A Dead Welding Machine With Shorted Component Repaired. Model: Apex ARC-180
A welding technician brought this tiny welding machine for repair; he explained that it was taken to another repair tech, the machine got serviced but in two weeks time it was dead again.
The moment I took the cover off I was able to see that the fan in this welding machine was replaced for some reason.
It was the right size fan so I moved on to the other side of the board and checked for faults.
Here is the other side of the welding machine and I could see some work done on it. I did the de soldering of the IGBT’s but the components between these two is the area I am talking about.
The SMD components that is supposed to be 5.1R and 220 R were replaced with a tiny wires and I believe this was the reason this machine did not last long.
When checking with ohm setting on these two IGBT’s, there were supposed to be at least 27 ohm reading but now because of these wires, it was reading dead short even when the IGBT’s were de soldered off board.
When checking them with a multi meter, and as expected, the IGBT’s were shorted as seen in the photo. The part number is FGH60N60 and both had to be replaced on this welding machine.
The bridge rectifier was not shorted but it had to come out to be checked any way and at the same time add thermal paste to the component then install it back in the machine.
The wires added to these components were removed and replaced with the right parts.
At this time I was ready to check the machine and to see if I have the right voltages at the positive and negative of the welding machine output.
Yes, the voltages output as expected and the machine is ready to do some welding. Mission Accomplished.
This article was prepared for you by Waleed Rishmawi, one of our ‘Master Authors’ and currently working in the Bethlehem area of Palestine repairing electrical and electronic equipment.
P.S- Do you know of any your friends who would benefit from this content that you are reading now? If so, forward this website to your friends or you can invite your friends to subscribe to my newsletter for free in this Link.
Note: You can check his previous article on Welding Machine Powers On But Does Not Weld Repaired