Dodgy usb plug

[Maker]

I dropped something on this knockoff Apple charger this morning, saw a bit of a spark through the case and thought "Oops that was close", then looked around and realised I'd tripped the fuse, it turns out the 32A MCB and RCD had both gone, never known that to happen before. My brother says its tripped the RCD before so I decided it was knackered and pulled it apart...



Note the scotch marks on the case, earth pin and silver rectangular "component".

That "component" fell straight outout, no leads on it and it's a bit heavy to be a capacitor or anything, because it's actually just a useless block of steel, presumably to give it a bit more weight for the impression of quality.





It sits very close to the live terminal on the PCB, possibly touching it but not touching anything else so it shouldn't matter, until the case gets a knock and it also touches the back of the otherwise unconnected earth pin.

Moral of the story, don't buy cheap crap chargers, you wouldn't get that with an Anker plug.

 

[eddie49]

There used to be a "make-weight" sometimes added to a box of chocolates, but they were rather tasty pure chocolate, not scrap steel.
Have you worked out how the circuit works? I can see 4 capacitors and a transformer, but no rectifier.

 

[Spuddevans]

Big Clive on Youtube has done a few teardowns of cheap/fake chargers. When you see how poor quality they are, and also how dangerous some are, it really makes sense to pay a bit more to get a genuine charger. Especially if you've got a £5-800.00 phone, or even perhaps close to a £1000.00 tablet or even more expensive laptop, paying even £100 for a genuine laptop charger, or £30.00 for a phone charger is not so big a price to pay than potentially frying your uber-expensive device.
Tim

 

[Onoff]

you wouldn't get that with an Anker plug.

I had a genuine Anker 10000mAH power pack. I was charging it from an again genuine MK, usb wall socket. The power pack got red hot to the point of smoking and died. Luckily I noticed it, disconnected it and lobbed it outside.

I assume both products were genuine having come from reputable well known retailers.

Saying that I think this is the 2nd MK usb wall socket to have died. I wonder if it was because it can only offer 3.1A and we were likely charging 2 high current devices at any one time?

Got a Click one to fit sometime.

 

[Maker]

There used to be a "make-weight" sometimes added to a box of chocolates, but they were rather tasty pure chocolate, not scrap steel.
Have you worked out how the circuit works? I can see 4 capacitors and a transformer, but no rectifier.

I'm away for the rest of the week but if no one's binned it by the time I'm home I'll trace it out and see what's going on. I don't think there's any diodes on the back of the board so maybe there's some clever trick to do without them, or maybe I just wasn't paying attention.

 

[not done it yet]

My brother says its tripped the RCD before

I think you need to teach your brother that those trips are caused by something - that item should have been dumped at that point. Dangerous to ignore the warning signs.

 

[Domdom]

A decent genuine Apple charger is £19. Why use knock off?

Read some of the stories about knock off chargers catching fire, damaging equipment and so on, you really wouldn't want to use them at all. Mrs DomDom bought a knock off charger for her mini hedge trimmer (Bosch) from eBay cost she thought £40 for a genuine one was expensive. 4 charges off it and now the clippers are dead with fried charge circuits.

This one is 20 watts, charges an iPhone XS Max in about 45 minutes. (They do go bigger as well) Note that all Apple chargers now use the USB-3 cables.

Buy 20W USB-C Power Adapter

The Apple 20W USB-C Power Adapter offers fast, efficient charging for the new iPad Pro models. Use it at home, in the office or on the go.

www.apple.com

 

[AKN]

Some of the genuine Apple ones had problems here's the recall info.

Apple three-prong AC wall plug adaptor Recall | Electrical Safety First

The Apple three-prong AC wall plug adaptor has been recalled. This product may have safety issues or dangerous defects.

www.electricalsafetyfirst.org.uk

I've got quite a few of the "affected" ones none have failed.

 

[Maker]

My brother says its tripped the RCD before

I think you need to teach your brother that those trips are caused by something - that item should have been dumped at that point. Dangerous to ignore the warning signs.

He thought it was a coincidence, it hadn't tripped it before or since.

A decent genuine Apple charger is £19. Why use knock off?

I don't even know why he bought it, we've got dozens of them kicking around from old phones, tablets, etc.

Totally agree about fast charging too, this POS is (was) 5 watt, that wouldn't fully recharge my phone overnight, I think it accepts up to 30 watts for fast charging.

 

[Domdom]

Some of the genuine Apple ones had problems here's the recall info.

Apple three-prong AC wall plug adaptor Recall | Electrical Safety First

The Apple three-prong AC wall plug adaptor has been recalled. This product may have safety issues or dangerous defects.

www.electricalsafetyfirst.org.uk

I've got quite a few of the "affected" ones none have failed.

At least cr-Apple have the decency to advise when there is a problem. Yes, the "genuine" ones are probably still made in the Far East, but with higher levels of QC than the unbranded eBay rubbish. Don't recall me ever having seen a recall for eBay items either.

 

[Domdom]

Totally agree about fast charging too, this POS is (was) 5 watt, that wouldn't fully recharge my phone overnight, I think it accepts up to 30 watts for fast charging.

Even my Juice wireless charging pad manages to charge my iPhone in about 2 hours and that’s 10 watts.

 

[Maker]

Have you worked out how the circuit works? I can see 4 capacitors and a transformer, but no rectifier.

Back side of the board, bridge rectifier is bottom left, Schottky diode in the middle, top right is a "Poweric PI751", can't find a datasheet so not sure what it does.

 

[Kram]

Poweric PI751", can't find a datasheet so not sure what it does.

The live is rectified straight off, so its feeding DC to the transformer using that IC as a switch mode chopper.
Id like to see much better seperation on the pcb but they do have some air gaps.

 

[Seadog]

I dropped something on this knockoff Apple charger this morning, saw a bit of a spark through the case and thought "Oops that was close", then looked around and realised I'd tripped the fuse, it turns out the 32A MCB and RCD had both gone, never known that to happen before. My brother says its tripped the RCD before so I decided it was knackered and pulled it apart...

View attachment 353368

Note the scotch marks on the case, earth pin and silver rectangular "component".

That "component" fell straight outout, no leads on it and it's a bit heavy to be a capacitor or anything, because it's actually just a useless block of steel, presumably to give it a bit more weight for the impression of quality.

View attachment 353369
View attachment 353370
View attachment 353371

It sits very close to the live terminal on the PCB, possibly touching it but not touching anything else so it shouldn't matter, until the case gets a knock and it also touches the back of the otherwise unconnected earth pin.

Moral of the story, don't buy cheap crap chargers, you wouldn't get that with an Anker plug.

Send it to Big Clive