Today, the market of the proposed welding machines has a huge selection of various models and brands of manufacturers. One of the brands presented, which should be given attention, is a modern welding machine with an inverter "Resanta SAI-220 PN".
Operating principle
The principle of operation of welding machines is that the interfacial voltage of 0.4 KV AC of a standard frequency of 50 Hz is converted to a constant voltage of 400 V, after which the inverter converts to high-frequency voltage, and it is again rectified by a diode bridge. Unlike a welding transformer with an ordinary rectifier, in a welding machine with an inverter, the standard alternating voltage passes not two stages, but three, but at the same time a constant operating voltage is 90% of the fullness versus 60% that is obtained from the welding machine. The welding machine "Resanta SAI-220 PN", through the use of high-quality semiconductor material, produces a constant voltage of even 95% of fullness. That is, it makes it possible to keep a uniform welding arc much more stable than other welding machines.
Advantages of this welding machine
- The presence of a current regulator on the welding arc.
- Intensive forced cooling of the elements of the device through which a large current passes, which ensures continuous continuous operation.
- The presence of the “anti-sticking” function, which automatically reduces the operating current when the electrode sticks to the product during arc ignition. When the electrode detaches, the device restores the original, configured parameters.
- The presence of the “hot start” function, which improves the ignition of the arc by a short pulse of increased operating current parameters.
- Sustainable arc burning, which is not subject to those unexpected extinctions that were characteristic of welding transformers.
Professional welders who worked with the Resanta SAI-220 apparatus, focused their opinions on precisely these advantages of the apparatus. Workers also focus on the fact that inverters greatly facilitate the work of welders and make it better.
Device performance
Resanta SAI-220 devices have technical specifications that enable the welder to work in a fairly wide range of input and output voltages with stable maintenance of the working current on the arc. Good arc control is ensured by the fact that intensive cooling allows you to keep the arc with the given current for a long time.
- The input voltage on the device is from 140 V to 240 V.
- The maximum input current is 30 A.
- At idle, a voltage of 80 V is maintained.
- The voltage during arc burning is 28.8 V.
- The welding operating current is adjustable in the range from 10 A to 220 A.
- Long-term loading of the device is 154 A (70% of Imax).
- The diameter of the electrode that can be used in SAI-220 is from 1.6 mm to 6 mm.
- Protective safety class - IP21.
It is able to work stably and efficiently at ambient temperatures from -10 ° C to + 40 ° C. It is not allowed to work in the open air with precipitation.
External device
"Resanta" inverter "SAI-220" is a metal case, in front of which there is a panel. Here are the regulator of the magnitude of the operating current, the indication "Network", the indication "Overheating" and power current connectors for connecting DC cables. The welding machine has a forced cooling system. For this reason, it is strictly forbidden to block the ventilation holes in the housing.
The “overheat protection” system is triggered by a light bulb located on the panel. On the case near the connectors for DC working cables there are clear signs: "-" power terminal and "+" power terminal. There is a toggle switch off the network - "Network" and an indicator light - "Network". A belt is made on top for ease of transportation and operation of the apparatus.
The internal structure of the product
The welding inverter "Resanta SAI-220 PN" consists of the following main units:
- Power block of a transformer rectifier of standard and low voltage with a frequency of 50 Hz.
- An inverter power unit that converts DC voltage to high frequency AC voltage.
- A high-frequency power transformer that lowers the input voltage to the voltage necessary for safe operation of people.
- The power block of a high-frequency transistor rectifier, which rectifies a high-frequency current with a low voltage transformer.
- A stabilizing inductor, which serves to smooth the pulsation of the rectified and stabilized current of the working welding voltage.
All semiconductor devices are made on the basis of MOSFET or IGBT transistors. High properties of stable dynamics of arc burning are ensured by the use of semiconductor elements that are produced using the most modern technologies.
Device protection
The manufacturer made every effort to ensure that Resanta SAI-220 welding devices were safe to operate not only for professionals, but also for those who are involved in welding work from time to time.
The most important point in this problem is the insulation of the conductive parts of the device. Connection to standard equipment is carried out by a flexible cable with double insulation, which withstands voltage without breakdown up to 3000 V for 2 minutes.
The internal components of the welding machine are fixedly mounted on insulators, which were tested for breakdown in the manufacture of 1000 V for 3 hours. Dustiness of these insulators by metal dust and chips is not allowed. Moisture is not allowed to enter the device in order to avoid a phase short to ground, which will inevitably cause the device to fail.
The mechanical security of the AIS corresponds to IP21. That is, objects more than 12 mm thick cannot get inside the device.
The procedure for preparing the apparatus for work
Attention! The connection of the Resanta SAI-220 device (the reviews of the welders are indicated and the manufacturer's instructions say) should begin with the assembly of the low operating voltage circuit:
- Check the disconnected position of the "Network" switch.
- Connect the welding cables of the required section to the working power terminals: "-" and "+"; check that the electrode holder is connected securely to the cable required by the welding conditions.
- Reliably connect the second working power cable to the product with which work will be carried out.
- Attach the Resanta SAI housing to a stationary grounding device; if this is not the case, then to portable grounding in the form of a pin with a length of at least 140 cm, which is clogged into the ground at a distance of at least 5 m from the device.
- Connect the device to a standard voltage network; apply standard voltage to the device.
- Turn the "Network" switch to turn on the welding machine.
- By rotating the regulator of the value of the working direct current, set the required current mode of a specific operation.
- Check for shorted working power cables.
The modes that depend on the diameter of the electrode used, the operation of the inverter welding machine, are as follows:
- 1.6 mm - 20–45 A;
- 2.0 mm - 45–70 A;
- 2.5 mm - 65-85 A;
- 3.2 mm - 90–145 A;
- 4.0 mm - 130–195 A;
- 5.0 mm - 160–220 A;
- 6.0 mm - 210-300 A.
SAI Operation Safety
If we analyze the reviews of welders who have been working on it for Resanta SAI-220, we can conclude that this device is very safe and convenient to use. However, the following safety precautions should be observed:
- If there is no grounding through the power cord, then installing a portable grounding is a must.
- The place of welding should be well ventilated, because many toxic and harmful gases are generated during welding.
- The welder must work in a special welding suit to avoid burn injuries .
- To protect eyes and face, it is mandatory to use a welding shield or welder mask.
- Fire safety measures during welding should be carried out in full according to the standard instructions, from which the removal of points is not permissible.
Inverter welding machine in the Russian market
Inverter welding machines are increasingly becoming popular with consumers. Especially they have become popular among lay people due to their light weight (up to 6 kg), ease of use and ease of use. Prices are pretty affordable: from 150 to 250 $ per unit.
At Resanta SAI-220 PN, the price ranges from $ 210 to $ 240 for various modifications, the performance of which depends on the semiconductor elements and blocks used. Easy maintenance allows the AIS to gain a leading position among similar products.
The manufacturer constantly listens to the opinions of its customers and monitors the dynamics of not only sales, but also reviews of its products. To do this, a special website has been created on the Internet, where every interested and not indifferent person can leave feedback. These reviews are interesting not only to the manufacturer, but also to other consumers.
Operation of invertor welding machines
Basically, the Resanta SAI-220 welding machine reviews are the most positive and flattering. But there are those who say that when working on it in wet weather, it "plucks" with an electric current. It is useful to such consumers to remind once again that working with any electrical devices and devices is fraught with danger if basic safety rules are not followed. The device weighing only 5.5 kg during welding with an electrode with a diameter of 5 mm has a power of 15 kW, which is enough to throw a stone of 10 kg into the height of a three-story building. Therefore, there is no extra caution when working with energy-intensive equipment.
All safety precautions and safety measures that are described in the instructions for the device must be strictly observed. If there is no RCD and a three-core power supply system with a stationary grounding device, then it is mandatory to have a portable temporary grounding and use it.
Repair of invertor welding machines
Craftsmen are able to repair everything. And no one has anything against this hobby. But the repair of "Resanta SAI-220 PN" is far from an easy task. Its high technical characteristics are ensured due to the fact that all components of this welding machine are very precisely balanced. To it does not fit any inverter. No, if another inverter that allows the current at the low side output of about 220 A to pass through the device, the device will work, but the stability of the welding arc will decrease. This is unambiguous. The mismatch of the input and output resistances of the inverter to the rectifier block of the power current will significantly reduce its durability. And this is the case for each node.
If the AIS welding machine is out of order, it is best to contact a service center where the worn out components will be replaced with the original ones. It should be noted: if moisture and metal dust and chips are not allowed to enter the device, if long overheating of the units is not allowed, then the device will faithfully serve for decades.