PC ran at WRONG VOLTAGE! Can I fix it?

[@adnanmlivo5885]

I got a job in an led lighting store becouse of you! You are the best teacher ever.I work on fixing psu's all day and i love it. As soon as the first pay check comes in i'm supporting You on Patreon.I owe you way more than you will ever know.Greetings from bosnia.

[@DiodeGoneWild]

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

[@smithcasey9785]

@@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!

[@rkan2]

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

[@cisarvialpando7412]

@@rkan2 🤣🤣🤣🤣🤣🤣

[@martovify]

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

[@jutukka]

"...my sister's tooth brush.." 😂

[@PCbolt17]

It is sisssteerrrrr's toooootttt Brooosshhhh...

[@HazeAnderson]

☹

[@Mentorcase]

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

[@andiyladdie3188]

😂

[@Martinsp16]

speedkar99 style!

[@taka4059]

Another upload already! This is too good to be true.

[@AlexanderBurgers]

gotta love that they replaced the PFC by just.. big letters 'PFC' on the board.

[@samuelecaldini4400]

3 videos in 4 days, what's happening?

[@gytax01]

Lots of time at home I guess...

[@SamuelBl4ck]

He's uploading

[@roseelectronics4582]

DiodeGoneCrazy

[@math3390]

The best video about repairing SMPS I seen on KZbin, ive watched a lot of them. Good work!

[@Zebra_Paw]

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!

[@Langendimi555]

#DiodesGoneShort

[@antkoos]

@Agustinus Reynaldi diodegoneboom sounds better

[@Zebra_Paw]

@@antkoos yes!

[@Rodox2k10]

Using his Electronics knowledge in order to re-purpose a dumped WORKING device. I wish I had your knowledge to do the same. We've got A MOUNTAIN of WORKING devices like that PSU waiting for us around the world. And it never stops growing.

[@hugoegon8148]

Just to mention, you replaced 105°C capacitors by 85°C ones. That will result in shorter lifetime if power supply will become warm usually, what is mostly the case.

[@menix2384]

Thanks for the video. I recently blew a PSU by choosing a wrong voltage, I gave up on repairing it after I blew another fuse, but I realized I forgot to check for shorts. Turns out the bridge rectifier is shorted across AC, and replacing it brought the PSU back to life!

[@PatrykDarasz]

Please make a video how to design and calculate flyback transformers...

[@willtipton]

Yes. Please do.

[@taka4059]

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

[@Zebra_Paw]

@@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...

[@PatrykDarasz]

@@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.

[@Zebra_Paw]

@@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...

[@zx8401ztv]

Can you repair it, that's funny, you design switchmodes lol. It looked like a good psu untill you removed the case, then ahh cheap 250w one. They didn't even add the input inductance to help the power factor at full power. I'm really supprised that the driver transistors did not die with double the voltage, maybe they were over rated. The good thing is cheap supplys are simpler to modify for other uses :-D

[@teardowndan5364]

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.

[@Zebra_Paw]

@@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!

[@teardowndan5364]

@@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.

[@Zebra_Paw]

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...

[@Speeder84XL]

@@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.

[@klydolph2]

Great video Daniel. I once remember reading that if some of the diodes in a bridge rectifier are blown it is good practice to replace all 4 of them. The ones still measuring good have taken a hit and can blow before they should.

[@DiodeGoneWild]

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.

[@227suman]

@@DiodeGoneWild You are damn right about this. Absolutely

[@glmnet]

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

[@eDoc2020]

@@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.

[@227suman]

@@glmnetthats possible

[@HugforYou]

Thank you for showing us! Please support all the sympathtic and very competent DGW !!! 👏😊

[@aperson9375]

It was one of the needed upload everyone waited for Thanks.

[@TomaszStachewicz]

yours are the best videos about switching power supplies on the entire youtube

[@englishrupe01]

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

[@saarike]

Simply excellent Mr DiodeGoneWild! Thank you.

[@simontay4851]

You should remove the voltage selection switch. It is not used for 230V mains.

[@kemalkurt5257]

Very well Diode Gone Wild you upload so much, too good to be true

[@jawjuk]

No Power Factor Correction bu the board is marked "PFC" like some kinda inside joke.

[@smeezekitty]

No _active_ PFC. There is some passive PFC

[@Chuckiele]

yeah, no pfc whatsoever isnt legal anymore.

[@fifififi9959]

I built once DIY halfbridge from IGBT's and I forgot to switch the ciruit from doubler to rectifier. But none of the semiconductors has been damaged, just main 400v caps exploded, emitting enormous smell :)

[@somewaresim]

Excellent stuff! I also loved the dry comment about your sister's toothbrush! :)

[@chaosminecraft3399]

The line "using the toothbrush of my sister" was a strong move. 😂😅

[@erikbertram6019]

8:29 Also the required capacitance is decreased because of the reduced current drawn by the power supply.

[@akkudakkupl]

I need a transformer soldering gun for those big copper planes too

[@Zebra_Paw]

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

[@SianaGearz]

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

[@Zebra_Paw]

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

[@lightbulbgonewild3205]

Just 30 seconds in and he is already taking it to bits :D

[@LarryKapp1]

Nice to get an easier fix this time !

[@kernel_data_inpage_error]

Love how this guy makes content with almost everything, that power supply is so cheap I would not even bother fixing it at all, they give them away with some 30 € cases and is the kind of power supply you DON'T want to use in any build (probably on an SBC low power Celeron like CPU) I bet it wouldnt provide past 300 watt at most

[@filenotfound__3871]

PSU repairs are the best to learn electronics

[@ervinsz]

Yes especially supervisor faults

[@mattdude]

Years ago I had a computer with one of those voltage switches. I didn’t know what it was at the time so I switched it to 230. Luckily, since we only have 120 volts the computer simply didn’t turn on.

[@Bushougoma]

I wouldn't call Fuhjyyu capacitors better replaced tons of those that failed on the secondary side of Antec SmartPower power supplies back in the mid 2000s. Since these are on the mains side and aren't stressed at high frequency they should be fine. Still for me the only place for Fuhjyyu caps is the bin. I wouldn't use them anywhere.

[@julianslab1511]

DiodeGomeWild: Okay I blew the high voltage primary side regulator caps and the main fuse of the pc... DiodeGoneWild's mum: WHAT DID YOU DO TO MY COMPUTER?!?!?!?!?! ARRRRRRGGGGGGGHHHHHHH!!!!!!! DIODEGONEWILD!!!!!!!!!!!!!

[@MKBrno]

Fakt dobrej kulturní zážitek, toto!

[@Plan-C]

Just the ticket. I have one of these I have been meaning to look at for a while that belongs to a friend. Good stuff.

[@ix.cryo1]

The red fan looks pretty cool ngl

[@em0_tion]

I remembered my DMMs can measure capacitance and marked the selector on my amp clamp dial as well. I learned 2 very useful things from this video, so THANK YOU! :) Fire extinguisher bump 🍻

[@EasyOne]

Very well explained

[@unginc1504]

My bench power suplly was ran at double the voltage after its step down transformer shorted out enternaly, it was made in maybe the 70s so it is a tough little thing and it survived

[@Georgy-fg3bg]

I have tried that the my sister's toothbrush is even better suited for cleaning the cat toilet.

[@A6D6E6]

Niiiiiiiiiiiiice

[@franzliszt8576]

The problem was that they didnt put warnings on it like those other ones ;)

[@marclenraymagdaraog691]

yeah very sketchy to add those without warnings XD

[@williama29]

I love watching your videos

[@SidneyCritic]

HaHa, Julian Ilett just took apart a drill speed controller.

[@electronic7979]

Helpful video

[@serotonin336]

I am a doctor not an engineer but i watch your videos cause i love ur accent

[@DrZipZwan]

Same, I am a doctor too, and I like electonic and fixing stuff when I can ))

[@serotonin336]

Me too it's a hobby like any other hobby

[@gytax01]

You make everything seem so easy :D

[@mohitsorout6669]

Love those repair videos👍👍👍

[@wdujsub7902]

I love your videos, I always learn so much from them, please keep making them

[@danthompsett2894]

Wow you really know your stuff dude well impressed

[@UnrealWaifuTV]

I really want to check the ripple of that PSU under load...

[@l0k048]

video tittle: Fixing power supply me: oh no * video starts and i hear a thick russian ascent* me: _O H N O_

[@theodiscusgaming3909]

He's Czech, not Russian

[@brucel.6078]

Why you are not college professor?!! You very good at teaching!! Thank you.

[@RespawnRestricted]

How do them switches work that halve the voltage

[@SlinkyStoney]

Attempted to fix one psu with two blown transistors and fuse was not blown. I replaced the transistors with the exact numbers then tested, works fine on standby but when I power it on the fuse was blown.

[@richardnanis]

Yet another excellent repair video! Pls show us how to modify output voltage on bigger server psu :-) - or just ATX-power supply.

[@yuumi925]

Beat content and good fix on that powersupply. Love your accent.

[@foxmoulder2430]

Nice Repair 👍🙂

[@radiotvrepair1059]

Thanks for this vedio . why are you changing the capacitors do they have a big esr.

[@toddt6730]

I used to discharge the capacitors with a two watt 100 ohm resistor

[@MuhammadDaudkhanTV100]

Beautiful ideas

[@adamsucksatyt]

I got an switch-mode adjustable power supply, and it blew up. Input voltage was set to the right voltage. Somehow the current regulating circuit sometimes fails, and in my case, it happened while I was setting the current limit. Suddenly, I got 11,5A from a 10A power supply, and after a short while, something popped loudly and the fuse blew up. Taking it apart, I can't find any damaged components, but maybe it's not damaged, I just quickly turned it off, and the current limiting thermistor was still warmed up. Maybe it's the thermistor, or a more serious primary side issue. Did the failure of the regulator overload the the main power supply?

[@imnotbeluga007]

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.

[@Zebra_Paw]

I think the ESR of the original capacitors was OK, just they were supposed to be 220uF and they put a fake 470uF rating! But anyway for 300W in this topology this was too low rating...

[@santi308]

In my experecience is better replace all four diodes on bridge rectifier because the old ones tend to fail. This is a cheap dodgy psu no power factor correction, no vrms but the real deal are the voltages in it 12v line is 0.5v low. -12 is 1.5v low (or high? huh) and 3.3 5v are high for the motherboard. It works but you never put a gpu. If your psu doesn't have 6+2 gpu pin connector don't put a molex to 6+2 gpu adaptor because it can blow up

[@SianaGearz]

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.

[@Ncky]

Can you tell me how can i get out 2X50V from yours "Switched power supply 2x 35V 350W" ?

[@hitbyathunder]

Wow Good Thubnail! Keep it up!

[@TXPer]

diodes gone wild

[@Tsiikki]

Thanks, you're genius!

[@nahuelbordon2691]

I just blew my PSU this way a moment ago. The pc was connected, but turned off. I hope nothing else got screwed, because everything is so damn expensive in my country right now, and it will get worse with each month 🤦‍♂️

[@davidpolacek4902]

Super video, bylo by lepší vyměnit všechny diody v usměrňovači, už můžou být načlé, zvenku zdroj vypadá hezky, ale vevnitř je to ten nejobyčejnější, a tak velký výkon bez pfc - chudák sinusovka bude mít zplacatěné vršky a spodky :-D

[@miklov]

I also prefer illuminating halogen resistors for test loads =)

[@arcinin1]

Top shelf PSU - Bandit Power

[@zUltra3D]

If he thinks that a dusty fan is disgusting, wait till he sees some gems in the pc master race

[@StigDesign]

I remember this as a trick at school in Norway when i was young in the 90s that is so windows 95 and windows 98 computers usually ibm pc`s, usually the circuit breaker didnt react but psu said booom XD

[@michaeltempsch5282]

Å school that doesn't fix/lock those switches with something like epoxy is just asking for it...

[@StigDesign]

@@michaeltempsch5282 hehe Yes :D

[@BobT36]

Electronics noob here, what's that dish that you put the soldering gun into, is it to help the solder stick or something?

[@Ale.K7]

It is/was usual for the capacitors on the primary of very cheap no brand computer power supplies to have fake ratings... They say 220, 330 or 470uF, but are usually all 220uF ("better" but still cheap, no brand PSUs tended to have real values). It is/was not very uncommon for them to have also fake brand names.

[@peraperic5270]

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

[@0010-d3w]

hello diode , i got fsp 850w gold hydro G , it don't start , green and black have 1450 ohm , any advice how to repair it or what to do please ?

[@nikiamz6501]

I love the thumbnail !

[@Waaasil]

Thank you very much, well done

[@joselynagoncillo8744]

The chopper or transformer seems to have a hole. Why was it not pointed out? It could be seen in 01:33.

[@CyberTechSRB]

What if you replace capacitor with higher value but same voltage? (200v) it's good or will create problems??

[@DrHouse-zs9eb]

No PFC with that high power? Is that compliant?

[@godfreypoon5148]

It's ok, they wrote "PFC" on the board in a weird looking font. Compliant.

[@Basement-Science]

It might be old enough where it wasnt mandatory yet.

[@DrHouse-zs9eb]

@@Basement-Science but it looks relatively new. Old ones weren't black and red colored.

[@DiodeGoneWild]

Maybe PFC wasn't required when it was made or... they didn't care :).

[@DiodeGoneWild]

It's quite an obsolete construction, but it tries to look posh and modern by painting the box black and using a giant red fan :).

[@siavasharash5448]

Hello my friend diode. Finally i get confused. Whan you can visually seen 230 on that switch it means what? Dose ot meen it set on 230?

[@andyapple9]

Can you please why did you put the 300w lamp in series on 230Vac line? thanks!

[@WolfGamerBohumin]

To limit current in case of short circuit.

[@Cyklon-A]

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

[@englishrupe01]

Great job! Thank you for the video!

[@planespottingbacau6980]

It happened to me one time, but instead of tripping the breaker, the power supply caught fire, lucky me and my dad were around.

[@CHGOfficial512]

Exactly this happened to me a moment ago, Please tell, is there a risk that pc components connected to the power supply at that moment were damaged?

[@mh0rst]

I killed my first own computer this way back when I was 6 years old. It spewed white smoke out the PSU and smelled horribly. Scared the living sh*t out of me. At least it taught me to respect electronics running on mains voltage.

[@mihai._.despinoiu]

My power supply's 3.3V lines are dead. What may be the case? Thx

[@mihai._.despinoiu]

@@0verv0ltage Thank you for the reply

[@vaclavtrpisovsky]

@@0verv0ltage Or it may be one of those well-regulated power supplies that contain a giant 12V PSU and buck converters for lower voltages + a voltage invertor for -12V. In that case, the 3V3 buck converter likely failed. If you cannot repair it, try buying an external one.

[@mihai._.despinoiu]

@@vaclavtrpisovsky i use the psu for experiemental use, not for pc. its a 500w psu atx

[@catalinbadalan4463]

Does it says "pFC" in the unpopulated lower left area of the PCB!!???

[@phenom9333]

Sister’s toothbrush lol 😂

[@HugforYou]

😂😂

[@tristanginod9238]

Good video about the repair, but I don't recommend to use this power supply in a computer because it has a crappy design... Well, not so bad for a 200-250W PSU, but it's rated 500W, absolutely insane ! Also the capacitors are very cheap (chang capacitor). I already see a PSU like this, with a fake PFC and an inductor made of scrap metal pieces… Those power supply make the motherboard’s capacitors and CPU’s regulators blow.

[@JendaLinda]

Bodejť by měl aktivní PFC, když nemá PFC vůbec. Ty kondenzátory byly nejspíš nekvalitní. Chong nepatří mezi důvěryhodné výrobce. Ale možná právě díky tomu tranzistory přežily. :-)

[@snipersquad100]

nice job

[@avaydon7679]

Not sure though, but Electrolytic capacitors resistance varies by different color caps, you replaced Black one for the Blue one, Black ones have low ESR value for precision filter and cheap Orange one have high ESR.

[@eDoc2020]

I believe the colors vary by brand so you can't compare them that way. Plus the primary of a mains power supply usually isn't picky about its capacitors.

[@1pcfred]

The color of the jacket sleeve has nothing to do with a capacitor's rating. Every manufacturer uses whatever they use.

[@filenotfound__3871]

Mine was cooked, had the exact same one, the same cause, but the breaker didnt trip...

[@abhishekkushwaha2455]

I also had this type of PSU, in my case breaker didn't trip and it results in burning my motherboard, hard disk, Dvd drive and ram.

[@filenotfound__3871]

@@abhishekkushwaha2455 F

[@bassboosted5874]

W..wait? You can turn those things to switch the voltage?

[@Debraj1978]

Obviously, you can fix it. I came in to see, how difficult/ easy is it to fix.

[@desmondhow343]

I have a drill like that can't wait for how to fix it because mine also broke

[@rkan2]

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

[@cyrax4144]

0:14 So the switch here in which mode? Is it on 220v? Or 110v?

[@TheRintincola]

That red button is a danger !!

[@andiyladdie3188]

I bet the case of the PSU with the cable harness plus the fan, cost much than the pcb and components inside it 😅