Hello everyone, this is AC DC Adaptor from my electronic stuff.. this adaptor basically powers up hard drives externally and then we can connect it via USB to our computer.

I just powered it on and was checking, but as the connector is rusted, there was a spark while connecting the DC side and then a small blast inside the adaptor.

Next minute, i opened the box, i see some liquid spread out in a corner and also it smells acidic. I guess some capacitor is dead. I will inspect it closely and try to change damaged components. Lets see if we can give it a new life.

 

Both capacitors beside the LED are bad. They are badly bulging. It looks like one has ruptured (hence the goo spray).

It could be that they are both old and were ready to explode. Which happened. Replace both (and recommend replacing the other cap as well), clean up the board and case with alcohol. Then carefully (use eye protection) power the adapter. If something explodes, another component has gone bad. At that point, I’d junk it. If it doesn’t explode, carefully measure the output voltages to see if the adapter is working.

 

Both capacitors beside the LED are bad. They are badly bulging. It looks like one has ruptured (hence the goo spray).

It could be that they are both old and were ready to explode. Which happened. Replace both (and recommend replacing the other cap as well), clean up the board and case with alcohol. Then carefully (use eye protection) power the adapter. If something explodes, another component has gone bad. At that point, I’d junk it. If it doesn’t explode, carefully measure the output voltages to see if the adapter is working.

Thanks, your post is useful to me. In here, Alcohol is prohibited but surely there would be other cleaning liquids available in stores. Also, i need to buy safety eyewear.

If it doesn't work then i will desolder other useful components. i have many other junk items already, maybe i will try to make something out of it. Thanks again.

 

Just curious…

Alcohol is prohibited

Even medicinal denatured (undrinkable) rubbing alcohol?

That would work…

 

Thanks, your post is useful to me. In here, Alcohol is prohibited but surely there would be other cleaning liquids available in stores. Also, i need to buy safety eyewear.

If it doesn't work then i will desolder other useful components. i have many other junk items already, maybe i will try to make something out of it. Thanks again.

R14 has burnt out as well and must be replaced, but as we don't know its value, the unit is pretty much scrap anyway!

 

Just curious…
Even medicinal denatured (undrinkable) rubbing alcohol?
That would work…

Yes, we call it "spirit" in here, its available at medical stores and its used mostly to clean wounds. I will get it from medical store.

R14 has burnt out as well and must be replaced, but as we don't know its value, the unit is pretty much scrap anyway!

I havent taken a close look yet i will work on it and then give update. Thanks.

 

I think this diode is shorted. (and capacitor is dead) There are probably other problems.

 

I think this diode is shorted. (and capacitor is dead) There are probably other problems.

Thanks @ronsimpson I am working on it and will give update.
For now, i can confirm that it wont work..!

 

Well, i checked the circuit and found many problems. The two capacitors, fuse, transistor and R14, they are all damaged. The Diodes are working.

I tried to salvage the led, cable, headsink and the big capacitor, AC input connector. it may be useful for some other circuit in future. I will also desolder the coil and its brass wire could be useful.

Thanks @djsfantasi @sarahMCML @ronsimpson for your inputs.