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- Опубліковано 28 вер 2024
- Smoke in the EEVblog Lab!
What component failed and caught alight in the RD Tech DPS5020 Power Supply Module?
This was supposed to be a build video and review until it caught on fire!
Follow-up repair video: • EEVblog #1036 - PSU Fi...
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Aha, the classic rubber glove over the smoke detector trick. Very handy when things emit smoke unexpectedly.
bigclivedotcom ... said Clive packing a pair of rubber gloves in his case for the next business trip...
Ladyfolk with expensive hairdos.
whin will you burn somthing out in a exiting maner?
I'm surprised you chaps haven't wired a bypass switch on the smoke alarms.
*bigclivedotcom* Hey Clive, I don't know why I am surprised to see you here but I am.
just order some replacement magic smoke and put it back in, no worries
The video itself made me laugh so hard... and than enters this comment... :D
@@TheTinkerDad Well, you know those weird funnel things that come on the end of new meter probes. Those are complimentary magic smoke funnels!
I'm a quality provider of magic smoke. Give me some components and a few kilowatts and I'll make enough magic smoke to make Pablo Escobar jealous.
lmao
Coolest ceiling decoration ever!
Just remember to take it off before Health and Safety comes around, or you'll be emitting smoke from several holes on your body :-D
Be a pal Glen, post the schematic. Most people are more likely to buy a product that they know can be repaired, even after a fire. Your sales will skyrocket! It’s not like we can built one any cheaper than you anyway, just the parts would be more than $20!
The Combat Engineer The problem isn't us. It's all his local competitors in the Hong Kong suburbs (aka Schenzen).
I think that’s spot on.
Agree, $20 bucks for a very nice looking power supply - I thought he meant $20 for the case and external parts, that the power supply would be additional. I've looked at these kinds of power supplies through bangood but didn't trust them. Combat engineer, great name, I served with a combat engineer unit 2004-05 in Iraq. I have a lot of respect for those combat engineers. When thinking of this experience I though EVVblog was going to need to don his bomb suit, get out the demo robot and blow the thing up. The reality of building stuff is experiencing the joy of magic smoke. Sad to say I have installed a few parts backward or reversed my transistor looking from the bottom rather than the top. I think that is why you always buy a bag of transistors. Had a power surge go through my house this summer and it took out just about every switch mode power supply, magic smoke everywhere. House full of guest, TV smoking, the kids pointing ever which direction saying they heard a bang over here and over there. I ran and hit the main breaker then set about to determine the cause. Our cable had gone out and the cable man was fixing the cable when he disconnected the cable we lost the ground path for the severely out of balance load. The US uses a two live wires180 degrees out of phase with a neutral line to carry the difference in an unbalanced load. and if all fails a ground to earth ground. The neutral line had been chewed off by the squirrels, the house was using the ground to take the difference, 80 volts on one line, 140 or 180 on the other line, and that little coax cable was carrying a lot of the ground for the house load. I think the cable guy is a believer in those safety classes now. that high voltage and a lot of currents can be finding a path through their equipment. His eyes got as big as saucers when that thing sparked, he was shaking for 10 minutes. he had his work gloves on, I had warned him of a power problem that the previous cable guy said was happening in the area. The power company said they couldn't do anything about it, it was an act of nature. I would think that the expectation is to receive a proper supply voltage with the correct neutral. Well, it gave me a chance to change a bunch of little weird fuses, and thermistors. Surprisingly that is the only thing that blew. Able to get parts off of some old boards so it didn't cost anything to fix. I did through one LED light fixture away, I didn't even try to dig through all the epoxy and tiny parts. My old analog pinball machine dimed the lights and blew a fuse but nothing was harmed a fuse in the right place. The other pinball machine did not have any impact.
Isn't there a big ugly solder bridge short across 2 pins of the 48 pin IC, visible at 18:11? Perhaps this could be a contributor to the problem?
I saw that place , it should be solder splash, I guess Dave drop it mistakenly when he install the case , but there is nothing with the board, it control the display . this is not from our factory, because this chip was weld STM machine, it is impossible that there is the solder splash on 2 legs. we don't weld the chip by hand.
I'd say that cap suffered chronic electron diarrhoea, basically it shat itself... :P
I assembled the same kit with the buck/boost version a few months ago, works great from my 12v solar system.
I appreciate the "intrinsic defect" and thermal stress notes... valuable bits and pieces of info
I had the same problem 15 years ago. This (apparently) happend randomly
only to the capacitor soldered by hand. The capacitor was for DC supply filtering too. I found that the problem was due to:
- the very high temperature of the solder tip,
- the relatively long time to solder due to copper pours,
Without preheating the PCB, there is a temperature gradient on it and once both sides of the capacitor are soldered, there is a mechanical stress that could make some internal cracks.
I guess the problem is not only o the carbon of the fiber glass. Once the capacitor has entered on 'avalanche' (internal layers shorting more and more) the current is not 'smooth', and the output voltage of the power supply (adding the leads inductance too) could generate transient voltages higher than the MOSFETs 80 V.
Dave, it would be interesting to do a thermal image with the FLIR of the board when powered up. if it's really a conductive path between the output terminals, it should be possible to dremel out the burned pcb area inbetween. but maybe some of those mosfets (are they doing synchronous switching?) failed low resistance between drain and source.
The charring did indeed become conductive. Basically made a crude resistor.
I think the current is going through the burnt board. should test resistance then remove some of the burned board and see if the resistance goes down.
CrazyMonkeyCM32 thought the same, how didn't he try and scratch that
yes, those bunrt thing are shorted. just clean up that
Alexander Bukh
you can use a knife to clean those up
Dave you scared it to death That beefy one is just too much for the little guy
Great video. Those are called "Electrosplosive Capacitors". It looks like the cap failed due to Thermal Expansion Rate differences from the Board and Terminal Blocks, and possibly mechanical stress from flexing the power cables - which flexed the board and thus the cap to crack and short. Notice how the PCB didn't catch fire but was charred? This is why this type of PCB is FR-4 (Flame Resistant Material 4) - a fiberglass and resin material that usually won't catch fire if a component on board does.
The designer of this power supply was not well versed in decoupling caps and inductance. Those Terminal Blocks have a lot of inductance, so SMT caps which generally have low inductance are less effective close to the terminals because of the inductance. I have used similar Terminal Blocks like this before, I used large through hole caps near the Terminals because noise is not a problem there, it is power sag as the load changes which is the issue there. 100uf caps with low ESR and a WVDC rating of twice the max voltage is the way to go. You can't get those high values and large WVDC in SMT Ceramic caps, so you have to go with large Tantalum caps that can handle the thermal, mechanical, and in-rush current. Decoupling for noise (where you do indeed use Cermaic SMT caps) is done at the noise source - like at the switching transistors and digital circuits - not at the power output where inductance from the power cables alone block a lot of the high speed noise. Put a choke around the power leads if you ever see high speed noise get through the power supply to the load, those tiny SMT caps were doing very little for noise or power sagging, and I bet their voltage rating was only about 10% higher of the expected voltage - not enough design margin for high current applications.
Well here is the repair you have been looking for :P
just clean up those burnt things, that's ok
Hi, in other review of this thing on tube, was mentioned that if you want to use it with more than 30V you have to change this cap to more voltage. It was provided by manufacturer information...
Do you have a link to this information, please ?
Amazing amount of support from the supplier, I will try some RD tech products :)
I just received one of these power supplies today, and sure enough, C34 has been edited out. It’s completely gone on my unit. So hopefully that takes care of that!
we have already updated it , use the better capacitor
Oh, did you put C34 somewhere else? Or did you just remove it and make other changes?
Also, while I am talking to you. I'm still trying to assemble my unit. It's just like the one in this video - I have the DPS5020 power supply, and the grey metal case for everything. I am *nearly* there, but I am wondering if there are any assembly instructions you have, such as for the fan board? The fan board is the last thing I have to do, along with the switch. Do you have any manuals?
Thank you! Can't wait to get this power supply working. I also have your USB meter (the yellow one), and dummy load - loving both! I am going to order more, as well as some USB-C ones. Great quality stuff all round! Thank you!
@@uzaiyaro Hi friend
thank you so much for your message and your support, we already change a better capacitor and put it on the front .
for the installation instruction, B.choice 2 (suitable for with power board part product): www.mediafire.com/folder/rsbgws8grh6zo/communication_metal_houing_with_power_board
3.Installation video: ua-cam.com/video/ENZg4yTjhnY/v-deo.html
Rd Tech thank you so much! I’m nearly done with my build, I just have to wire the input side in. If I could kindly make a small suggestion; the crimp terminals you provide don’t fit the dies for any crimp tool I have.
I’ve actually been having a lot of problems with the supplied crimps, but if you supplied the crimps with the plastic sheathes, like the blue, yellow, and red crimps, that should fit a lot more tools and will make better connections.
May I also suggest using ring/eyelet crimps as well? Instead of the two prong style currently used. I found with the build that these two prong crimps tend to slip out if not held in.
Lastly, I’m finding that soldering the power switch can tend to damage it. If you include two spade crimp terminals in the kit, there wouldn’t need to be any soldering of the power switch.
Finally, just a question: has the issue of tightening down the terminals too much been fixed with the removal of the capacitor? I’d imagine it would be, but I have had to make the connections pretty tight so the crimps attach securely.
Thanks glen! It’s been fun putting this together, but the crimps are something I’ve had problems with. Everything else is going fairly smoothly though! Very nice kit. Please don’t take anything I’ve said as criticism, I’m just making a couple of friendly suggestions. Cheers!
@@uzaiyaro thank you very much for your suggestion.
and for your question about tighten, I don't suggest you let our PCB deformation
I may actually buy this unit - despite the fail in this vid. Just remove the bloody cap if the one i get shipped still has it. Yeah, would be a nice exercise to design a better one - but sheeeesh - tiiiime....gimme tiiiime.
I worked at a power supply company for 25 years - unregulated, linear, and switchmode. I started as a technician and plodded my way through engineering and management. Switch mode supplies are lightweight and compact BUT when something goes wrong you do get copious smoke and usually a little flame to go with it.
The engineering has to be just right and the parts quality has to be very good or they fill fail spectacularly. I have 4 power supplies on my workbench and everyone of them is a 40 year old linear supply made by old line companies. These can be had on ebay for very little money but it does cost a bit to ship these old boat anchors (a one KW supply will weigh more than 40 pounds). Replace the bulk caps and they go forever
From about 8:37 If you have 2 equal value caps in series, and one shorts out. Wouldn't it double the capacitance in that part of the circuit? Woudln't it just be like having one cap.
yes, you are right. in series, it will avoid this problem, but this capacitot and place are not good, we are updating
Yes, but the point Dave is making is you won't have a destructive short like in this video, because one cap is still good. The chances of both caps shorting at the same time is extremely small.
Yeah, but Dave said it would halve the capacitance when one shorted. It would actually double it. But Dave knows that, he was probably just loopy from the cap fumes.
Hyxtryx I thought he said it would halve the capacity under normal (nothing shorted) operation, which it would.
It would, but why would anybody do that? If it calls for a 100nf cap, and you want to take advantage of this "trick" (I'll call it), you wouldn't put 2 100nf caps in series, because you'd be left with 50nf during normal operation. You'd use 2 200nf caps to give you the 100nf capacitance the circuit called for. Then if one shorted you'd wind up with 200nf. Dave didn't spell it out completely, but I knew that's what he must have meant.
The latest versions are ok. The vulnerable cap is gone, and fan is quiet. Wonderful product.
Oh cool I've never seen stacked SMD capacitors like that, super funky.
Output is still shorted. Carbon is conductive. You've gotta cut/grind all that stuff out of there until you have bare fiberglass.
18:09 solder blob
Good catch with the sprinkler system!
Lot of carbon scoring here. Looks like you boys have seen a lot of action.
With all we've been through, sometimes I'm amazed we're in as good condition as we are !
1:45 I'm glad i'm not the only one having random leds stuck to the carpet :)
Great video, as usual.
My 2 cents words: the PCB layout designer did the mistake to place the unique SMD bottom component in the most unfortunate place: ceramic capacitor attached to metal screw connector. This is a beginer mistake. He/she did not take into account of the MECHANICAL stress. Should place a THD capacitor, or maybe this SMD but not exactly on the terminals.
Good that you published the video, thic ceramic capacitor is a ticking bomb for all these modules.
Luckily it can be easily repaired.
Cheers!
I think the rebooting was caused by current limitation set on the lab psu. As the device was powered on the terminal were cold. Dave set a voltage and current that exceeded what the lab psu would deliver with its settings at that moment. In that case the voltage from the lab psu dropped below the minimum voltage that the other device needed to operate. As soon as the micro controler threw its hands in the air the terminal where powered down and the supply voltage sprang back to a level where the uC could operate again.
My guess is that the terminals were still shorted, maybe bits of the charred PCB became conductive.
Fairly easy to repair.
yes, it is easiy to fix , he just remove the burnt things, that's ok
My electrical engineering prof's line was.
"When you see smoke in the electrical lab your are just getting started. When you see smoke in the electronics lab you are just finishing."
I'm surprised you didn't consider the PCB becoming conductive when it was carbonised. Wasn't that the issue with the previous isssue with the alarm system where the same thing happened?
I measured it and it was adequately high for a re-power up.
Was far too late to do anything else at that point.
Why didn't you repair it right away? I assume it had OCP and only thing broken is some cap and traces.
Wouldn't the burned pcb now have resistance around that area, so + and - and sense would basically be all linked.
@ 18:09 is that a short across the pins on the big IC in the bottom of the frame???
no, it is not that problem,. it is capacitor problem
Did the lack of feet block the cooling air inlet?
Def going to get one of these units ill wait a bit though! Ive already got a lower rated one and its excellent.
I notice at 15:39 the cooling fan over the mosfets is not on, thus no cooling. If they don't have thermal protection when active cooling fails, that little heatsink has no chance and; that could explain the smell and the thermal runaway / aka resistance and heat and fire?? no?
Hi! I'm buying this power supply, what do you suggest to do with the cap? Should I move it to the empty pads?
Rd Tech is making posts all over these comments - he says that you can remove it. I'd just check it out thoroughly and do the standard 'Smoke Test' to be sure otherwise it looks fine.
This is a well known failure mode. Multilayer ceramic capacitors are brittle. They should be mounted on the narrowest practical tracks/pads to avoid mechanical strain. Otherwise, as the solder solidifies, it shrinks and pulls the capacitor apart, forming a barely visible (under a microscope) crack. Do a search for the "Surface Mount Technology - Design Guidelines eBook" at "the-cool-book-shop" for more information. The malfunction after the capacitor was removed was probably caused by the carbonised PCB. You need a small burr on a "Dremel" type motor to grind away all traces of carbon. Then repair PCB with suitable epoxy. The capacitor is only there to remove high-frequency "noise". It can be replaced with a leaded type. Alternatively, use the same type of SMD but attach it with short, thin wires.
damn 50V 20A that's quite a lot of power ... doesn't surprise me at the bleeding edge of such high power density something popped
That's very promising PSU but cooling is SHIT.
I would see there cooling similar to that from the laptops with heat pipe and blower style fan.
When it was designed and tested this fan was installed on top of the mosfets just to bring their temp down to a comfortable level at full power since it obviously was seen necessary to keep a good lifetime out of it and they did the trick by this simple and easy way. Even if this type of cooling mounting is not the most efficient to cool a package like these mosfet its absolutely better then nothing and was also tested to be enough so I have no really problems with it as long as it works.
W/o a load to help suppress the HV spikes that a power supply like this *should* be expected to produce, even a 250V rated capacitor might not be adequate. The same part in series might work. The same part with a 200V varistor might work.
Watched the last review. Added the power supply to my shopping basket. Didn't click checkout. Decided to look around for more reviews. Then watched this video. Removed the item from the basket. Will be bringing my full scale lab power supply out of retirement instead.
These are fine as long as you don't use them at 100% input/output spec. I use mine with 36V in and 5-6A max and they are great and run cool at those loads.
Hi friend
don't worry
about this , I just explain this , the capacitor was compreessed by force. so it was shorted. now we are updating and choose a new place
Thanks for looking into this. I often go with Dave's recommendations when making purchases. If he does another positive review, I might reconsider. I've also had similar failures with caps in devices that I sometimes service. Fused caps, especially the tantalum ones. Never had one though that would bring down the entire board. Dave did try running the machine with an electrolytic in the end and there was still damage. I'd expect some form of short protection, a PTC fuse at the very least on whatever else that burned out. All of the lab supplies that I use can deal with output shorts no problem (but they also cost a lot more than this little gadget).
@Trump's Merkin
this is not the reason. our input is 60V, there is not any problem
@Dick Fageroni
you can try , my dear friend
trust me
Only thing I was sure Dave had ever built was a HV probe handle for an oscilloscope.
The fan isn't running: 14:47 when the output is turned on.
12:05 "JET FUEL DOESN'T MELT STEEL BEAMS!" No but exploding capacitors do...
Easy to tell where you've been on the web.
Just in case.... Jet fuel doesn't need to melt steel beams. It only needs to weaken it to below the design specs, and gravity will do the rest.
Oh hell, the 'Conspiracy Theorists' have arrived, Yawn!
But there is no way that a crashed 737 made those markings in the Pentagon!!!
I'm joking of course, just like everyone above is. So don't worry CoolKeys, I don't think any of the nutters are here. They all sodded off one they saw Dave's solar roadways videos.
and building 7? haha
If the board at the back detects smoke does it ramp up the fan speed?? :D
This thing is totally COUNTSED!
looks like a solder splash on the chip below the tl594c - bridging two pins to a through hole jumper
it is capacitor damaged, we already update this , and use a better capacitor
You should really contact the manufacturer before putting out such a video. This could ruin their business.
Manufacturer is RdTech, on this board now, conducting damage control.
the manufacturer had to test it more vigurousely, maybe they're going to make their tests better now. They expected free publicity, now they probably learned a good lesson, murphy is always where you don't expect
No, that's not how it works. You send your product and you take your chances. Stuff from Keysight, Extech and others have failed on camera, no one gets special treatment.
Engineers know "shit happens", it's a how company responds that matters. The fact that Glen is on here admitting it and saying it'll be fixed will grow his business rep, not ruin it.
What a nice discussion here. I like it.
Generally a very good signal-to-noise ratio in the comments on this channel, especially when Dave himself puts in a reply. :)
@18:23 I think there's a soldering bridge on the 64 pin IC, maybe that's the problem ?
no, friend , it is not that problem
Now I know my unit wasn't a just a bad batch... Too high failure rate on these units.
These are absolute junk....
First off I would like to state that I am not nearly as qualified as most when it comes to electronics engineering and circuitry . With that said, I'm sorry for may apparent harsh comment. I just happen to notice that Mr. Jones had uploaded a campfire video and so thought I could sing along or help carry firewood. I purchased two of these units a few months ago for a small project and one of them went "poof" are maybe "pop" fairly quickly (in a week or something) Thankfully they're not too awful expensive so I wrote it off as "eh, whatever.... no biggie, waste of money for a toy but they are kind of a fire hazard". As far having failure rate data, I can only compare my two units and Mr. Jones' unit (that would be awkward, I've heard Dave's .... never mind....) Not being totally comfortable with my public school education I decided to go upstairs and ask my Mom and she grounded me for watching porn again! So I "googled" failure rate calculations and can up with a MTBF of 15.5hrs, assuming Mr. Jones failed unit survived 24 continuous hrs + 3 hrs on my 1st failed unit + 5 hrs (so far ) on the 2nd surviving unit. Since the Pi calculator is still going and I can't find my lighter , I'm gonna go with 66% give or take 1% in unused kindling just shy of the apparent 70% required for scrutiny. With that I leave you with my respectful retraction of my first off the cuff comment , but as a consumer I wouldn't buy another "work in progress/fire hazard" beta project. Just my opinion.
too high ? there is data to agree with it
Funny how you always seem to hear about people with units with failures, you never hear about people complaining that their units work.
A few bad units doesn't mean that the whole line of product is crap, unless you have data that over 70% of total units fail, you can't say they are crap, sorry but try again.
Most probably some recycled / counterfeit component on the board gave up the ghost...Imagine you were not there, the whole place would have gone up in smoke...WOW!
Dave, smdh, you filmed yourself covering a smoke alarm in a shared office environment and then published the video for the world to see?
Understand your concern but i think it's maybe a bit harsh.
I'm all for safety, but the situation was clearly under control, and who knows what the cost of a fire response is for the office alarm, plus the inconvenience for neighbours.
Under the circumstances could you see it from the other side of the coin?
I've thought the exact same thing. I know that doing that is illegal in some countries.
Even if it's not illegal, it may not be something the building owner would want to see from their tenants. If the building happens to catch fire later, another tenant might sue the owner ~ "You had clear evidence that your other tenant was covering up the smoke alarm, and you did nothing to prevent this!"
Please provide Dave your address so he can send you the bill the next time it happens :P
Nothing worse than a bureaucrat. Got an iron rod up ur ass following every rule to the letter no matter how illogical, unnecessary and annoying as hell it is. Triggggeerrrred hahaha. Ok i'm good. (They're robots, Morty!)
and what about that second fan? why is that not turning?
Nice looking unit, the PCB design is good, although I'd probably go for more track separation because DC voltages love carbon tracks.
Always soak test new gear, the world is full of stillborn components. Most absurd I ever hit was IEC power lead on an oscilloscope that was a beautifully potted open circuit fresh out of the box. Tested all the new kit, another had a dead short in the once pristine now charred and bubbled standard plug :-(
Supplier had decided to save money by ordering default the US style leads and replacing them with brandless wholesale Oz style leads, which were also annoyingly short.
The instruments had been tested by plugging each one into the same lead rather than unpacking the new ones before dragging them up to the labs to set up.
??? did you test our products ?
Not to worry Dave, we all like to smell a little "magic smoke" in the morning :D
Board mounted caps over-heating on a video card caused the failure of my 'crucial' pc, probably with thousands of other XP-running pc's.(No, not online by then.)
Bummer though. No vague induction from the big power supply?
Soldering the SMD ceramic capacitor with too much solder create stress that cracked the fragile ceramics. Lite bit of solder create hight resistance. Non SMD capacitors with terminals do not suffer from that.
There’s a blob of solder between 2pins on the square chip just caught it at the bottom of a frame 19:59 below the tl594 ?
it is not that problem
You moved quick with the glove for smoke detector. Nice. You don't want that $1800 fire brigade bill...
I have one of these. It worked well for awhile, then suddenly, I am not getting the amperage I need. Was testing laser diodes. Inerded 4.5 Amps but despite setting it up correctly, I am not getting more than 1.25 amps! I have no idea why.
Oh Dave, don't you know that a charred PCB shorts the pins? A simple resistance measurement might be enough to check if that is the case. All the charring should bring scraped away before trying to run that again.
I did measure it and it wasn't a problem, but has now gone low.
What are the chances it was faulty and was between the outputs. That's two unlikely event together. I don't think it was a manufacturing defect.
I can see there is even a drop of solder on the pins of the mcu.
isn't input on that 50V maX?
I'd guess the board has turned into carbon where its burnt out, its conducting and forming a load on the output pins.
If the specs say input 50V why do you set it to 55V?
Looks like there was FOD by the Cap in the earlier photo, certainly poor soldering
Look at 18:12: There is a solderbridge on the 48 (4×12) pin Chip, right from R22 between Pin 23 to Pin 24 (When counting clockwise from the dot) .
And:
I would not apply such a high operating Voltage ever again to a PCB that burned sooooo black. This black stuff deep inside of the
PCB material is now slightly conductive for ever! ...
Why wasn't this little input capacitor placed behind the SMD PCB fuse from the power output...
At 18:09 it looks like a bad solder job on the larger (microcontroller?) chip, on the bottom right of the screen.
Bummer... My second unit just failed with constant 5.13v on the output. I replaced it with the minghe zxy 6005s. Seems more stable and it has a timer function that works nice for charging lithium's.
very good , if you have any question, please contact me
Is (was) it a tantal cap? Google for tantal and inrush current ...
Did I not see a splash of solder over the pins on a controller chip?
there is nothing with it
I'm going to put a sealed glass case in my lab, with a small hammer next to it and a rubber glove inside, with pictograms demonstrating how to break the glass, remove the glove and place it over the smoke detector!
When I saw the smoke I could instantly smell it xD
I'd love to see a video where all the components on a cheap board are swapped with name brand. Then stress test to determine name brand vs hung low
Dave: Are aware of the accidental solder join on the square chip (near C16)?
he will not care
It looks like's there's a solder bridge on of the TQFNs at 18:11. Can't see the designator.
the capacitor was damaged by force during installation. after the video we updated it , change the capacitor and place
Could one of the mosfets have shorted when the cap burned itself out?
no .. the MOS was fine, the capacitor is just damaged ...
It is likely the PCB conducting current as most burnt PCB's do. IMHO, KV4WM
the capacitor was damaged by force ,after power on, it was shorted to cause bunrt
Thanks man!
Ok...Let me start off saying that EEVBlog logo intro was badass..
Actually the blown capacitor was C4.
Ha you could have (ok should have) set the current to zero before applying power, then dialed up the current. You would have seen the load problem before critical failure.
SO that is what Samsung did with the leftover Note 6 parts
The updated version (which hopefully won't explode) is covered on my blog (plus video) - I've also taken a look at the serial interface as the software is freely downloadable for the PC.. thank heavens you spotted the exploding version. Up to now I love mine - tech.scargill.net/dps5020-diy-power-supply
thank you very much for your help
Time for a fume hood? How many radical carcinogens are produced by a flaming SMD capacitor? I hope my DP20V2A doesn't flame up like this when it gets here! Definitely time for you to get a Lotto ticket! :-)
we only add this capaciotor on DPS5020. now we are updating new place and new capacitor
Why would you want a power supply that runs at a lower voltage than mains? Why feed a power supply with a power supply?
because DPS5020 have good function, you just add a simple AC-DC power supply, that's ok , if you buy a same function AC-DC power supply, it will be big and more expensive
Don't turn it on, burn it apart!
Mine burnt on the ac input side between the + and - pins. can someone tell me type, size of fuse that goes there
? you put AC on the DPS5020 input ?
I have a DP30V5A coming and its input limit is 40V. Anyone know a circuit schematic to get a 40-0-40 6A transformer down to about 36V from 110 VAC?
Most simple circuits (full bridge and large capacitors, no regulator) will convert that 40V transformer to 56V. Too much for a DP30V5A.
Remember I have gluves near the bench... 😂
Hello. THIS IS how #EEVSMOKE should be. Thanks for interesting video.
Ha ha.! the ceramic cap looks already cracked in half before the magic smock. Look to the picture half way from the left the ceramic capacitor is cracked.
hes covered that smoke alarm before!!!
No comment.
Love the vids -- keep them coming
You know what they say, always keep a ladder and a glove near.
And, Glen. Lovely box. Can you tell me the name of the producer please?
Might have been an Xc/ESR/Ic-ripple convergence issue. when chip caps are energized as the voltage increases, the capacitance decreases, like significantly. so like RD Tech says, the cap is likely not even needed. The fiberglass cannot char, but the resin (usually a polyester) IS combustible given enough heat energy is dumped into it, then you end up with a carbon resistor (also why you wont see any carbon fiber PCB cores). One last thing, NO SUCH THING AS MAGIC SMOKE. GOD I hate that joke.
thank you so much for your explain
yes, it is just capacitor to reduce ripple at higher voltage , now we already improve it , use better capacitor and change the place
thank you
Hundreds of wonderful Ham Radio kits out there for testing. LMK if you have a pal doing such. Check out QRPGUYS and SotaBeams (UK--they speak your language) and QRPKits, and there are others. "QRP" means low power in Ham-speak. Of course we can build to "high power" but that requires much more expense and isn't really necessary when one understands RF propagation and efficiency. Bueller? anyone?