That is awesome! Thank you ;) I'm glad that my knowledge is useful for someone...

@@DiodeGoneWild It's useful for a lot of people :) I would also like to thank you for your time: you taught me a lot about SMPSs especially the PFC part! I could never find any explanation so good as yours. I also appreciate your USB charger autopsies: I never knew what makes a charger good or bad. Now I know :) So again: Thank you so much for your time and I give the greatest of my appreciation for your content. Have a nice day, and greetings from Hungary!

@@smithcasey9785 But remember! His videos are not for education! Only diodes are allowed to go wild ;)

@@rkan2 🤣🤣🤣🤣🤣🤣

@@DiodeGoneWild Im learning electronics and all your autopsies give me a ton of practical examples of stuff I learn in an abstract way!

It is sisssteerrrrr's toooootttt Brooosshhhh...

☹

I hope he got it back before she noticed it gone.

😂

speedkar99 style!

Lots of time at home I guess...

He's uploading

Has much materials

DiodeGoneCrazy

*DiodeGoneBOOM or DiodeBOOM*

@@agustinusreynaldi7101 diodegoneboom sounds better

@@antkoos yes!

Yes i know, he makes the bests SMPS reviews, but they are too rare! He said in another video he was going to take a look at a 12V 50A 600W power supply, and he shown it, so he already has it! Still waiting for the review!

I agree.....but check this guy out too. His are also excellent, pretty understandable and very detailed: kzfaq.info/love/amuZ8n1PwdZpzxV32b1l_w

PSUs are easy to repair when it is only the diode bridge, input caps and fuse that blow. It gets more difficult when it is the switching transistors that die, especially if traces or component legs pass enough current to get vaporized. I'm not surprised that transistors survived: transistors in a bridge or center-tap configuration have to be rated for the maximum voltage they'll see during switching and that voltage is at least double what they should see when all transistors are off. Since the PSU is initially off when it gets plugged in at least until the auxiliary supply is able to start (typically 100+ms), current through capacitors likely blew the diodes and fuse long before the transistors were in any actual danger.

@@teardowndan5364 if one got on during the overvoltage, both would have been killed! The mosfet in the auxiliary power supply may be rated for 800V! I think it's more likely to be 600V, but it kind of survived! There is no active PFC, which of course would be good but it would need one or several mosfets with a chip and a big inductor! Those components are all expensive! What i still think is that 470uF capacitors are not enough as they are in series! I would put at least 680uF 250V into a 300W power supply! 250V also allows to have a better headroom!

@@Zebra_Paw When capacitors are significantly over-volted, their leakage current increases drastically similar to a MOV and it is this over-current that shorted out the first diode. When input polarity reverses for the next half-sine, the opposite diode is dumping straight into the shorted diode, fails too and now there is a dead short across the fuse. The transistors probably didn't even see 350V. Cheap PSUs are built down to a price and to hold up the outputs for 10ms or so between AC peaks at 300W, you need 3J of storage between peak capacitor bank voltage and cut-off. If peak is 320V and shut-off is 150V, then you only need 90uF of effective capacitance at 80% efficiency. A pair of 220uF capacitors in series is perfectly fine. You don't see 680uF primary capacitors (300+uF for APFC/450V) even in higher-quality PSUs until about 550W.

Recommended value for filtering mains is actually 1uF/W for 220V and 2uF/W for 110V, so need at least 680uF so that at 230V, the capacitors in series have 340uF capacity, and at 110V they will have their total capacity, 680uF, which is OK! I would add 150K resistors in parallel to each capacitor, so that when they are just in series the voltage is balanced better between them! But as they work with high voltage, i wouldn't have replaced them with 300mOhm ESR! And thank you but i had understand how the bridge rectifier died! But if it had the time to smell and spark, as DiodeGoneWild says, it could well have taken several seconds to trip, just as i did the same error with another power supply and only the capacitors died, everything else survived including the fuse! I wanted to replace the capacitors anyway because they were not looking reliable...

@@Zebra_Paw This is really a thing where manufacturers try to cut costs - smaller capacitors are cheaper.... Usually when electrolytes get too high voltage, they don't tend to fail suddenly - but there is more of a gradual increase in leakage current the larger the overvoltage gets. Until they either blow up or the circuitry feeding them, fails. As we saw - one capacitor was actually about to blow up, haha (since it was bulging), but the diodes failed first. If they get charged up to 325 V when rated for 200, the leakage current may be in the region of several amps - that combined with the pulsating action each half wave (as there is no pfc or inductor to limit current spikes), when the capacitors get charged up (or try to), may be well enough for those small diodes to overheat and fail rather quickly. Once they failed (shorted), they caused a short circuit of the mains input and blowed the fuse/tripped the circuit breaker. Although, if the input fuse of the supply would have been properly choosen, it should blow before the diodes. But that often requires fast acting semiconductor fuse (wich is more expensive than ordinary ones) - so I guess with that cheap ass supply, the manufacturer just added the fuse for safety (to minimize the risk of fire during a fault) and did not really care about protecting the components.

You may be right, but often all the disaster happens during just one halfcycle and so the other pair of diodes can't even be damaged.

@@DiodeGoneWild You are damn right about this. Absolutely

@@227suman besides the newer diodes are beefy, so the old ones will trip next time they try to run it at 110volts

@@DiodeGoneWild That could also explain why only one capacitor was (physically) damaged. On the lower voltage setting only one cap gets charged each half-cycle.

@@glmnetthats possible

Yes. Please do.

He should make a whole video about designing a SMPS from scratch.

@@taka4059 this is definitely hard from the point of calculations, and you need an oscilloscope, some datas about the ferrite core you are using, and so on... but otherwise it is not that difficult to make! I did it, a 5V 5A power supply to charge 3 phones at the same time! The voltage is very well regulated (it doesn't even drop 0.01V when i connect a device)! I can give you a schematic if you want but somebody else did the calculation for me and gave me a link for a transformer, so i can't tell you how to calculate...

@@Zebra_Paw There ist free software to calculate transformers, however I for example am somebody who wants to understand it. You can find many calcuations on the internet and they are all different, someone who does electronics as a hobby can explain it better and easier then someone at an engennering level.

@@PatrykDarasz i do electronics as a hobby and i completely agree with you. Well, i don't know how to calculate a flyback transformer and i am not the best for calculations but i can explain you how a s flyback power supply works while some engineers can't...

No _active_ PFC. There is some passive PFC

yeah, no pfc whatsoever isnt legal anymore.

Yes especially supervisor faults

1 year later, still didn't fix it, stripped the damn screws, voided my warranty and lost access to the circuit board. I will take it to my electrical repair friend, he will take a look at it. Unfortunately, I think the main IC may be bad. If can't be fixed, I'll keep the case and use my own circuit. This will lower the power capability, but it'll work again, and possibly even better, without any weird behavior. Also, before the unit died it killed one of my 12V circuits by a major 20V power surge.

yeah very sketchy to add those without warnings XD

I noticed that too. Always wondering what's the point of that. End user never sees/cares and PSU manufacturers surely know that.

You are not in the right video! This one is about a power supply!

@@Zebra_Paw It's never wrong to admire a soldering gun.

@@SianaGearz yes but he made a video just about the soldering gun

I'm to late but yes bro

To limit current in case of short circuit.

@@WolfGamerBohumin and reduce parts, which can be damaged, when short circuit is hapen 👍 clever idea👏

Luckily the 110V switch took two diodes completely out of the circuit by shorting them out, this is why they're still quite alive, and potentially even almost brand new.

Niiiiiiiiiiiiice

Yes, of course :)

@@DiodeGoneWild please do it.

Trace out the switch and imitate what it's doing. If i remember right, you can JUST remove the switch - in 230V position, the switch is unconnected! In 110V position, it bridges L or N to the centre tap of the two big capacitors following, essentially bypassing two of the diodes and turning the full bridge rectifier into a Delon doubler. So just disconnect the switch, no bridges. But double check that OK? I guess this is also why in this PSU, only two of the 4 input rectifier diodes went bust when the PSU was misconfigured. Because 110V switch has bypassed the other two diodes.

@@SianaGearz Thx much, last time I worked on it, I removed the switch and connected the 2 wires of the switch together, and did not works anymore. So only option was to reconnect back the switch at the time. I got that the switch is altering between 2 diode config 4 diode config. And yep I know that usually 220v use a 4 diode (to result as full bridge rectifier). So I guess I should work on that. I know also that something should be bridge on the board to imitate the switch, but a bit affraid and blow the poor device lol I guess I need to jump again into it, and first only remove the switch in 220v as you said and give it a try, before to bridge anything on the board ... And sure double check everything! Thx much for your recommandations and support ))

Often they're not easy to fix because everything is potted to a brick. Or the gears are worn or totally spun.