Although I've come across some really dodgy power supplies with poor insulation between the mains and low voltage sides, this is the first one where the USB ports have carried full mains current. (via a rectifier)
It's a Swees QY08-05010 with this model and style carrying various other branding as well. Oddly it does appear to be relatively sensibly designed inside, but this one has a serious manufacturing fault that suggests others from the same run may also pose a risk of serious electric shock.
Sadly, this just reinforces my doubts about the poor separation in many of these small transformers. I'd rather have split bobbin transformers even if it meant efficiency taking a slight hit.
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It's a Swees QY08-05010 with this model and style carrying various other branding as well. Oddly it does appear to be relatively sensibly designed inside, but this one has a serious manufacturing fault that suggests others from the same run may also pose a risk of serious electric shock.
Sadly, this just reinforces my doubts about the poor separation in many of these small transformers. I'd rather have split bobbin transformers even if it meant efficiency taking a slight hit.
If you enjoy this channel you can help support it with a dollar for cookies, coffee and dangerous power supplies at https://www.patreon.com/bigclive
I used to work for a power supply company. All transformers, common mode filters, and final product needed to pass hi-pot to be sold. This should not have left the factory.
It sucks because the manufacturers of the power supply seem to have put some real effort and engineering into in (good insulating gaps on the PCB) but I suspect they opted to buy the cheaper transformer, or it could have been just a freak accident.
It seems like this probably wouldn't have damaged any devices plugged into it unless possibly they arced to ground. It does of course provide an electrocution risk as well as a very large fire risk. This is why it is important for chargers and such to have a ground, if it did (assuming they work similar to here in the USA), it would have tripped the breaker, eliminating the danger and alerting the user to an issue before it became dangerous. I think all chargers should have a ground. A lot of them, even large name brands, do not (applies to both European countries and USA).
Company should be closed down ,all sales stopped on all that don’t pass testing
Brilliant analysis. I remember a colleague who designed a transformer for a product I was working on. One day, I saw him carefully unwinding a transformer. I asked what he was up to. "I validated the samples the company sent us, I'm now validating one of the production transformers they sent us to make sure they are to the same standard". Turns out, production samples and production run parts don't always conform to the same specification 🙂 That was 25 years ago, looks like the same holds true now. Shame, because I agree, it looks like they did a good job on the other parts of the build.
Obviously they don’t hipot test each component.
Thanks Clive. Scarey sh*t and an interesting teardown /analysis. I subscribed after the short (excuse the pun) I watched, about ceramic capacitor failures. I had about three different chargers fail around the same time and got sick of it so I started looking at boards… I ended up suspecting the flat ceramic capacitors on one but have gone no further. Then I bought a new two bay USB hard drive box and promptly found what I consider too much residue on parts of the board between multiple pins! I have not been game to hook it up considering the Tbs of data I could potentially lose! There is just so much low quality electronics that gets into the market.
He's lucky to be alive.
wonder if it had a 3 wire from main plug would the chasse ground have save it from shocking someone?
Nothing probably gets your attention quite like something that is supposed to output 5VDC throwing sparks when contacting the radiator! 😮
Comes with a hand warmer, instant phone charging, adrenaline fueling lethality, and probably a fireworks show as a send off when you do eventually touch it. 10/10 product
AliExpress has good and bad products, the tech ones which are very cheap (65w for stupidly cheap? Yeah, hard pass), but they also have plenty of good ones.
A lot of stuff I use daily I bought from AE and am happy with it.
Think also manufacturers of usb psu.
I looked online there are loads of complaints about that usb psu, think you ort to contact amerzon tell them there selling dangerous goods they could find themselves in a court for selling dangerous goods! Think you ort to contact amerzon tell them there selling dangerous goods be better coming from you as electrical engineer carry more weight!!
Just looked on line loads coments on dangers of swees usb psu!think you ort to tell amerzon of problem, carry more weight coming from you,they amerzon could find themselves in a court for selling dangerous goods!