Making a homemade welding inverter is easy, especially if you get along with electronics. The main thing is that you have free time (5-6 hours) and a desire to do this work. This unit is useful to all owners. Welding inverters are new modern welding machines that are now coming to the fore.
Device of the invertor welding machine.
There are many different types of inverters on the market. But the device, made by yourself, may turn out better and the inverter will be cheaper with its hands than buying a new device.
Some information about welding machines
Now it is very difficult to imagine any structure for which welding would not be required. Different voltages are used for this work. Depending on it, welding machines are divided into two groups: DC and AC. On a direct current it is allowed to cook by electric wire without coating and electrodes. In order to give a burning arc to small currents, it is imperative to have on the winding an increased open-circuit voltage of up to 70 V. A DC welding machine is better to use, it is used for thin-sheet metals, especially for automotive and roofing steel. The welding arc is stable at this stage, so the welding goes on both the direct and reverse polarity of the voltage that is supplied.
Classification of welding inverters.
What does a welding machine consist of? The main part of the welding device includes:
- transformer - the main part;
- primary and secondary coils;
- housing for welding machine;
- stationery or hank from a cash register;
- copper strip;
- copper tape.
How to make a homemade welding machine
The most important part in working on the inverter is the circuit. Begin manufacture of the welding device with a transformer assembly on which a copper strip of tin is wound (length 40 mm, thickness 0.3 mm). Still need a thermal interlayer, which is suitable as a stationery or hank from the cash register. It should be durable and not be torn when wound. Do not wrap with a thick wire, because This device will operate at high frequencies, which will lead to overheating of the transformer.
To avoid this, take a copper tape - this will be the second winding of three strips of copper. They will be separated by a fluoroplastic layer. For the second winding, take the paper again, as with the first one. True, the paper will darken, but it will not lose the properties of the color. Do not forget to put the fan in the transformer so that the winding does not heat up and cool. You can take a cooler from your computer at 220 V and 0.15 A. The diagram will help you understand the essence.
Wiring diagram of the welding inventory.
Then continue making the inverter on the basis of your scheme. The next step should be a cooling system that protects the welding machine from overheating. It is better to take it from the computer processor. A total of 6 such fans will be required, 3 of them should be directed towards the motor winding. Do not forget to install air intake in front of the coolers.
After that, you need to install a power oblique bridge. It will be located on two radiators. The top edge of the bridge will be on one side, and the bottom should be attached through a gasket on the other bridge. Diodes need to be brought out and placed towards the transistors. To reduce emissions, capacitors should be soldered to the board (14 pieces of 0.15 micron and 630 V each), they should be distributed to the entire power line.
In order for the splashes to intensify, and the losses of the IGBT become the smallest, it is worthwhile to insert snubbers with the capacitors C15 and C16 in the chain. IGBTs open more quickly, and the opposite process is longer. And at this moment C15 and C16 will begin to receive a charge through the diode that was installed. All this is done so that the snubber takes all the power and reduces the heat consumption by 4-5 times.Back to table of contents
How to connect a welding inverter do it yourself
Making this device is not as hard as setting it up. It will take longer. Will help serial connection:
Ways to connect a welding inverter.
- Connect the welding inverter to the mains. You will hear loud sounds, this unit will begin to transmit current. Electricity is supplied to the fan, making the welding machine quieter and its heating is reduced.
- Next, close the resistor. To do this, after charging the capacitors, you need to connect a relay. Current jumps when switching on decreases.
- Please note that it is impossible to connect the transformer without a resistor part, as an explosion may occur. To find out the level of the welding machine, you need to turn on the device in the ammeter mode, the incoming pulses must be equal to 44%.
- With the help of an amplifier and an optocoupler that transmit a signal to the unit, you can check the welding itself. The amplitude should be equal to 15 V.
- Using an oscilloscope, you can check the operation of the welding machine. If the pulses that will come from different windings are the same, then the operation of the inverter is performed correctly.
- At the end you need to check the inverter transformer under the control of capacitors. To do this, increase the skip level to 200 W, plug in an oscilloscope, and watch the beeps that will emit a collector-emitter.
Security measures when working with welding inverter
Welding is a very dangerous and traumatic type of work. And electric welding can strike the welder with an electric current. Therefore, all equipment, that is, the welding machine with which the welder works, must be properly grounded. This helps protect against electrical injury.
The next danger to human health is the ultraviolet spectrum of an electric arc. It can damage the organs of vision, skin and cause severe burns. Therefore, people who work with the welding machine must necessarily use special clothes and a mask intended for welding. It is desirable to protect other people from welding, because if you just look at the work of the welder, you can also get eye burns.
At observance of safety rules welding works will not bring harm to human life and health.
The welding inverter has many advantages, the main of which is its low weight.
In it, you can use electrodes and AC, and DC.