This is massively useful content :) I don't think there is anywhere else you will see such a well done practical analysis of smps's. I've worked with many engineers who could write a board full of formulas about power supplies but couldn't repair one if their life depended on it. This sort of practical knowledge is rare and getting rarer. A massive thank you to Diode for these videos.
@rjones85083 жыл бұрын
Absolutely true
@richardnanis3 жыл бұрын
I couldn't say it any better! Thumbs up for DGW!
@A6D6E63 жыл бұрын
Spot on ..........
@batkotivalio3 жыл бұрын
Absolutely agree!
@naseemqureshi1966 Жыл бұрын
Absolutely 💯 right 👍. My well wishes to Gentleman 💗
@BogdanSerban3 жыл бұрын
To rule out secondary side shortcircuits it's useful to plug a bench power supply at the outputs and see if there's any abnormal current draw. This can also be done at the input but a higher voltage is needed (above 40-60V DC). BTW these SMPS videos are absolute goldmine, I have the same ESR meter but it never occured to me that I can test transformers with it. I'm now trying to build a TSWF power supply.
@keithking19853 жыл бұрын
thats a great tip you shared there. thank you Bogdan : )
@jeffm27873 жыл бұрын
Would love to see that back in operation with a hand wound transformer with copper wire used. Bit of a pain I known, but would be nice.
@ithalkomedi15133 жыл бұрын
+
@giovinis3 жыл бұрын
i have being dreaming with that day since i born
@tigerelectronics59663 жыл бұрын
Hell yeah!
@krisd10003 жыл бұрын
He did
@jeffm27873 жыл бұрын
@@krisd1000 Yes, I watched the video moments after he released it.
@Conservator.3 жыл бұрын
1:20 They must have used a very high quality fuse that could withstand a 25A current! 🤣 Thank you for yet another very interesting and excellent video!
@abeleski3 жыл бұрын
Thank you. Would be nice to inspect the fuse and see how many amps it takes to blow it up. Its probably a fake fuse too.
@patriotinontourlive38543 жыл бұрын
I think, they used some pice of the primary winding - solid aluminium is best for 25A ! :O)
@michamaecki81043 жыл бұрын
That's possible - i've encountered similar situations in high-end power supplies. These fuses are just slower than good circuit breaker.
@Conservator.3 жыл бұрын
@@michamaecki8104 The 600W power supply tripped a 25A 230V circuit breaker (5750W) and it took a few seconds. 🤔
@michamaecki81043 жыл бұрын
@@Conservator. Yes, because fault initially didn't blew up transistor, that shorted mains. First transformer failed, and after 5s transistor and diode. Also, circuit breakers have solenoid that trips breaker at huge current surge much faster than ordinary fuse, so it's common to see power supplies with blown transistors and fuse intact. Also, to trip standard "B" circuit breaker in 5s, ti would need to see something around 75A.
@DrBeat-zs9eb3 жыл бұрын
Would love to see a repair of the power supply with explanation how to choose the right (real copper this time) wire for the transformer.
@vaclavtrpisovsky3 жыл бұрын
DiodeGoneWild's birthday is in three days!
@jayvadgama70763 жыл бұрын
😃😃and my on 18th...
@csala053 жыл бұрын
Tak že, dopredu všetko najlepšie majstre. 😀
@Purple4313 жыл бұрын
Mine in may 5 2007.
@Random_44003 жыл бұрын
How do you know 🤔
@Random_44003 жыл бұрын
@@Purple431 mine may 13 2005
@yodamaw3 жыл бұрын
Wind a new transformer to show how a good transformer should be winded.
@MrHD713 жыл бұрын
yes
@carlos_f3 жыл бұрын
yes please
@lunaticsterritory88683 жыл бұрын
Yaaap
@0124akash3 жыл бұрын
Yes
@philippezhang3 жыл бұрын
PLEASE
@Ariel-mq1pg3 жыл бұрын
i would love to see this working with rewinded chopper transformer.
@BobT363 жыл бұрын
This sort of vid should ABSOLUTELY be shown in electronics schools. Good job mate. As an electronics numpty I love your vids anyway, but I can really see the educational value here.
@piconano3 жыл бұрын
Now that's a nice SMPS video. I didn't think they would cheat even on the copper wire! I was wrong again. From the output rating to the parts used, all the cheapest possible.
@acoustic61 Жыл бұрын
Informative video. He may be the most resourceful technical person I've seen. And the dim bulb tester is a great tool to observe the power cycling.
@xavierm.34143 жыл бұрын
Since there were no shortage in the primary side, I would have tried the power supply without any current-limiting bulb, just in case the SMPS controller was disturbed by the voltage drop across the bulb. But you were 100% right, the transformer was faulty. Also, nice trick to test the bridge rectifier directly through the power cord. Very good explanation video
@emmanuelvallee53863 жыл бұрын
The SMPS controller only need a small voltage and current and DGW suspected the primary side of the transformer to be shorted and didn't want to fry again the chopper transistor and the diode again and therefore used a current limitation bulb
@xavierm.34143 жыл бұрын
@@emmanuelvallee5386 lol tu es là toi !! excellent
@naseemqureshi1966 Жыл бұрын
Thanks my friend for sacrificing your power supply and explaining the fault.❤
@ramingo.craftsman Жыл бұрын
I'm learning a lot thanks to your tutorials
@jms0193 жыл бұрын
One thing you said has me thinking. That a flyback design has an air-gapped transformer. My understanding is that it allows more energy to be stored for a given size (amount of core iron) and the nature of flybacks requires more energy storage. This is what I like about this chammel. Despite decades of experience there's always something new to learn
@esunayg3 жыл бұрын
no fix :/ I would be verry happy to see you rewind it with old copper wires :D, as always, good video dgw!
@ithalkomedi15133 жыл бұрын
+
@noelj623 жыл бұрын
Very very valuable information. Thank you.
@puyansude3 жыл бұрын
I am always impressed by your deep knowledge of the principles of fundamental electronics. Great work 👍👍👍
@lwiswrangnarzary93773 жыл бұрын
Very good knowledge of electronics
@subhobroto3 жыл бұрын
Great video! If over the next few episodes you can walk us through transformer design, winding, testing, that would be extremely appreciated and valuable. Upvoted
@idea-shack3 жыл бұрын
Really wanted to see you rewind the transformer properly and then re-test it at 50A!
@omaralkassab90793 жыл бұрын
Thank you dear for your great SMPS videos, I learned a lot of information about them... I can’t wait the reverse engineered schematic of it
@brucel.60783 жыл бұрын
Very genius!!! Amazing the things I learn here. And I like your cat, of course.
@SONYSony-em8dtАй бұрын
WOW i am amazed by your knowledge of electronics
@NullPointer3 жыл бұрын
I was about to ask if you have any videos about air gaps in transformers, but then i reached the end and got an excellent explanation! Great video!
@Alexelectricalengineering3 жыл бұрын
Will you fix it, I mean make a new transformer?
@ithalkomedi15133 жыл бұрын
+
@catalinbadalan44633 жыл бұрын
When you click the "like" button on a video before even seeing it, it's when you hit gold...
@jenda3863 жыл бұрын
It seems like the usual curse of cheap Chinese products: passable design, horrible execution. Had they used a transformer with copper windings and slightly better input caps (better meaning not smashed to smithereens in this case), odds are that the PSU could have worked for years.
@jms0193 жыл бұрын
or given it a realistic rating
@andreasu.35463 жыл бұрын
Passable design probably copied from other vendor's product.
@jms0193 жыл бұрын
Which is the ongoing problem with Chinese products
@smeezekitty3 жыл бұрын
@@jms019 I'm sure this was a 25-30A power supply they stuck a "50A" label on
@two_number_nines3 жыл бұрын
now a tutorial on its driver chip please. this is top 3 best electronics tutorial channels
@ricardoelectronicsrepair3 жыл бұрын
other comments: please build another transformer for this psu me: please build another transformer for this psu diodegonewild: schematic first
@ithalkomedi15133 жыл бұрын
+
@neerajsinghkaira45243 жыл бұрын
Please wind the transformer.. the supply needs it
@ithalkomedi15133 жыл бұрын
+
@josephe36973 жыл бұрын
DGW is a clever, knowledgeable man !
@Conservator.3 жыл бұрын
DiodeGoneWild Happy birthday!
@DiodeGoneWild3 жыл бұрын
Thanks :) How did you know?
@Conservator.3 жыл бұрын
@@DiodeGoneWild 😁 Someone commented that three days ago. I hope you’ll have a wondered day! (That someone was Václav Trpišovsky)
@marhoily3 жыл бұрын
I'm sure I'm not the first one to say it, but you have an absolutely captivating accent ;) Thought you an Indian at first. Awesome videos, keep it on!
@madanpatil15783 жыл бұрын
Highly informative and important to us this knowledge about smps transformers.
@noakeswalker3 жыл бұрын
Great analysis DGW ! Those impedance tests and demos really are educational :o)
@akshaykumarvyas3 жыл бұрын
Very educational video. You've made a huge effort. Thank you
@Orthosonic3 жыл бұрын
Love your accent... and content is absolutely top notch!!!
@N0G0MAIL3 жыл бұрын
Excellent review as always.
@adaniel693 жыл бұрын
please build a transformer for this power supply in order to make it work again! thanks
@ithalkomedi15133 жыл бұрын
+
@lakiza553 жыл бұрын
Weird how the primary OCP didn't prevent the obliteration of the diode and transistor, but works fine once you replaced the blown components and just the transformer primary shorted.
@DiodeGoneWild3 жыл бұрын
I think that the transistors and diodes would fail again if I left it on a bit longer... The overcurrent protection has a certain delay and with a very little impedance in the primary, the current rises very steeply when the transistors turn on. And the diodes have no heatsink, so they tend to overheat before the transistors do.
@SeanBZA3 жыл бұрын
@@DiodeGoneWild Typically the OCP circuit has a RC circuit on the input, to handle switching on transients that might cause premature switch off, so the current at turn on can rise fairly high, probably well past the SOA ratings of the transistors and diodes, with the shorted transformer. The overcurrent protection is there to normally handlke shorted output, where it will be transformed to a rising current in the primary, and also as cycle termination in normal operation, so it only has to be really operating near the end of the conduction cycle. Shorted primary the current rises very fast, and the turn off only occurs after the RC delay, so current is going to be limited only by ESR of the capacitors and the on state resistance of the MOSFETS, the dodgy capacitors here might ironically have enabled it to survive, as ERS would have been in the tens of ohms, limiting current pulses, though the output voltage would certainly not have been 12V at full load, dropping to whatever the capacitors allowed, with a very high mains ripple component as well. Diodes might not have failed, but the capacitors would definitely have gone boom and given a confetti shower.
@davidwang_music3 жыл бұрын
After watching a lot of your videos encountering doggy components and constructions, I decided to open my 48V 10A power supply and it turns out to be a BJT half bridge. However, my power supply is welly assembled, with no doggy components, and the semiconductors are mounted properly with heatsink compound. Unfortunately, I found out that the snubber resistors next to the secondary side diode are getting burning hot, so I replaced them with higher power ones and replaced output smoothing capacitors with low ESR ones. The only thing I found doggy was that they completely bypassed the inrush NTC thermistor...
@Purple4313 жыл бұрын
I like your makeshift thermometer :)
@ProdigalPorcupine3 жыл бұрын
Great video! Aluminium wire is the devil's work. Microwave oven transformers are wound with aluminium as well, but they don't even use copper plated wire. They use copper coloured varnish to make it look like copper wire.
@Graham-ce2yk3 жыл бұрын
I'd also like to see you repair it with a rewound transformer. It's a great opportunity to explain how to design one for a specific job. I hope the schematic explains what the missing components marked on the board are.
@radiotvrepair10593 жыл бұрын
Thanks for this vedio. why the impedance is high with a frequency of 100khz delivered by your esr meter
@PiotrK2022 Жыл бұрын
@DiodeGoneWild It is normal, wires may be stucked together. Why? Because SMPS transformers are winded and covered with insulation lackquer, just like classic, 50Hz, one... I disassembled good EI-33 transformer, and windings were also together and I noticed lacquer residue...
@BIGRIP873 жыл бұрын
hello, can please make a dedicated video on smps transformer designing? because you explain it very well and i liked your video
@lunaticsterritory88683 жыл бұрын
U should rewind the transformer and fix the dojy cheap chinese power supply...this will be interesting😊
@electronic79793 жыл бұрын
Very helpful video 👍
@robson62853 жыл бұрын
The explaining i look forward for! That forward switching is not totally clear to me. And you can abnormally good and clear explain such things. (Like that second outputdiode that works together whit that outputinductor, you made it totally clear to understand in just one sentence!)
@brucel.60783 жыл бұрын
HAPPY BIRTHDAY!!!!
@kna603 жыл бұрын
Very nice analysis and explanations, thank you very much !
@sup3rbird3 жыл бұрын
Very interesting and informative presentation. Lovely cat.
@milandjukic883 жыл бұрын
So enjoyable to watch 😊
@michaelfisher96713 жыл бұрын
Thanks Dany very interesting
@raffyturc3 жыл бұрын
and just because of an aluminum 'copper' wire, that the design failed. too bad. thats why im a bit skeptical about these cheap high power switchmodes
@Basement-Science3 жыл бұрын
I wouldn't say it would have been fine with the same diameter copper wire. The copper coating actually helps more than you may think because in a HF transformer the skin effect causes most of the current to run in the outer layer anyway, so not as much current wants to flow inside the aluminium anyway. So it depends on the thickness of the copper coating and of course the frequency how much better pure copper would be.
@mitropoulosilias2 жыл бұрын
well explained!! a thermal camera (flir) really helps on these troubleshootings but it is very expensive..
@sortofsmarter3 жыл бұрын
wow, that was great I never would have suspected aluminum wires in the transformer... I have a old 60A bench top power supply from 1950's that has a huge 10 inch transformer in it that uses aluminum wires but that was due to copper shortage because of the war. if I leave it on for long times it will get warm with no load...
@xicath3 жыл бұрын
interesting! maybe some capacitor or diode has been expire thats why its get hotter
@Geniusinventor3 жыл бұрын
More power supply videos please I love them 😘😘🤩
@filenotfound__38712 жыл бұрын
You should load test more power supplies.
@NickProcktor3 жыл бұрын
Imteresting video. I’m surprised nothing more than the mosfet and diode failed after the transformer shorted. It would be good to see if you can re-wimd the transformer with properr copper wire and see how much better the performance is, you just need to find a new bobbin. After that you’ll have a useful worrking power supply to use for something else.
@sayyidsahal45333 жыл бұрын
First I downloaded the video and watched it. Now I came back to comment you should rewind the transformer. Only a few numbers turn so it will be much easier.
@jesterraj3 жыл бұрын
Was intresting to see you using a esr meter to check the transformer.. what do you lookfor when usin this method...i have this same meter
@zx8401ztv3 жыл бұрын
Aluminium windings, what a con :-( I didn't expect that. Your cat would make a better supply :-D
@SeanBZA3 жыл бұрын
CCA wire is now so common in Chinese products that getting something without it is very rare now. They make it thinner and thinner, I suspect we will soon see all wire coming out from there in products being CCA wire soon, from power cables to the magnetics, with the only copper being PCB traces. The plugs and sockets they supply are getting thinner and thinner, with the metal content being reduced every year, and soon they will probably be going to copper or nickel plated steel for contacts in all products.
@zx8401ztv3 жыл бұрын
@@SeanBZA I had noticed mains power cables using coated aluminium but if the use is light at 240 volts it won't make a massive difference. It looks like we will all have to hoard real mains cables, ok i do anyway lol. I bet you have a few hanging around from previous computers and such.
@florind.57113 жыл бұрын
@@SeanBZA Tehnics uses CCAW on speakers for at least 20yrs
@stephanc71923 жыл бұрын
Great series!
@albertjansen59963 жыл бұрын
Would be nice to make a video with this restored transformer. Of couse with real copper windings. ;)
@ithalkomedi15133 жыл бұрын
+
@Chuckiele3 жыл бұрын
As the core of the transformer survived your disassembly, maybe you could rewind it with copper wire and see if the rest of the board still works? Besides the salvaged parts, poor assembly and aluminium wires, it seemed to be a decent power supply, just not 600W.
@stanimir41973 жыл бұрын
>decent power supply no thermal protection, no viable over current protection either (unknown voltage ripple - 4 caps on the secondary, tiny coil - for reference meanwell 12V/15A has 6 rubycon caps on the secondary). It's trash bin material - running even 30A w/o over temperature protection is just dumb
@Chuckiele3 жыл бұрын
@@stanimir4197 I obviously would never use it unattended. I never said its good, its not good at all, but its decent for a very low price. Its usable and cheap (I hope)
@stanimir41973 жыл бұрын
@@Chuckiele My point is that likely it has horrid voltage ripple - it was a massive disservice just to use it with incandescent bulbs and heater. They run on just rectified DC (no caps) or even AC. 600W and no power factor correction is another design flaw. Whatever I might connect to 12V /many amps will cost so much more than the power supply, no point to save money on power supply. It should be the most robust part of a system - a failure could burn anything connected to.
@jayvadgama70763 жыл бұрын
Happy Birthday Diode or D_____L 11-2-2021 you success fully survived 34 year.. Yes and thanks to @Václav Trpišovský for telling he's birth date.😅😃
@drewcrow53523 жыл бұрын
Is it possible that the insulating coating can function to allow the skin effect to take place? The tape will function to dissipate stray inductances? Thank you for the information on improved coupling. I have found resistive wire to handle heat. Perhaps the resistance/heat diminishes an inductive essence. What material was the coil inner written? If it is iron based ferrite, I would appreciate it's conductance as improving voltage capacity, and coupling for the coiled inductance as well.
@cluna52319 ай бұрын
Great information thank you.
@Langendimi5553 жыл бұрын
Aaah top quality chinesium transformer did it again! Nice video, thank you!
@JuanBataan3 жыл бұрын
Greetings from Philippines..
@JayPeeEV3 жыл бұрын
Idol
@JuanBataan3 жыл бұрын
@@JayPeeEV andito ka din pla hehe
@eded80453 жыл бұрын
and the lesson taken from this for china power supplys?? pick a higher power rating than you need and not push to max or rewind the transformer with copper wire and perhaps the Inductor. Rewind with copper for these supplys might be a good video we all can benefit from
@DuroLabs853 жыл бұрын
pls keep uploading videos like this
@ToleSan3 жыл бұрын
i interested on this topology since i build my two switch forward welding inverter based on your schematic. Cant wait for you next schematic video
@gamiwv3 жыл бұрын
EXCELLENT sir !
@nosafetyswitch93783 жыл бұрын
Why don't you wind the transformer properly now that you know the turns ratio etc? This looks like it would fix it ?
@stanimir41973 жыл бұрын
rewinding by hand is no fun and also it's not very likely to work at the same current (50A) even with copper wire. see 'skin effect'. The thing still needs proper temperature and over current protection.
@crusaderanimation69673 жыл бұрын
18:44 Well i hope your gonna tell )why this topology doesn't need air gap and have windings "in same direction", when flyback need air gap and windings are "reversed", also why those diodes gone wild on secondary side (:D) but i guess those is something strictly with topology so your gonna explain it any way .
@l_szabi3 жыл бұрын
In a forward, energy goes directly from the primary side through the transformer into the secondary side. In a flyback, energy from the primary goes into the "transformer" (not really a transformer, rather a coupled inductor pair), gets stored in the air gap, and then released later into the secondary. I'm not sure on the advantages of this topology, but DGW explains the workings very well in his flyback videos, USB charger videos for example.
@crusaderanimation69673 жыл бұрын
@@l_szabi Well I was watch in some videos about it (including diodes gone wild) so I know a bidt of theory (like flyback transformer is Inductor that stores energy) but I wonder what's difference "from transformer perspective" between taking energy by snober network and taking that energy into capacitor (especially that in some snober network there is capacitor that take that energy, just to dissipate it in resistor instead of reusing) like, from transformer point of view in both cases energy is pushed in and taken back so what's difference.
@informediatech-bruno57663 жыл бұрын
I bet the diode gone wild
@phenomenon91143 жыл бұрын
Why there are two diode on the out put 🤔🤔
@smithelectro-plumb29943 жыл бұрын
I really love you your videos sir you great and your explanation
@tvelektron3 жыл бұрын
Would be interesting to "test" the fuse, i have the feeling it may be faked to... Chris
@gicelectronics3 жыл бұрын
Thanks so much @Diode gone wild. Please share schematics.
@CXensation3 жыл бұрын
Check the fuse! It may look like a fuse but will not burn unless it is ridiculously overloaded. Which points to an inrush current problem with the design.
@batkotivalio3 жыл бұрын
Great thank you fo these videos!!!
@Basement-Science3 жыл бұрын
You should really get one of those Atmega328-based transistor testers. They are super cheap and can measure a lot more than your capacitor tester.
@republicoftutorials60683 жыл бұрын
Which topology is this ? is that forward converter ?
@leopaulevans75732 жыл бұрын
DiodeGoneWild what would cause a computer 19.5 v adapter to be showing 19.5 v when test but no able to power the computer ?
@Elektronenregen3 жыл бұрын
Nice Video! Good explanation :)
@Zenodilodon3 жыл бұрын
Eww aluminum windings, that's gross cheapness. Seeing this makes me even more cautious about buying PSUs from eBay that aren't name brand.
@hichamtassi17533 жыл бұрын
Hello, i have a uc3843 with very low switching frequency and then only have 1.65v at the exit. Any idea where to look at ?
@TZCoder3 жыл бұрын
My desktop PSU failed and I found a blown chip inside TNY280PN, what does this do and should it be possible to just replace the chip?
@nails7723 жыл бұрын
Subbed since 2016
@alvinsuriaga21432 жыл бұрын
Hello sir , active speaker is rated 1500 watts , at it seems the primary side is blown already cause of over voltage , the driver is ir2153 and no opto design , is there any way to mod the circuit?? Plese help men
@mikeatlanta93062 жыл бұрын
How can you tell which side of transformer is primary or secondary??
@__MINT_3 жыл бұрын
Will you rewind the transformer?
@ithalkomedi15133 жыл бұрын
+
@DavidMG993 жыл бұрын
👍👍 thanks for the info
@philippezhang3 жыл бұрын
thank you very much for sharing
@devinhales3 жыл бұрын
After counting the windings, can you add "Ah! Ah! Ahhh!" with some thunder sounds please?