'Dodgy Type-C USB cable fried my laptop!' Getting hold of USB-C cables can be a pain, but a Google engineer has found one that actually qualifies as dangerous after it broke three pieces of hardware, including a very expensive Pixel Chromebook. Googler Benson Leung has been on a quest to try out the latest USB Type-C cables and find those that aren't up to snuff. …
The Amazon that has a 110-240V charger (for Kindle) with a CE mark but USA pair of blade connectors?
How on earth does ANYTHING with a USA mains plug (only, not interchangeable like some clever travel PSUs) get a CE mark, even if it internally can work on UK electricity?
Oh, it fails massively on EMI (RF interference) when actually charging anything. Perhaps the FCC / CE tests for RFI/EMI were done with no load?
CE is a process of self-certification for the European market.
Anything that directly plugs into a UK socket needs to meet BS standard (can't remember off the top of my head - 6689?)
I've noticed, reading the comments on products, that sellers who might have "questionable" electrically wise kit on Amazon are happy to say CE and "safe" but avoid answering questions re actual electrical standards, and invite the buyer to discuss it off-Amazon.
"How on earth does ANYTHING with a USA mains plug (only, not interchangeable like some clever travel PSUs) get a CE mark, even if it internally can work on UK electricity?"
Probably because in this instance the manufacturer (Chinese no doubt) thinks CE stands for Chinese Export and has probably never heard of Conformité Européenne or chooses to ignore it?
Shaver 2 pin plugs are not USA blades. They are for a power limited transformer isolated sockets. They are based either on Europlug or old UK 5A plug (not the same).
The Blade spacing and shape of Kindle charger with CE mark is USA only. Quite different and narrower spacing than any European plug. There ARE travel adaptor chargers with interchangeable pins. The offending charger isn't a travel type, it's USA flat blade only. It's true that all most shaver outlets have a 110V outlet that will take USA plug. Shaver outlets are NOT the same as as Euro or UK to 2 pin adaptor (of any kind), they are isolated and power limited with a transformer.
"I'm getting rosewood, I'm getting heavy industry fallout, I'm getting the smell of the ones and zeroes escaping in a pall of blue smoke....I'm getting a strange, burning feeling in my legOH SH-"
I think I'll give high power USB a miss till it's matured, somewhat. Thankfully, I'm utterly skint so that's not really a problem at the moment.
Steven "gizza job, mate?" R
But I have bought < €5 HDMI cables, USB, regular, micro and mini USB that are perfectly fine. Expensive ones that were rubbish (One expensive USB cable didn't use twisted pair for data, seemed to be made out of four core Alarm wire cable with no screen.)
Price of cables seems to have no connection to quality. See Monster and Maplin own brand cables pricing.
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I've damaged a 3.5" external HDD by mistakenly using a 19v laptop psu, instead of a 12v PSU. My fault, though I had some ill thoughts towards the world that would use the same physical connector for both.
Luckily, snipping a certain diode off the HDD's PCB got it working again, in theory indefinitely (though I copied the data off pronto). And yeah, had I been more responsible with my back up routine, I wouldn't have needed to go that length.
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Hehe!
It doesn't help that PSUs don't come branded "Seagate" or "WD", which would make reuniting the right PSU to the right gadget easier, but instead all seem to be labelled "Asian Power Supplies"
I think the troublesome 19v PSU came with an Alba LCD TV that someone bought - it was just as useless as it sounds. I either snipped the cable off the PSU, or wrapped it up in red insulation tape, I can't remember!
Yep. Been there done that. Fried a few bits with the wrong PSU. I even triped the whole house the other day when putting in a power connector on some very old caddies with IDE Disks inside (USB2). These had a Bin Plug type Power connector. Another brand of device that used almost identical packaging uad the 12v wired around the other way. Get it wrong and things trip out.
All the new stuff that needs external power gets a stickly label slapped on the device and wrapped around the cable end of the PSU. The different colours allow me to easily detect the right power cable for the device. So far I've not needed more than 6 different colours.
It doesn't help that PSUs don't come branded "Seagate" or "WD", which would make reuniting the right PSU to the right gadget easier, but instead all seem to be labelled "Asian Power Supplies"
Get a Dymo labeller and label the power supply when you unbox it. It'll save your sanity as well as your devices.
It doesn't help that PSUs don't come branded "Seagate" or "WD", which would make reuniting the right PSU to the right gadget easier, but instead all seem to be labelled "Asian Power Supplies"
Probably way too sensible: get out the labelmaker and put a label on the PSU indicating what device it belongs to, the moment you unpack the stuff. Maybe less urgent if both the device and the PSU have clearly-readable power markings and/or unique power plugs, but still useful IMO.
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Re: http://cds.linear.com/docs/en/application-note/an19fc.pdf
What a beatiful document! Other excerpts:
1. Transformer Wired Backwards
Those dots indicate polarity, not smashed flies.
5. Fred’s Inductor (Or Transformer)
Inductors are not like lawn mowers. If you want to
borrow the one out of Fred’s drawer, make sure it’s the
right value for your application
7. Rat’s Nest Wiring
The LT1070 is not a jelly bean op amp that can be wired
up with 2-foot clip leads.
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@Symon:
An inline self-resetting fuse and a reverse-biased diode across the supply (so reversed polarity blows the fuse) won't lose you any efficiency. You do need to be sure the power supply won't just run hot instead of opening the fuse when presented with the forward-biased diode.
Arbitrarily low power loss, all the way to perfectly zero as follows...
Latching (magnetically held) relays, one to isolate and the other wired to reverse polarity. A solar powered supervisory circuit examines and corrects the polarity, before connecting it. The supervisory circuit triggers the system off in the event of a sudden reversal. A parallel diode eats the reverse pulse for the milliseconds needed. Perfect. And ZERO loss.
As that's impractically expensive, just use a low R-on FET. Really low loss.
It's a pretty dumb design decision for a laptop to be powered through the USB socket and NOT put any sort of surge / short-circuit protection in there.
In fact, it's a pretty dumb design decision for a laptop to be powered through the USB socket full stop. A nice example of form-over-function. I suppose Apple can get away with this, as the expected service life of their devices is measured in months, before they con encourage their customers into an upgrade.
>And what is it about your 5 year old Mac that is so magical?
>(sent from my 2010 Sony Vaio Z11- with a removable battery)
VAIOs and Macs have a lot in common. The whole VAIO brand was created by a Japanese fan of the Esslinger design of the Mac, after he created the Playstaion. After Steve Jobs ended the official Mac-clone program, he wanted to make an exception for Sony VAIO kit, since they had been testing OSX on Intel. FireWire. AV editing. Premium price. Proprietary on occasion. Early adoption of Thunderbolt. Former proponents of the PC as 'digital hub'. Etc
- Digital Dreams: The Work of the Sony Design Center ISBN-13: 978-0789302625
- http://www.theverge.com/2014/2/5/5380832/sony-vaio-apple-os-x-steve-jobs-meeting-report
-http://www.cnet.com/uk/news/sony-vaio-z-series-laptop-boasts-external-graphics-and-thunderbolt-tech/
> I suppose Apple can get away with this, as the expected service life of their devices is measured in months.
Can you please supply a link to support your claim? It does seem at odds with every UK Consumer Association report I've read in the last few years. I'm curious if there is anything I've overlooked that would account for your point of view given the data available.
http://www.zdnet.com/article/consumer-reports-notebook-reliability-survey/
http://www.digitaltrends.com/buying-guides/which-laptops-are-the-most-reliable/
http://www.consumerreports.org/cro/laptops/LaptopReliability
The point was not that Apple equipment fails, but that Apple "fails" it by offering newer and shinier in a matter of months. More a comment on Apple's consumers than on Apple. I've found Apple equipment to be solidly built and reliable (68K and Power based, to be sure). My daughter, although not my son, would concur, although she has moved on to Samsung and Microsoft, while he recently bought an iPhone 6.
Anonymous to try to sidestep family friction.
Support for my claim:
In eight years, twelve versions of the iPhone have been released. I'll leave it as an exercise for the reader to count the number of MacBooks there have been, or iPods or iPads, etc. etc.
A significant part of Apple's business model is convincing their customers that they need to make that 'n+1' upgrade.
I was making no comment on the robustness or longevity of the hardware, merely its service life - i.e. how long it will actually be used for.
I even use "disposable" €5 DMM if I'm suspicious of a PSU. Or an old mechanical AVO if it might have more than 250V (I've seen the €5 DMM die with blue flash on the 750V range with 450V DC).
Certainly I'd make a custom jig with a host and slave socket and switchable load as well as switchable signal source and "eye" test data error meter. You can't test cable performance for data with out an expensive test meter as it will either work or not on "real" gear without knowing margin. The power aspect needs measure of voltage drop vs load (a DMM might not reveal the real story) while wiggle cable and plug.
Doesn't sound like proper lab testing.
I can only guess he wasn't testing the manufacturing quality of cables, simply the performance of cables with an expectation of there being no fatal manufacturing defects.
With hindsight I imagine he realises it was a rather misguided idea to simply try another analyser which blew up, caught fire, sank into the swamp, just like the first one.
But he's not the first person to have had a failure and a naive belief it was a one off rather than a systemic fault. As anyone who ever had a second VHS tape chewed up can probably testify.
Many moons ago (a habit I must stop) I popped a £1599 1.6Gbyte brand new hard drive in and it started smoking. It was returned and replaced but while it was away I used the power lead (which came with the drive) to fry another drive. It had the 12 and 0V swapped over!!
I've discovered a lot of random choices on devices that use those round power plugs. A few diodes here and there would save a lot of money - but then I guess ignoring standards is a pathetic attempt to get more.
And yet I have a selection of more than a dozen sleeve-and-tip connectors in a draw (they came with a universal laptop PSU), of every internal and external diameter, some with pins. Engineers had this selection to choose from, yet they still arrived at using the same connector for 12v and 19v.
And yeah, sleeve-type connectors make tracing the polarity tricky, too.
Once these USB-C teething troubles are ironed out, I look forward to the ensuing sanity of powering bigger kit. Just as 5v 0.5A / 1.5A has become convenient for smaller gadgets.
A few diodes here and there would save a lot of money
The problem is that diodes have a voltage drop across them, ~0.7 V for standard Si, ~0.4 for Schottky diodes. That means you have to design for a slightly lower power rail *and* have to have a large enough diode to dissipate the heat if you're taking any significant current.
Usually human error... in the latest adventure of "The Avengers", the superheroes build a time machine... all of them, including Squirrel Girl, a charming young woman who has powers (and proportionate tail length) of a squirrel, and her sidekick Tippy-Toe... who is a squirrel. And is colour blind (despite also being a girl squirrel).
Red-green cable coding mix-up hilarity ensues.
People make mistakes is what I'm saying (and so do squirrels).
But testing the equipment before it leaves the factory would be a welcome courtesy.
Benson's list of leads is here
https://docs.google.com/spreadsheets/d/1wJwqv3rTNmORXz-XJsQaXK1dl8I91V4-eP_sfNVNzbA/htmlview?sle=true#gid=0
Having purchased a Lumia 950XL, which has "fast charging" rather than "quick charging", I have been looking for suitable chargers. I guess I am gonna have to stump up £20 for a USB-C charger. I would have preferred a 3 AMP charger with both USB-A and USB-C ports but thus far they look a tad iffy.
(BTW you cant "fast charge" using USB-A to USB-C)
My personal best (worst?) involved getting a bit too hasty with the wiring of a Teletype(tm) machine. accidentally bypassed the resistor in series with the selector magnets (ask your grandpa). The sparks from the keyboard were impressive, as was the sight of the selector magnets charring as I leaned on the NULL key (no break key) while fumbling madly for the power switch around back.
One I observed (but not my fault) involved an outsourced PCB for a custom PDP-11 peripheral. The designer had confused the specs for Solder and Component side. After a quick bench check for obvious DC issues (jumpers to the filter caps for power), it was placed in the chassis and the system powered up. -12V went into the board's +5 terminal, then out all the common bus lines to torch every board in the system.
Oh, yeah, I forgot the recirculating pump for the hot tub on a house I once bought. The manual (air remote) switch was wired in parallel to a timer that would make sure the water was circulated often enough to stay filtered. Of course, the leads were crossed, so if someone left it running on the manual switch long enough for the 4AM timer to kick in, there would be a dead short across 240V mains. Found by inspection while fixing some other dodgy stuff, not by investigating a loud bang at 4AM.
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