Comments on: Shorted IGBT K50T60 and 1N4744A In………

By: Yogesh Panchal

Yogesh Panchal — Sat, 21 Dec 2019 07:49:25 +0000

Good JOB! Waleed a welding machine specialist.

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By: Waleed Rishmawi

Waleed Rishmawi — Wed, 11 Dec 2019 18:30:47 +0000

In reply to Justice.

Justice: you are most welcome. Have a blessed day

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By: Justice

Justice — Tue, 10 Dec 2019 13:12:41 +0000

Excellent article Walleed thank you.

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By: Waleed Rishmawi

Waleed Rishmawi — Mon, 09 Dec 2019 09:03:09 +0000

In reply to Paris Azis.

Paris: yes, I usually buy ten parts from any sell and when I am content with the quality of these parts I buy later on more from the same seller. if a seller ran out of these part (so far so good) I do the same process.
about the 25 voltage reading, this is like a stand by voltages. once the welding process starts, the voltages usually go up and stay steady till the welding process is done.
on the other hand, there are welding machine that actually give you the actual welding voltages and not a stand by voltages. have a blessed day

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By: Waleed Rishmawi

Waleed Rishmawi — Mon, 09 Dec 2019 07:59:47 +0000

In reply to Albert van Bemmelen.

Albert: yes, the isolation piece is in good shape. it looked bad because the part was shorted on top of it. I always check these out in the final process when adding a new part and adding thermal paste to it. have a blessed day

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By: Paris Azis

Paris Azis — Sat, 07 Dec 2019 11:06:09 +0000

In reply to Waleed Rishmawi.

Hi Waleed

The relevant videos i have seen in YouTube about this parts' supplier are very disappointing! Anyway i have no personal experience since i never bought parts from there. If not found in our local market, i buy from England. At least it's the easiest way as long as that "Brexit" is delayed!
I noticed in a photo above that the voltage of the output of the welder is only 25 volt. This voltage is theoretically too small even to start an ignition spark. Do you know if this voltage stays in this level at the stand by stage only, that is, just before the first welding attempt, and then goes to a higher level (50 or 60 volt or even higher)? If your brother has tested it, will you let me know the result? (Not about the output voltage of course. Only about the "sticking" of the welding electrode).

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By: Waleed Rishmawi

Waleed Rishmawi — Sat, 07 Dec 2019 06:40:37 +0000

In reply to Parasuraman S.

Parasuraman: thanks man. you are such an encouragement to me. have a blessed day my friend.

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By: Waleed Rishmawi

Waleed Rishmawi — Sat, 07 Dec 2019 06:39:12 +0000

In reply to Paris Azis.

Paris: I buy them from Ali Express for a cheap price. They are very hard to be found in my home town and if I find some, they would be so expensive. I have tested out these parts from Ali Express and found them to be fit for such repair. have a blessed day

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By: Parasuraman S

Parasuraman S — Fri, 06 Dec 2019 11:01:33 +0000

Never ending welding machine failures, and there is one who will never give up on putting all of them back on track! Good job there, the only one unmatched!

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By: Albert van Bemmelen

Albert van Bemmelen — Fri, 06 Dec 2019 08:45:54 +0000

I hope that the isolation pieces on the big heat sink were all okay because one looked a bit damaged. Since you worked on that machine many times before it has no doubt been a troublesome machine. Seeing the damage on the semiconductors this time I wonder how much was damaged the other times?

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