mechanism, act as a source for semi-automatic welding (MIG).

Nowadays, most inverters support welding modes such as coated electrodes (MMA), refractory tungsten electrodes in argon (TIG), and semi-automatic welding (MAG). They have a welding switch on the control panel , which selects a specific welding method.

Let's take a closer look at what a feed mechanism is and the advantages over welding with simple electrodes.

Feeding mechanism is a set of electromechanical devices that ensure automatic and uninterrupted supply of welding wire and shielding gas to the welding zone.

Feeder

Let's take a closer look at what the feeding mechanism consists of:

1. Welding sleeve. It is a flexible frame hose covered with multilayer rubber to protect and insulate the power cable. Inside there is a special steel spiral channel for feeding the welding wire to the welding site. The hose also to protect the weld pool from the environment. Near the welding torch there is a button to turn on the wire and gas feed mechanism.
2. Wire feed mechanism. Ensures uninterrupted wire feed through the welding hose. It consists of a direct or alternating current electric motor, a clamping device for pressing the rollers using screw clamps with a certain force.
3. Device for installing a cassette with welding wire. It is located near the feed mechanism and is designed to provide the welding arc with filler material for a long time. The cassette can be positioned both vertically and horizontally relative to the feeding mechanism. The cassette is secured using a special nut or clamps.
4. Control unit. It is used to adjust the wire feed. The adjustment can be electronic using a rheostat or more coarse thanks to interchangeable gears. Modern ones are equipped with digital displays, on which you can accurately set the welding speed and thereby ensure better seam formation.

The main advantages over welding with electrodes are a faster welding process, there is no need to change the electrode often, and better control over the welding process. The disadvantages are the fear of drafts and strong winds (possible formation of pores), and the connection to the source of protective gas (cylinder, ramp).

How to connect the feeder to the inverter?

To connect the feeder you will need:

• screwdriver figured;
• soldering iron with a power of 50 watts;
• rosin;
• solder;
• drill with a drill bit for drilling out rivets;
• pliers.

Before starting the operation, make sure that the device is not connected to the network!

So, after making sure that the inverter is de-energized, remove the protective cover. To do this, take a shaped screwdriver and unscrew 4 screws on each side on the side walls. Next, take a drill with a small drill and drill out the rivets that secure the plug to the back wall of the device.

After removing the plug, feed wires with a three-pin connector through this hole and turn on the soldering iron.

While it is heating up, carefully peel off the protective layer of varnish from the capacitor located in the middle along the board, as well as from the track in the middle and from the metal hole.

After everything is done, solder the wires securely and carefully according to the instructions included with the device. Next, we take rivets and pliers and secure the 3-pin socket with wires that are soldered to the back wall of the case. When everything is done, put the cover back in place and screw the screws back on.

Don’t forget to get a cylinder with protective gas, a reducer for adjusting the gas supply, 10-15 meters of hoses for connecting the reducer and the device, and a coil of welding wire. That's all, all you have to do is connect everything and your semi-automatic welding is ready.

Source: https://stanok.guru/oborudovanie/akkumulyatory-i-bloki-pitaniya/ustroystvo-podayuschego-mehanizma-dlya-invertora.html

What kind of cable is needed for the Resanta Sai 220pn welding machine? — Website about

page » Articles about welding » Welding station » Equipment » Cable » Welding cable for inverter

Inverters are easy to use, compact, mobile, easy to connect, affordable, and suitable for beginners and experienced professionals. The popularity of this equipment requires the correct choice of cable for it. The article will discuss which cable is best to use for an inverter welding machine.

Welding cable design

The cable design includes the following elements :

• conductive copper core consists of many wires, the cross-section of which does not exceed 0.2 mm;
• covering can be made of rubber or rubber (natural or butadiene);
• The separating layer is made of a special transparent film that prevents the coating and core from sticking together.

Characteristics of welding cables

As noted earlier, the cable for the inverter must be highly flexible . In addition to this important property, electrical conductors are required to meet the following characteristics :

1.  Strength , i.e. resistance to mechanical stress: shocks and tears.
2. Resistance to temperature fluctuations, the ability to use the conductor in conditions of very low or fairly high temperatures.
3. Resistant to sunlight and moisture .
4. Immunity to mold and mildew .
5. Elasticity - minimal likelihood of bending.

There are few brands of conductors designed specifically for welding work. And there are only two types of cables that meet the above characteristics: KG and KOG.

Among craftsmen, the first type is in particular demand - flexible cable (KG). It should be used to connect mobile mechanisms to networks with alternating voltage up to 660 V with a frequency of 400 Hz . DC voltages up to 1000 V .

KOG is a particularly flexible cable, analogous to KG, indispensable when working in hard-to-reach places, ensures quick changes in the position of equipment and guarantees freedom of action for the performer.

It is recommended to use it for connecting electrode holders, automatic and semi-automatic installations to networks with alternating voltage up to 220 V with a frequency of 50 Hz or constant - up to 700 V.

If the performer is thinking about which brand of cable for the remote control of the welding inverter is more suitable, then you can choose KOG.

Each of these brands has the following varieties, which are clearly distinguishable if you look at the markings:

• KOG-HL/KG-HL - cold-resistant , resistant to extremely low temperatures, down to -60°C;
• KOG-T/KG-T - tropical , resistant to various types of mold formations, operating temperature should not exceed +55°C.

You should also pay special attention to the following varieties:

• KGn has non-flammable insulation and should be used in fire hazardous conditions.
• KOG-U is used only in temperate climates , in the temperature range from -45 to +40°C.

Many performers have equipment of specific brands or manufactured by specific factories. Welders are especially often concerned with the question of which welding cable to choose for the Resanta inverter? Both brands: KG and KOG would be a suitable choice in such a case.

Section selection

Choosing the right wire cross-section is the main task. The conductivity depends on the cross-section, which, in turn, has a direct impact on the speed of work and the quality of the formed connection. The cable must comply with the technical specifications of the inverter.

Conductors with a small cross-section (up to 7 mm2) will be a suitable option for small devices that operate from a household electrical network of 220 V.

Also for inverter-type units, cables with a cross-sectional area of ​​10 are suitable; 16 and 25 mm2. More detailed information about the characteristics of the KG and KOG conductors is provided in the linked articles.

Important! Use of unsuitable wire may result in overheating, fire and/or short circuit, which may cause equipment failure or fire.

When connecting conductors to the inverter, you must adhere to the following rules :

• connection is made using special lugs , insulation of connections is required;
• The cords should be connected to each other by crimping ;
• When connecting to connectors and electrode holders, polarity must be observed ;
• The cables the power of the existing device.

It is not always possible to perform crimping when connecting two pieces; some practitioners use the following method of splicing cables.

Is it possible to extend the welding cable on the inverter?

The length of the wire is selected based on the magnitude of the output current load and its losses along the length. The longer the cable, the higher the losses and the lower the current. In order to achieve balance, the performer has to set an increased voltage, which can lead to a change in the arc and equipment breakdown. Therefore, excessive extension of the inverter welding cables is not recommended.

On the other hand, it is worth familiarizing yourself with the experience of a practicing welder on YouTube.

Important! The suggestion to use a welding cable extension for an inverter should be treated with suspicion and skepticism.

However, it is worth noting that manufacturers do not set any restrictions on the extension of wires. A special connector for the welding cable to the inverter will help you make the connection efficiently, easily and quickly. More information about connectors of various types is presented in the article “Connector for welding cable”.

Consequently, each performer will be able to independently answer the question posed in the title.

Where to buy electrodes of various brands

Choose manufacturers and sellers of welding electrodes by clicking on the link below to the page of our catalog of companies.

Select a company

Source: https://orensbyt.ru/elektrika-v-kvartire/kakoj-nuzhen-kabel-dlya-svarochnogo-apparata-resanta-sai-220pn.html