Dangerous Apple Power Adapters? 240
An anonymous reader writes "Even with all these exploding Dell notebooks and other notebook safety problems, Apple has seemed relatively immune. Every once in a while, some odd thing came along, but it seemed like relatively calm waters. Not anymore — Apple's notebook power adapters appear to be the source of some serious safety concerns. Every iBook and PowerBook user should read this and keep a close eye on their adapter — the adapters suffer from very poor design including wires that seem prone to short out and burn and zero short circuit protection."
Re:Blogs = Science? (Score:1, Informative)
Guy is not an EE (Score:5, Informative)
Here's what he says: Meaning, I can short the adapter on the DC side, generate a spark, and repeat again and again without causing the adapter to power off or any circuit breaker/fuse/GFCI outlet to cut the power.
He's expecting the wrong results. Sure, shorting any supply with output capacitors will generate a spark -- that's typical good design. The spark doesn't last long and it isn't indicative of the total energy released.
Now, if his circuit breaker or fuse triggered, I'd be concerned. That means the adapter is shorting out the mains voltage -- very bad, very dangerous. But, it apparently is not. It's good that this doesn't happen, but the guy seems to think it should. And a GFCI wouldn't trigger due to a hot-neutral short [wikipedia.org] -- he would have to throw the adapter in a bathtub to have a chance of it tripping.
I'm not saying there are no problems with the adapter, but his assertion is unsupported by his evidence. I suspect that the adapter has an internal short-circuit protection that kicks in milliseconds after the spark is seen. He would need to use a current meter to detect if the circuit exists.
(why, yes, I'm an electrical engineer)
Re:Missing last line... (Score:4, Informative)
Damn, this pisses me off. The correct tag is "!fud", RTFM. [slashdot.org]
Re:Here are some technical details: (Score:5, Informative)
Also of note, the "ufo" power adapters that shipped originally on the ibook G3s are much much worse. They are known for failure where the DC cord meets the computer plug and where the AC cord meets the connector that plugs into the pack. We have replaced many of them for failure at one of these two points. Though for all the macs I've worked on, I have yet to encounter a single apple pack that caught fire. This sounds like an isolated incident and someone trying to make a whole lot of noise, stomping about and shouting "defect, recall, save me!"
Given 50,000 production units of electronics, a couple of them are going to be bad. There is no escaping that. And yes, one of them might burn down your house. But a meteor might hit it first, and has roughly the same odds, OP needs to get over it.
Though I don't deny he needs to post about it, because this is how you find out about real issues. Now if we saw a dozen "me too" followups immediately we might want to look into this more, but right now we just have a blowhard.
Re:Fuss about nothing - not just apple laptops. (Score:3, Informative)
So I tore it apart to repair/replace it, and I was amazed that when I removed the plastic jacket of the cord, the outer braid (the ground conductor) of the cord fell to the desk in a pile of a milllion little 3mm long pieces of copper strand. The braid had just shattered from repeated bending, and when I just shook the cord there was NO copper at all left for a 1" span of the cord, it was all just in a pile on the desk. Sort of like when you take a coat hanger and bend it enough it breaks. Same thing happens to these adapters.
Moreso, the white insulating material between the braid and the inner (power) conductor was cracked all the way around in three places. If any of the bits of copper had found their way into any of these cracks I suppose I would have had the same problem the poster did.
In that case though the design was defective... they put that huge balun 1" down the cord from the computer jack, separated by a 3mm thick wire, what did they expect? They don't do that with any of the new cables thankfully.
Re:Here are some technical details: (Score:3, Informative)
That's true. I think it's something to do cracks or holes in the plastic. In every UFO PS at work, they'd die at the DC plug, and you can clearly see that the copper wire had oxidized and turned green.
FWIW... (Score:3, Informative)
I cut and stripped the wire with a pair of fingernail clippers, twisted it back together, and wrapped it back up with the duct tape. Several months ago the duct tape came loose and the wire shorted again. I re-spliced it, and wrapped it with Scotch tape, which was all I had on hand at the time. About a month ago the Scotch tape started coming off (as I had known it would), so I retaped it with white electrical tape.
I do freelance IT work, and haul my iBook everywhere. My power cord gets unplugged, wound up, stuffed into a backpack, unwound and plugged in somewhere else pretty frequently. Even when completely shorted out, all it did was make a clicking noise. The adapter brick can get pretty warm, especially when it's not well ventilated, but not uncomfortably so.
Please keep in mind that most of us never have a problem, even in unusual circumstances.
Re:3rd party power adapter (Score:4, Informative)
Ah. Another Dvorak-In-Training article. (Score:3, Informative)
Re:Why America? (Score:1, Informative)
Actually if an apple adapter is anything like any other adapter for notebooks then it _is_ the same adapter as you can plug them in in anything between 100 - 250 Volts.
And oh btw. it's always a good idea to have a spare adapter, if you can afford one.
--
Wil
Re:Apple has ALWAYS (Score:4, Informative)
Networking over serial I/O was a reasonable choice for the time. Zilog had a chip that would do serial I/O at 230 kbps and Ethernet hardware was still very expensive.
Re:Here are some technical details: (Score:3, Informative)
But yes as I said, Apple's power adapters are notorious for poor strain relief performance and I'm sure this leads to premature failure, but if you allow the damage to progress to the point of catching fire then you are really out of it. While there is not a problem in general with most power packs, it is a problem with laptop power packs in general because they are plugged and unplugged sometimes several times a day and the increased use leads to much faster wear and tear. I haven't seen any proof however that better materials are available that are not being used, so it's hard to condemn them just yet. Apple's "plugs into wall" design is very convenient and saves us a lot of cord to deal with, but also causes the user to pull the power cord at a sharp angle to the adapter, and this too probably contributes to premature failure. The cord is actually shorter than most laptop packs also, which probably makes matters worse trying to stretch the cord to the nearest table.
Re:Apple adapter puts nasty load on inverters (Score:5, Informative)
It's to do with the current waveform. Any switchmode supply tends to have a very spiky current load, as it switches on an off to keep the output voltage stable. A cheap switcher, if it's lightly loaded, will draw huge spikes of current only in the early part of each half-cycle - so it's current load looks just like one or two noise spikes, which get absorbed by any output filtering &/or ignored the protection circuitry in the source UPS/inverter.
A better switcher, on the other hand, will spread that current draw over the each half-cycle - so it's current load looks like a continuous noise hash to the supply. Enough hash to get back past any output filtering on the UPS / inverter and trigger the protection circuitry.
Hence the reason any decent UPS or inverter has specific warnings and / or deratings when used with switchmode loads.
(Yup, that's a simplified explanation - but it's also basically correct...)
In your case, it would probably work better with a smaller inverter, or a cheaper & nastier one without such good protection circuitry
IMPORTANT: A solution already in the box. (Score:3, Informative)
However, I decided to inspect the adapter, detached the A/C plug, which snaps on and off the corner of the adapter, and was horrified to notice it was thoroughly charred on the inside. Then, I vaguely recalled that a power cord came with the iBook, in the box. This is what I'm talking about: http://www.shentech.com/aprepog4ib65.html [shentech.com]
To my great relief, the new power cord snapped neatly into the corner slot of the adapter, and ran smoothly. It was the detachable A/C plug that was defective, not the adapter itself. Now, not only could we throw the defective plug where it belongs (in the trash), we also had made our device safe, as well as doubled the length of the cord, and saved ourselves $80.00 to boot! My wife and I were happy campers that day.
So, if you have an Apple laptop, check this out for yourselves and I'm sure it will allow you to solve/avoid this exact problem, and even if it's not malfunctioning yet, do it now, no use putting your expensive computer at risk. Also, even if you've misplaced the box and/or cannot find the power cord, buy that instead, as it's price starts at around $10.00, saving you quite a bit of cash in the process.
Re:A little bit of fanboyism? (Score:1, Informative)
Let's repeat that, the manufacturer *lied* about the specs of the batteries.
An incident during product testing uncovered the lie.
Apple replaced *all* of the batteries with NiMH versions *before* the laptops were sold.