May I ask what is the reason why the AC welding machine cannot start the arc when welding with a lot

1. After the welding machine is energized, an alternating magnetic field is generated, and some parts such as the moving core vibrate due to unbalanced force, resulting in noise. This includes:

1) Vibration of the moving core;

2) vibration of the static core;

3) vibration of the box cover;

4) Vibration of the fan;

5) Vibration caused by other reasons, such as uneven chassis and uneven ground.

Among the above 5 reasons, only the first reason, that is, the vibration of the moving iron, is the main cause of noise and is not easy to eliminate, and the other 4 reasons are secondary causes and can be easily eliminated.

There are 3 reasons for the vibration of the moving iron

1) The manufacturing accuracy of the moving iron core is low;

2) The gap between the moving core and the static iron core - the air gap is uneven;

3) The matching accuracy of the parts supporting the moving core and the connecting parts is low.

Second, the arc breakage of the welding machine is a problem often encountered in the use of the welding machine, which can be roughly divided into two categories, one is the welding machine itself in the manufacturing process due to improper design, cutting corners and other reasons. That is, the dynamic characteristics of the welding machine are not good, so that the arc is slightly elongated and the arc is extinguished, and the welding process is very difficult, and the welding quality cannot be guaranteed. This condition is congenital and there is no way to fix it.

There is also a category of welding rods, power supply voltage, welding current selection, and welding circuits. and other reasons.

The problem of welding rods, mainly the quality and model of welding rods, as an ordinary AC arc welding machine, the most suitable welding rod is an ordinary acid welding rod, if the alkaline welding rod is used, the probability of arc breakage is very large, as for the quality of the welding rod, because the technology of the welding rod manufacturers is uneven, there are some welding rods themselves that are easy to break the arc, which has nothing to do with the welding machine itself. If the supply voltage is too low, the no-load voltage will be low, and the arc will break. The welding current is too small and the use of large diameter electrodes will also break the arc.

Poor contact of the welding circuit and the arc break will also occur if the welding wire is too thin.

It is certain that the secondary winding of the transformer is short-circuited, you carefully check whether the secondary winding has insulation damage that causes a short circuit between turns, and then the insulation of the output terminal is damaged through the chassis short circuit, and the solder wire is damaged and short-circuited can also cause this fault phenomenon.

First, let's look at three-phase electricity first.

There is no phase loss, and then look at whether the fan is broken and does not work, the fan does not work and welds for a while, and the protection light is on and cannot work, which is called overheating protection. You can change the fan to one another.

Second, see whether the ground wire and the solder wire are in good contact.

Third, the MOSFET.

There is a breakdown, resulting in the overcurrent protection of the welding machine. This necessitates the replacement of the MOSFET.

[The reason why the DC welding machine does not arc].

1. The circuit of the welding machine itself is damaged and there is no output;

2. The welding torch switch is damaged, and the welding torch switch gives the welding machine a start welding signal when pressed, and the welding machine gives the output.

3. To heat the electrode, it is recommended that the electrode be placed in the electrode insulation barrel, and the wet electrode will also cause arc initiation difficulties.

4. The ground wire should be clamped with a special ground wire. In addition, the workpiece is seriously corroded, and poor conductivity will also make arcing difficult.

In addition, it should be done: the input line is not less than 4 square millimeters of copper cable, not more than 5 meters. to ensure sufficient capacity.

The output line is made of 35 square millimeters of welding handle special flexible cable, not more than 8 meters. In order to ensure that the output current and voltage drop will not affect the welding parameters, and ensure the stability of the output welding parameters.

For the electrode arc welding machine and TIG (argon arc welding) welding machine, the welding machine will not be burned, because the output characteristics of these two welding machines belong to the descending characteristics or constant current characteristics, the short-circuit current is not much larger than the welding current, and the voltage during the short circuit is very low, much lower than that during welding, so the input power of the welding machine is much smaller than that during welding, and the power consumption is small, so it will not burn the welding machine.

However, a long-term short circuit at the output end of the carbon dioxide gas shielded welding machine may burn the welding machine, because the output characteristics of this welding machine are flat characteristics (constant voltage), the short-circuit power is relatively large, and the long-term short circuit is easy to cause the failure of the welding machine or the welding machine.

Because the welding machine has a current clamp, even if the output is short-circuited, the current is immediately limited to the set welding current value.