Slashdot Mirror
Dell Laptops Have Shocking New Problem
dapsychous writes "A friend of one of my coworkers has noticed a problem in Dell notebook computers (also covered in this engadget article about a problem that has been popping up lately in Dell 17" notebook computers). It seems that these computers are putting out between 19 and 139 (65 according to article, 139 according to him) volts of AC power as measured from any chassis screw vs. earth ground. This has led to several problems including fried ram, blown video circuits, and a stout zap on his left hand.
According to him, Dell has tried to keep him quiet about the problem and has even gone so far as to have him banned from a few websites, and threatened him with legal action if he tells people about the problem."
He bought a Dell!
The opposite of progress is congress
I'm running an E1705 (manufactured in May of last year) and I'm not seeing this. Maybe his unit just sucks at grounding. (They're called manufacturing defects for a reason, and last I checked, they're covered by warranty and by law.)
Viable Slashdot alternatives: https://pipedot.org/ and http://soylentnews.org/
shock...
I'm on one of those right now. i will be calling Dell ASAP to see if I am affected.
*sigh*, Is there not a company we can trust anymore?
"No freeman shall ever be debarred the use of arms." -- Thomas Jefferson
the weather? Dry air == lots of static electricity. I ground myself before I touch anything electronic at this time of year.
Best Slashdot Co
...it doesn't get much more reliable than that!
"Ask not what your country can do for you." --John F. Kennedy
I wonder if Dell has something to do with this...
if a power supply doesn't do it, pop out the drive and put in a new chassis.
is Dell that bad at support nowadays? or is it just another "call me Bob" who has no clue who he's working for this month overseas and doesn't care?
if this is supposed to be a new economy, how come they still want my old fashioned money?
Dell's new marketing campaign should be: Dell: our computers are elecrifying!
The original generic sig.
Okay, not really, but shouldn't happen in the UK. According to the article:
"The latest word is that VG's own problems were solved by springing for a three-pronged grounded power adapter"
You can't get a non-earthed plug in the UK, the earth pin is physically required to open the plug socket. This can be a dummy pin, but you're only able to do that if the unit itself is double-insulated.
long ago, i had an AST "tower" (pentium II, or was it I? So long ago.. ;o) that zapped me mildly. I measured from chassis to ground a nice 40 VAC. But only when the network card (coax) was in it. o.O
The "Civilized World" jumped the shark ca. 1973.
Don't they run off a low voltage DC supply? What bit of the hardware inside would be upping the voltage to that sort of level? I can't think of anything offhand. Anyone know?
My EE is very fuzzy nowadays, but 65 volts AC root-mean-squared would indicate a higher voltage peak-to-peak. But not as high as 139 volts peak-to-peak. I get 65*2*sqrt(2)=91, but forget if that's even the right way to calculate it. Maybe the 139 volts is a high-water-mark sort of non-repeatable measurement?
[
Sounds like someone broke their labtop and is pissed that Dell won't replace it for free.
The forum post also mentions "*Update* The following problem appears to be solved by getting a 3 pronged grounded adapter fro Dell."
The big question why didn't it come with one by default?
I sometimes feel a small current when I'm touching the bottom of my Dell 6400/E1505 too... and I thought I was the crazy one...
Why are individual gripes making it to /.? What is the statistical significance of this observation?
/.
A single manufacuring defect (if that is the problem) isn't worthy of
Also, did the "friend" modify the laptop at all? Perhaps disassemble it or otherwise "improve" it?
We've all gotten a lemon at one time or the other.
Stop griping... get a life.
The articles are rather light on details, but I'm wondering if some of these people are using their laptops on a couch and sliding a bit when they sit down? I've had an Inspiron 6000 for a bit over a year now and I've learned in the winter to be careful to set it aside when I'm getting on or off of the couch, lest the static electricity give me a nice zap.
The fact that he's measuring AC (which is very surprising since the laptops don't have any ready access to AC outside of the power brick AFAIK) make it less likely though.
I read the internet for the articles.
threatened him with legal action if he tells people about the problem.
Why bother? they just have to tell him that, to fix the problem, he just has to touch these two tiny screws there with both hands and power on the machine. Problem solved!
Seriously though: where is 130V coming from (or is even used) in a laptop? I was under the impression that there's nothing high voltage in there, save for the LCD backlight perhaps?. So perhaps there's a chance that this is all a bunch of crap from some dude who's pissed off at Dell for some reason (and god knows there are plenty of reasons).
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
... you're getting a defribulator!
Honestly, though. A friend of a coworker is hardly the most reliable source. This doesn't seem to be a widespread problem, seeing as the only mention of it thus far is a single thread with no replies on a message board.
When I am king, you will be first against the wall
With your opinion which is of no consequence at all
My Macbook has the same problem: whenever it pulls in a lot of current, I get an electrical shock when touching the head of one of the screws. I'm not alone with this problem, there are several threads on the Mac support forums about this, e.g. this one. Of course there's no official statement from Apple :-(
My work laptop (an inspiron 6400) has this problem.
I've been shocked a few times and have gotten memory parity bluescreens at least twice.
HD has bad sectors too.
Was already going to call in a support request this weekend when I have time to have the damn thing replaced.
Have a look at the comments on the Engadget story - there are literally dozens of people saying "yeah, me too, I get shocks off my laptop all the time" - but they just ignore it. How stupid are these people? Are they hoping for a Darwin award? If you're getting a 60 volt shock that hurts today you might be gettng a 230 volt shock tomorrow *which might very well kill you*. OK, you're fairly young and like to think that you're fit and healthy, but are you *certain* that you don't have some latent heart defect?
Honestly, if you are getting *any electric shock at all* (apart from a bit of static and it's easy to tell the difference), GET IT SORTED BEFORE IT KILLS YOU.
i will be calling Dell ASAP to see if I am affected.
Um, and why would you expect them to give you a straight answer? They'll probably just play dumb and say they've never heard of the problem. (Which will probably be true, at least for the drone you'll be talking to.)
Get out a voltmeter and test it; that would seem to be the easiest solution, and less likely to lie to your face than some Customer Service rep. Probably faster, too.
Until a problem like this becomes terribly public -- and by this I mean more public than just being covered on some technology websites -- I suspect Dell will deny it, except in cases where people absolutely insist that they have a problem, and demand a replacement. In those cases, they'll get a replacement machine just to shut them up.
So I'd just get out the old multimeter, measure the AC voltage from one of the chassis screws to the nearest good ground, and if it's more than a few millivolts, call Dell and tell (not ask) them that you need a replacement unit.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Do they use Sony Batteries Too?
Let the corny puns begin!
Thank goodness I resisted buying a Dell!
My parents had a problem with their garage door opener. Turns out, if you were in your socks (or less, depending on the age of the kids running around) you could get a pretty good jolt from the garage door RAILS coming down the side of the opening.
Tested with a volt meter, got anywhere between 60-130v rail-to-ground. And it was intermittent.
Upon unplugging the garage door opener, the voltage went to nothing. So, I asked him "Who wired that outlet?" He responded that he had wired the outlet, and was sure that there was a ground wire hooked up. So, I took the volt meter and hooked from ground on the outlet to ground on the ground strap of the breaker box. No connection.
Once he re-wired the socket, we had no further issues with the door rails. However, it's funny to mention that he had two seperate electricians out, and they couldn't figure out why there would be voltage on the rails. I'm guessing they were making the same assumption that my father did - that the ground in the box was actually hooked up properly.
Now, the guy in the blurb may have a good case against Dell, but I'd be curious to see where the laptop is being plugged in to, and if there's any relevance to shocks at that point. I know my house was built a long long time ago (1951) and the upstairs, while someone put in grounded outlets, it doesn't physically have the ground hooked up - due to the wiring used at the time of it being built.
Karnal
This guy is measuring a voltage that is higher than our main voltage by twenty volts. Ten volts is plausible but twenty????
Ooo man the floppy drive is broken. No wait. The computer is just upside down.
For a while, I thought I had a similar problem with both my new Dell laptop, and an old dumpster-diver I had before that. I was getting shocked occasionally when I touched the machines. I initially blamed it on poorly grounded wiring in my house (a rental), until I realized that the problem was electro-static discharge build up from sitting on my Durapella couch.
I worked it out recently when cold winter temperatures drove the humidity way down. Whenever I got up from the couch I would feel the charge build up, then I would inadvertently discharge myself of a light switch, a metal corner post in the drywall, or worse, on some home electronics. After I accidentally blew out the panel of buttons on a DVD player, I did some experiments. By rubbing my hand on the couch cushions for a few seconds, then using a piece of metal held in my hand (less painful that way) to discharge myself to ground, I found I could jump a spark 2 cm or more. Sometimes, I can get multiple sparks on one charge.
It's kind of cool, if you know to expect it. And, the remote still works for the DVD player...
--WH--
If my Dell laptop doesn't explode in a shower of sparks and fire it'll instead shock me? Yeah, that makes me want to run out and buy a Dell..
I'll stick with my old Compaq...
Yes Francis, the world has gone crazy.
About 5 years ago, I was doing IT work, and had to support a bunch of Dell laptops my employed had purchased prior to my starting there. the one in question was an Inspiron, don't remember the model number, but it was probably a P3-800 or so.
Anyway, the user was complaining about power issues with the laptop - things like it sudenly shutting down, starting up by itself and running the battery down, etc. Then out of the blue, she said, "and it's shocked me a couple of times." Like that's expected behavior.
I was somewhat skeptical about this, and figured it was a static problem or something unrelated but found out the harsh truth while I was on the support call with Dell. They had me do the usual bonehead stuff like do a hard reset, update the BIOS, remove/replace the battery, etc. I was typing on it and got zapped on the thumb with a serious shock. That's when I noticed the little scorch mark next to the right trackpad button. Looking down through the gap between the button and the case, I could see a little bit of metal from whatever was underneath. Enough charge was building up in there to arc to my hand, which can't be good.
The Dell support guy heard me yelp when I got shocked and asked me if everything was OK. I told him I just got a nasty shock from the laptop and he said, "can you hold for a minute please?"
I waited for about 2 minutes, and then some other guy came on the phone and said that they were sending out a replacement overnight and that I should return the other one right away. The replacement was a top-of-the-line Inspiron for the time, quite a step up from the one that zapped me. I figured it was a pretty good response.
So I issued the user a new Thinkpad from our closet and kept the nice Dell for myself. It worked out for everybody.
On an older Inspiron 8600 laptop. I contacted Dell Warranty Support and my laptop was replaced with a newer E1505 core duo model within a week.
Normally I would have been happy, but the new system had inferior graphics and disk drive, and was incompatable with the upgraded RAM in the old system. Dell would not reconcile the issues, and just had their tech support deny my claims.
My laptop shocks me all the time. I thought this was a feature to keep me awake on long flights.
Perhaps is an as yet unannounced joint venture "feature" that Dell is not allowed to disclose, yet?
2 16219
http://yro.slashdot.org/article.pl?sid=07/02/04/2
"Dell has tried to keep him quiet about the problem and has even gone so far as to have him banned from a few websites, and threatened him with legal action if he tells people about the problem."
On what grounds would this be a valid case? Once you sell something to someone that they own (not license), you cannot tell them what they can and cannot do with it so long as you do not cross any other lines and violate someone's privacy (which is why I suppose selling stuff you bought at auction from a storage company is illegal -- although I think most of what those guys did was OK, and the judge overreached). So this guy has every right to say "My computer shocks me, here's what kind of machine it is" because it's not slander, it's the truth.
Seems to me like this guy can file under anti-SLAPP rules, can't he? This company is trying to shut up someone who is exposing their mistakes -- and yes, it is a valid complaint (why wasn't he given a grounded power supply when it is known that failing to ground electronic devices can shock users?) and yes he has the right to be publicly heard if he wishes to. No one has the right to not be offended by what he has to say.
i am a soviet space shuttle
Last time I was at my accountants, I got zapped by his new Dell Laptop. Maybe just luck.
JohnE
jobbank.com - Search jobs, post resume,
Don't buy a DELL!!! my gateway computer cost me $899, it's got a 120 GB HD, 1 gig ddr2, 15.4 ultrabright widescreen, 128 megs dedicated video and more. I've had no problems at all! or buy a mac!!
It may come as total shock to you, but I know plenty of people who are ready to scream "get a DELL! I've never had problems with it" with as much enthusiasm as you do for your Gateway box, and none of these testimonies prove anything at all about the quality of Dell or Gateway products.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
One thing really important to understand about grounding is that electricity finds the path of least resistance to complete a circuit. (pun intended). My guess is that he probably is working barefoot on a concrete floor.
Also, I don't see why the transformer is not isolating the high voltage between the AC and the Notebook.
Europeans have to be more careful with their AC. 220 volts breaks skin resistance much faster than 110V. Remember kids- amperage kills, but voltage gets the party started!
A long time ago, I noticed some similar problems with equipment powered off a two-wire power feed (actually a monitor). It could build up quite a voltage relative to earth (up to 90v) and possibly to other equipment. This wasn't a PSU fault and was down to some kind of leakage current in the switched mode power supply when it was switched on. If the current stayed in the microamp range, (which it did) then apparently this wasn't a problem. However you really didn't want to connect equipment together (even a BNC video connector) after switching on. As has been noted, modern stuff can be fried by this kind of current. Easily.
Of course, you can preconnect everything but then you have a lovely problem chasing mains hum on the audio. If you don't then you get a slight tingle (as being reported on the Dells).
See my journal, I write things there
Whenever this happens to my Dell, I put it in my microwave and run it for a few minutes. Dries out any moisture that sometimes accumulates inside.
He needs to have a good ground. He's using the metal case of another PC as ground so he might just as well be measuring the voltage off the PC case.
People, people: If you can't *touch* the computer, then you can't install anything bad. Or even turn it on.
Come see the shockingly effective new Total Security (TM), now in microSoft Windows Vistzzzzzzzzzzzttttttttttttt.............
that you get from shuffling on the carpet and then grounding through someone's nose are on the order of thousands of volts. The numbers in the article are useless unless there is an appreciable current flowing.
Also, the guy in question appears to be using non-grounded plugs and sockets. That's asking for it in my book.
I can assure you, the best way to get rid of dragons is to have one of your own.
The same problem exists with this laptop. They would not
take it back (Toshiba Sattelite 17"). Yes it was out of warranty.
Is this due to the power 'leaking' or is this a case of the notebooks been so fast they need the power?
I guess this is due to the race to make the fatest notebooks and not revise any sort of means of quality control and forward planning.
This surprises me a little, I haven't seen much of Dell's new stuff, but all of the Pentium 2 class Dell notebooks we have and their P2 class Optiplex desktops have been utterfly reliable machines.
I guess their standards have dropped severely.
Please read and mod up the parent -- provides useful explanation/answer to question.
I am not a crackpot.
I bought a Inspiron E1505 at the end of November. I have this same issue. I have not contacted Dell yet, because I live in Minnesota, on the humidity is so low, I was not sure if that was the issue. I get shocked when I touch the screws. I sorta hurts. Well, now that I know I am not the only one, I will be contacting Dell support tonight.
It would be interesting to see if the DC plug has some leakage to the third wire ground while it is unplugged. It would be useful to either look at voltage on the notebook screws with a scope or otherwise compare the frequency to 60 Hz or determine if its more likely leakage from an inverter within the notebook. I would guess a poor design of the adapter with a two prong plug. Hopefully only very small currents would be available. It might also be advisable to test the wiring of the outlet that it's plugged into.
Dell was from all the Porn I was DL'ing..
sounds like a standard "Your stuff sucks, I going to sue you, and your little dog too..." "Thats nice sir. You wouldn't have invalidated your warranty by making any modifications to this?" "Errmm, thats not the point, I'm going to tell everyone on the internet that you suck!!!!" "you are aware that would constitute slander sir?" "Aaarrghh" ###SLAM!!!!###
Funny, the junk in the article about Dell wanting to shut him up, blah blah blah, isn't mentioned in the article in the link.
As well as the problem already being solved -- his electrical system is fucked. Therefore, the ground adapter fixed it for him.
SO, why is this front page on Slashdot?
"Champagne for my real friends - and real pain for my sham friends!" http://ericblade.postalboard.com/
The article is vague. It's not even clear if the problem occurs when the laptop is not plugged into the charger. The power supply for some backlights can produce over 100v, so there is a potential shock source even on battery power.
If the problem is related to the charger power supply, that's a clear safety hazard. Check for a UL logo, and go to the UL web site to check on whether the power supply actually has approval. If the power supply is made in China, it must have a hologram UL sticker with the UL approval number. There are power supplies out there with forged UL approvals, and UL is trying to crack down. (Those are the power supplies that fail in power supply tests on PC websites. UL tests them loaded up to their rated value and runs them for hours at full load, so the UL logo means it really can deliver whatever power it's supposed to deliver.)
Right - Solved with an adapter.
That means its fine when its plugged in.
What about when its not plugged in?
I once played a pinball game that has hooked up to a few power strips that had a bad ground in them and I got shock form the medal lock down bar.
i was recently sent to a class that used Dell Laptops(i for get the model) and each time i would sit down and beguin to work, i'd get shocked from the laptop.
Michael Dell doesn't fuck around does he!!!!
Acting stupid isn't much fun when there's someone around who knows better
I just measured 36.8VAC @ 60Hz between a chassis screw and plug ground on a Dell Inspiron 15" Latitude D820. Perhaps I'll put it on the scope after lunch. I wonder if it will grill my sandwich?
I just measured the voltage on my Dell M90. It was 3.2 millivolts. Probably ghost voltage.
Harmless...
I just checked all the Dell laptops our company owns, about 10 of them (E1505 and E1705 models). All of them are producing around 3-5 Volts of AC off the screws. In fact the one producing the highest voltage is currently on a service call as the system has stopped working.
I am currently in contact with Dell about this issue and I am being informed they are letting the engineers know of the issue and hope to have a resolution soon.
The funniest thing I have read regarding this was a post in notebookforums from aindfan:
"I took my E1705 up to the Senior Design EE lab here. The two seniors that were there glanced over at my oscilloscope and realized what was going on, most likely assuming that I did not ground properly. When we took it over to the new, more advanced scope, the measurements reported were of a 60Hz periodic function with a peak-to-peak voltage of ~150V.
Being curious EE's, the next natural step that the seniors suggested was to see if we could pull any current out of the screws. A few moments later, we had a circuit with a laptop screw connecting to an LED in series with a 1K Ohm resistor connected to the ground node of a power supply (connected directly to the ground of a wall socket). I am happy to report that the LED turned on and there was a measured current of about 1.4 (mille or micro, I forget which) Amps flowing from the screw to the resistor.
Remember, folks, there will never be current flowing out of the laptop without a load attached to the screws. So don't hook up any 1 Ohm resistors if this is happening to your laptop, you might fry a few things (due to the large current, remember V=IR).
I'm opening up a Dell chat now to see about getting this resolved.
Thanks for starting this thread ViriiGuy. It was quite interesting to play around with the testing for this.
EDIT: When I asked the dell chat support tech if she could send a 3 pronged power adapter (after I explained the issue), she replied "I cannot do that.""
Good stuff.
"Real knowledge is to know the extent of one's ignorance" -Confucius
I read this as 65 Stallmans per 91 file sharers :)
My brother has a Dell Inspiron 6000 (I do too), his is 6 months older than mine and he had a problem with his laptop where the ac adapter overheated then he got a new one and that one overheated and it overheated his laptop and Dell didn't want to do anything about it. I am already starting to see a problem with my laptop doing the same. My brother had someone figure out a way to repair it but it cost a bundle. I do not want Dell to get away with this, because people around the world are going to be having these problems and no one is speaking up.
The Latitude D620 laptop, while charging on the Dell supplied non-grounded AC adapter gives -5VDC with reference to ground off of any exposed metal. The paint on the aluminum lid wears off, so if you grab the lid while it's plugged in you get a small shock. however if you use the grounded adapter, supplied with the older D600's and the Latitude D-Dock, the charge is grounded out and you get no shock. At my university we all have school supplied D620's and they all have this unpleasant surprise, the on-campus repair facility says this is within safe limits....
When I use my Dell M60 (3 years old), and have my hand touch the Dell at the same time as my other hand or a palm touches a metal table or my Apple MacBook Pro, I get a zap that feels like what used to be between 50 volt batteries.
I could measure the voltage, but that wouldn't tell me any more info than I already have.
I do NOT intend to buy another Dell, no matter what Dell says. I can use the MacBook Pro for all my OS needs.
I was checking out a similar problem with a major-us-brand of AV receiver. I was able to meter 70VAC between the chassis of the receiver and the same manufacturer's not-yet-connected DVD player.
However, when trying to get some current to flow, I couldn't get the thing to send more than a few microamperes. This ain't gonna fry anything...
We started punishing people who abuse the law?
No comment on the current story, so it's a somewhat offtopic rant. But, with all this recent obsession with "crime and punishment" the west seems to have developed lately, perhaps some of it is rubbing off on me.
I think it's high time we started to get tough on people who abuse to law to conduct legal assault on innocent people. Whether you use a lawyer, a can of spray paint, or a molotov cocktail should make no difference. If you harm someone who is innocent, you should be punished.
A government is a body of people notably ungoverned - AC
with a good slashdotting. That'll work. In fact it did.
What?
They also sell socket adapters that do this.
"The following problem appears to be solved by getting a 3 pronged grounded adapter fro Dell."
That's a direct quote. Insert your own "m".
What?
Power is measured in watts (or horsepower or electron-volts/second) not volts.
Only his tendency toward a dazed stupor prevented him from screaming aloud.
Wierd question: what if there's a break in the ring of a ring main? All outlets would still be powered by one side of the ring, but current capacity would drop by 1/2 (unless you're using wire rated for the full 30A, in which case, what's the point of having a ring main?!)
-b.
I bought a new Dell 20" monitor in November. After delivery I thought it looked bad for such a well reviewed model. I found out Dell had swapped the well regarded Phillips S-IPS type panel for a lesser Samsung S-PVA type panel. People who found out about this switch and went to the Dell forum to ask questions were censored out. A thread about this problem was started in a hardware forum and it now has 790 posts and 55,000 views: http://www.hardforum.com/showthread.php?t=1111100 I returned my monitor in early Dec. I still can't get my money back from Dell though even though they don't dispute the credit even they say they owe me. Between the service rep on the phone and accounting there is some disconnect. Fair to say that after weeks of talking to Dell serivce and 2 dozen "case numbers" I think things are a real mess over there.
I've wondered about this before...
Could something like this happen if your electrical outlet had hot and neutral reversed?
I'm fairly certain that the right type of transformer failure in a power supply brick can cause this too.
I can not get to either referenced link right now so I am making a few assumptions.
How is AC voltage getting to the laptop? The power converter should be sending nothing but 12-21VDC. It has to be the power converter or even a faulty wired outlet with a bad ground [note 1]. Meaning the voltage between the positive terminal and the negative terminal of the power adapter is low 12-21VDC in relation to each other but they are riding some type of AC voltage with respect to the reference ground. Technically this would not be a problem but as soon as something chassis related touches ground, you have an alternate path for current and if it is really the noted 20 or more volts AC, you will blow things up. Hooking up an oscilloscope from chassis ground to common ground would give more details as to the actual cause. Probably a bad reference inside the device to common ground caused by either a bad capacitor/inductor or a bad ground wire.
I've seen similar problems in some Compaq and IBM laptops in the past. Nothing physically shocking but many on board NICs blown out because the cable provides another different path this current to flow. Compaq came on site and did a field change to several hundred of our laptops, IBM did nothing but keep repairing them under warranty.
In summary.. I think it is the power converter or a bad ground in the outlet because it should not be passing DC riding on some AC wave to the laptop and the laptop itself does not generate its own AC power internally.
[1] I had a faulty home outlet before and it blew up components in my computer (noise, smoke, pieces of chips flying etc..). I connected up my printer via a LPT cable to my computer and as soon as I plugged my printer into the wall... BANG. Computer and printer were dead. The outlet the computer and monitor were in had a bad ground and the one the printer was in had a good ground.
Bad boys rape our young girls but Violet gives willingly.
Or
Simplicity?
There. I named two.
Mind you, I've never bought a lawn mower from the latter, but they strike me as a company I would like to do business with. I've been using Ernie Ball strings for years, and have always been happy with them.
Are you telling us you don't trust any company? Nobody sells you a good product at a reasonable price without committing crimes against humanity?
Where do you buy your groceries? Who cuts your hair? There isn't a restaurant, or a pub or a video store you enjoy patronizing?
Not one?
I don't care why you're posting AC
But I think that Slashdot editors should conduct themselves in a more professional manner. How else can we expect you to discharge your duties effectively, and eliminate the audience's natural resistance?
Now let's get back to the current topic.
I'll vote, too. I've had the same problem with my Dell E1505.
Many consumer devices show similar problems. I have a metal rack where I place my VHS recorder, DVD recorder etc. and everytime I touched both the rack and one of the screws of the DVD recorder I got a little electric shock. Maybe the reason is that the rack is grounded but the DVD recorder is connected to mains with a cable that does not include ground (i.e. with a two wire cable not a three wire cable). Maybe the inductive devices in the voltage coverter obviously cause a voltage difference between the "chassis ground" of the DVD player and the true AC mains ground -- I never bothered to measure that, I simply connected the chassis screw to mains ground to avoid the problem.
Experience has shown th
I've had this happen to me plenty of times on many different laptops. It if has metal leads on the bottom, towards the back (I think they are for charging a docking station) you will notice a slight tingling if you place it on your lap while wearing no clothing. (Yeah yeah. Admit it. You code naked too.) This is especially true if you've just taken a shower. It's not unbearable but you certainly notice it.
I think there is a world market for maybe five personal web logs.
Can anyone explain how exactely is the notebook electrically connected to the outlet? Unless the AC adapter is defective, there is ZERO connection between the two. There is way for the 110 mains voltage to reach the notebook.
For the electrical-engineering impaired, the notebook itself is powered from DC supplies (either the battery or the output of the AC adapter). The AC adapter is a fully isolated AC/DC converter; the power gets transferred through a switched transformer and the regulation feedback is passed through an optocoupler - zero galvanic connections between its input and output.
Well, I'm finally bored of the warcraft3 demo map. Last night alone It lets you play 1 on 1 against another person. How long has that map been out? Thanks Blizzard! You've given me years of free linux (wine) gaming. Now I've finally paid for it... got the expansion and strat guide too.
Last year while visiting my parents in law in Paraguay, I touched their desktop PC chassis, and got a nice shock. I had a test light in my laptop bag, and sure enough, enough current going from the case to ground to light it up.
They told me this is quite common there.
This story is completely impossible. The Dell Laptops, or ANY laptop is not going to have 120vAC power going into the unit itself. The Power Inverter that you plug into the wall and then into the laptop converts the 120vAC down to anywhere from 15vDC to 30vDC. Electronic Devices cannot run on AC voltages and especially precision electronics such as Computers would be extremely damaged from the application of such AC voltages ANYWHERE in the system. This is definatly a hoax and someone just trying to get a new laptop from Dell for nothing.
That's how three of my family members died!
We have a brand new Dell Inspiron 6400 with 55VAC (Fifty-five volts alternating current. It is not a typo.) between the chassis and earth ground. We purchased it in Dec 06. We are trying to get the problem resolved with Dell. The voltage only exists when the AC Adapter is plugged in. The AC adapter has a two pronged plug (as compared to a grounded plug with three) We haven't tried to measure the amperage on it and probably won't unless Dell tells us to. Anyone have any specific tests they would like us to try? AC
Doctor: What seems to be the matter?
Patient: I have a friend who has a medical problem, and he is not sure who to ask.
Doctor: And what are the symptoms you friend is reporting?
Patient: Erm, my friend has a red rash and a burning sensation when he takes a piss.
Doctor: Have you seen the rash? Describe it for me.
Patient: Yeah, red weeping pimples which are white in the middle, erm, he showed me a photograph.
Doctor: Here is a prescription and a leaflet on safe sex. Oh, and stop seeing my daughter, or I will fuck you up.
Patient: She gave it to me. My friend. Yes, my friend.
${YEAR+1} is going to be the year of Linux on the desktop!
I knew there was a good reason that I bought an HP laptop.. Also, my Gateway Laptop... Both of which have run perfectly since day one minus the stuff that they ship with.. Thank God for websites like this http://www.howtohaven.com/system/createwindowssetu pdisk.shtml
I work for the US Army, which uses nothing but 17" Dell laptops. I own 3 Dell laptops myself. I have never, ever heard of this. I think the "exploding battery" conspiracy theory has pretty much played itself out, no?
End of Line.
to control it? I mean this could be a great feature for motivating people at remote sites via the cattle prod approach.
=================
Unix is very user friendly, it's just picky about who its friends are.
Did you read the comments that the individual put online, as referenced in the original story? The guy owns a computer shop. He has tested THREE of them and found the same problem in each laptop. I'd say that the source is at least more reliable than some disgruntled clown, and finding the same problem in all three machines he's tested qualifies as a trend.
Excuse me, but who has their wiring tested regularly. Does the clean crew come through and replace the soap in the washroom and do a routine inspection on the wiring.
This whole thread seems like a troll and/or a whine.
I had a laptop that would crash after some time of use. Blowing the dust out of the system with a high pressure hose fixed the problem.
The real "Libtards" are the Libertarians!
Update: We called Dell's Premier Account Division's support number and informed the tech of the issue. Tech advised us that if it wasn't causing operability issues for the machine then they wouldn't do anything. I'm not thinking that safety ever entered his mind. Not wanting to scream bloody murder about a non-issue I went and rounded up one of our electricians to investigate this more thoroughly. He checked it out and confirmed that there is 55VAC there but the amperage is so small that it is not measurable. Even the load of the multimeter measuring the current depleted it. Does this present any danger? At this time we don't believe so. AC
Now if you hook a typical $4.99 digital voltmeter from Harbor Freight, the input impedance of the voltmeter, combined with these capacitors, will indicate anything from zero to 377 volts.
And if you rub your cat, the voltage could go much higher!
As you bright folks out there may be guessing, it's not the voltage so much that is the problem, it's the current. And the current is miniscule, microamps.
So no conspiracy here, move along, etc....
As he owns a computer shop, perhaps he's a biased source. He's trying to slam a competitor..."hey look this dell that you can buy is unsafe, or you could buy a reliable machine from me."
It's like pepsi saying that coke doesn't taste good (it may be true, but the source isn't reliable).
Perhaps if he would like to send me the "defective" dells I could inspect them. If they are are unsafe, I'd be willing (at great personal risk) to keep them so no innocent bystanders get hurt.
My HP Pavilion dv8000 is constantly outputting a voltage across the entire front metal grill. This is where you rest your arm when using the keyboard. I am constantly feeling the voltage as a slight sting, I don't have a volt meter but my tonge test would say it's about 5-10 volts ac(yes my tonge can detect ac vs dc, or is it my masterful logic that tells me so, given I have isolated myself and still felt the tingle.) Ok, let the cease and go flock yourself letters be unleashed.
For inspiron 9300 lcd screen issues see http://dellverticalline.com/
That they come with windows pre-installed.
In a shocking new development, the creator and patent holder of dance known as the 'electric slide' has filed a cease and decist motion to the users of the defective laptops. He cited reasons of doing the dance improperly after being zapped by the laptop and the subsequent sliding motion that followed.
Pretty much all of the backlight voltage is well isolated from ground and inside the display.
I have an old Presario and it floats at about 35VAC but can't deliver any appreciable current (more than 1 or 2 ma) at that voltage. I noticed this because I had some awful ground loops when using the laptop for ham radio, connected to a radio via the sound card.
I call BS. First of all, he doesn't say what impedance he measured the "leak" at. Second, his house wiring could be defective (is his neutral grounded and binded properly?) Third, he could just be posting "Feh Dell s3cz" everywhere and talking out of his ass. A "stop talking out of your ass" notice from a lawyer is not thuggery. (TFA is slashdotted so I couldn't get the details.)
I'm still surprised more PCs don't come with 3-conductor power cords, simply because there's so much defective house wiring out there.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
This is also true of all aluminum PowerBooks, and probably the MacBook Pro. More detail: When the PowerBook is connected to AC power using the two-prong plug (they're shipped with both 2- and 3-prong plugs), there is about 50vac present on the aluminum case. This is normal, though most people don't know about it. The good news is that it's a high-impedance source for this voltage. In other words, it's capable of supplying only a very small amount of current. Not nearly enough to injure you under any circumstance, but enough to cause an uncomfortable tingle. Using the 3-prong AC plug into a properly grounded outlet, this voltage is not present on the case.
I don't think any of us reading this has ever found a use for Mr. Happy on Saturday nights far from a pc screen.
It's the cover-up that kills you!
I swear to God...I swear to God! That is NOT how you treat your human!
too bad a lot of companies appear to do this. Samsung had an old 19" CRT monitor at one point where the controls would slide in and out of the casing. After awhile, that feature among others went away, but the model name never changed. They were now selling a lesser model that had the same name as the one that reviewed so well. I think it's a common practice.
It hasn't caused blown ram, but I have experienced a shock at least once per day for several weeks now. I just assumed that somehow I had built up enough static electricity that it made the jump from me to the metal tray for my laptop keyboard. I haven't experienced the hardware failures listed in the article, but for some reason, my power supplies have been failing. I've had 2 go out in the last 5 months.
IANAL... But I play one on
I wonder if the cause of the difference in voltages is based on locale? 65 is slightly more than half of 120V, and 139 is slightly more than half of 230V. The difference between the measured voltage and half of the line voltage could be the result of distortions in the wave form.
www.wavefront-av.com
The problem is that even if the current is miniscule, humans can feel as little as 1 mA. The LED lighting incident commented on earlier shows that the current is at least 1 mA, if not more.
The issue is that a laptop shouldn't be leaking any current. None. A circuit designed as you suggested is a potential lawsuit - if a capacitor shorts, the user gets full line current - not a very good idea. A person can be electrocuted well before a circuit protection device trips.
The society for a thought-free internet welcomes you.
Now, if you don't have a ground prong on your plug, the ground (as seen from the power supply) is floating at around 40 volts (or 80 volts in a 220 V mains). However, the current that can flow is very, very low. Yes, it is annoying if you get zapped, but it is not dangerous to you. It might not be all that healthy for other electronics though.
When trying to measure these kind of things, please do not use you multi meter which has an insanely high internal resistance. This gets you reading that are way off. Load the voltage with a 10 kOhm resistor and measure again, you will measure a voltage of nearly zero.
!ERR: Signature not found.
If you live in an arid environment, you already know all about static electricity. When I pull a polypropylene-fleece blanket off a bed that has a wool blanket, at night, the sparks will literally light up the room for the duration of the pull. I work in an electronics place, a design center so we don't have full bunnysuits, and everyone is familiar with the necessity of touching something metal as or soon after you stand up from sitting in a chair. I regularly work with hardware interfaces to my computer, and am pretty used to leaning forwards in a chair, and the separation from the chair back charging up enough that when I touch the circuit board, the computer reboots.
At the bottom of this page is a graph of air dielectric strength vs. air pressure. If you can get a 2 cm spark, that's about 60,000 volts. That's plenty to pass through the plastic case of a computer to something inside, or through the insulation on test leads, as I can tell you from personal experience.
Nostalgia's not what it used to be.
We're mandated on Dells where I work. An incredibly stupid user (the kind who gives you a headache as soon as you see her number on the caller ID) sent me her laptop once, saying it was doing "funny things". I was rushed, but I tossed it on my desk, grabbed the power cord, plugged it in ... and immediately got a huge shock on my leg where the brick (which sits in the middle of the cord on Dells) was touching. Enough to make me curse loudly and jump, and leave a mark on my leg.
Turns out the idiot user had mistreated her power cord, to the point where the wiring going into the cord had worn away... the covering, the insulation, down to bare copper. In her infinite stupidity, she saw this, and covered it with a bit of black hockey tape, apparently knowing about the magic fix-it properties of hockey tape when it comes to consumer electronics. Of course, even the job she did of taping it up was crap, the tape was coming off, things were shorting out, and in my case, zapping away.
How this woman wasn't reprimanded for extreme stupidity, I'll never know. My employers relative lack of response or sympathy certainly told me a lot about my then-boss.
That's what I think of when I think Dell and shock.
If I knew the wedgies I gave you back in 6th grade would have resulted in this . . . I might have taken a moments pause.
Nice job!
I don't think that's what's leaking - you'd have arcs coming off it and/or an ozone smell.
"Time is an abstract concept devised by carbon-based lifeforms to monitor their ongoing decay." - Thundercleese
I just had my video card replaced under warranty by Dell after it started to have problems @ 8 months old. The biggest issues I have with Dell is the over 2 hour tech support phone call, to tell them that it was a video card issue, not a windows driver issue when the text displayed in BIOS is garbled. It was amazing the things the tech support guy wanted me to try to figure out if it was the display or the graphics card, like wanting me to go find a magnet so I can wave it over the keyboard... I had to keep fighting the "reload windows" path by telling them that the graphics hardware was bad when their BIOS logo on boot is corrupted, and that fixing anything in windows, Linux, BIOS or anything on a CD would not help. Half of the call was strange questions injected during the debuggin session about "how" I use my laptop trying to figure out if I abuse it. Its basically a gaming desktop for me so it looks brand new and has sat on the desk never handled for months. Truly amazing (and frustrating).
Dell repair techs at my place of employ are often heard grumbling about the laptops they repair shocking the shit out of them. Dell's part of the warehouse continually smells like burnt electronics.
;)
Not that HP is really any better.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
My Dell Inspiron 1100 (I think it's 1100) has begun to shock me when I pick it up with both hands. Of course, placing the old clunker of a laptop on my lap requires two hands, so this happens often. I have discontinued using it, but it's my only windows machine at home and our corporate VPN requires windows. :(
"I threw up my hands in disgust and wondered if it had been such a good idea to have eaten my hands in the first place."
Bingo. Most of those backlights are little fluorescent tubes and run off AC generated internally.
Sounds like yet another reason to lust for LED backlit displays.
I forget what piece of gear I used to have, but one of them had a screw in it with a little lightning bolt sticker next to it. Sure enough, if you touched the screw (who could resist? oh, smart people) you got 120VAC down your finger.
I expect that one wasn't UL-listed.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Part of the problem with current laptops is that they are really portable desktops. So, your desktop CPU consumes 80 watts and has a heat pump, heat sink, CPU fan, and box fan to cool it. So, these portable desktops produce all this heat and dumps it into your lap.
Really. What I want in a laptop is a laptop. It can be 'slow'. But consider this. 10 MIPS is fast. 100 MIPS can currently be cooled without a fan. I want to take a 10x hit on speed, and gain 10x in battery life and reduced heat.
For that matter, flash memory is 'big enough' now to use as disk. I could have a totally silent laptop. Hey, then it could have good sound quality, and it wouldn't be pointless.
At that point, exploding batteries, etc., will be a thing of the past.
What will it take? Well, for one thing, it will take good software. Eye candy consumes batteries. Drop it. Huge programs take a long time to load. I'm willing to bet that movies could be played with the right hardware/software combination. Not that I want to watch movies on my laptop. I'd go for the monochrome version that gets 20x battery life.
-- Stephen.
The article is a bit barren, but the comments have some gems. Like this.
I have a dell 6400 with the better display and YES i do get little shocks every other time i touch it. I thought its ok, but i guess its not...should i call dell and address this problem?
I mean, holy f'ing 5h1t! How can anyone possible have to ask someone else that question.. Errr, Duhhh... My laptop is shocking me Bob... Should I call support?
I'm just astounded.
BBH
Peak detector-->DC volt meter-->Built in Sqrt(2) divider to compensate for the assumed wave form (sinusoidal)-->Display.
Short answer, never trust AC volts unless you're very sure about the wave form.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Of course they can fail. Solder joints can come loose, the capacitors themselves could have a undetected defect that becomes more apparent over time. As for factory testing, in a perfect would we could be sure that every one of the millions of units sold had every component that should be tested checked out properly, but the facts of life say that sometimes this doesn't happen, either due to accident, equipment issues (faulty testing/manufacturing equipment), human error if applicable, and even due to *gasp* cost cutting (like let's test every 1 of 3 and call the rest good).
There is no absolute, and no "doesn't fail, ever."
I was sitting on the toilet with my Dell on my lap, taking a nice long poop, and I got shocked through my asshole!
>> *sigh*, Is there not a company we can trust anymore?
...And for the low low price of $19.95 I will tell you about it!
> Has there ever been?
Of course there is!
I'd like to submit Logitech to the list!
I purchased one of their MX1000 laser mice when it was a brand new item, and while it was excellent - my 4 year old dropped it on the floor one too many times. The center rocker button surrounding the scroll wheel started sticking occasionally, causing things to scroll, out of control, in web browsers, MS Word, etc.
Seeing it was under Logitech's warranty, I figured it couldn't hurt to give them a call - to see if they might be able to sell me a used/refurbished replacement mouse inexpensively or something, given the circumstances.
Instead, the sales rep. looked up its serial number to confirm it was under warranty, and simply said "A brand new replacement is on its way." I asked if they needed the old mouse back, and I was told "No. You may as well keep it to have a spare charging base or something." Within a week, a new mouse was at my doorstep, in the retail packaging!
I had almost the exact same thing happen, the click function on the scroll wheel of my mx1000 randomly stopped working, and Logitech sent me a brand new one. I still have the old one as a backup with no middle click functionality, between customer service like this and the general overall quality of their products I always tend to buy logitech products.
Sounds great. Unfortunately they also license their name to third-party companies who don't respond to forwarded complaints about merchandise that falls apart.
the school i work at had purchased a couple hundred gx270 computers for their labs and i spent the better part of a few months on the phone with dell trying to get them to admit that the capacitors on the motherboards were faulty (nichicon capacitors)
i ended up replacing around 120 of them and a few weeks after i finished i got a call from dell saying they would send some technicians to the school to replace all the motherboards..
the dell people that i spent hours on the phone with were not allowed to admit that there was actually a problem - because then they might actually have to have a recall (i assume that's why)
http://www.gripewiki.com/index.php/Bad_capacitors
sounds like a repeat of some of my frustrations...
I haven't measured the voltage that mine gives off, but it will fairly consistently give me an electric shock when I touch one of the metal screws. Sometimes, I've gotten quite a shock via the USB port when my finger ventured to close when picking it up. Haven't had any problems with fried memory or such. The laptop is over 1 years old.
A decent AC voltmeter has an input impedance in the neighbourhood of 10,000 ohms. They are often capable of measuring a voltage that would disappear under any kind of load. You can rub a balloon on your head and create a gigantic voltage, but you can't connect up to the balloon and draw any sustained current. Just because a high-impedance meter shows a potential doesn't necessarily mean there is a real danger.
I have a m70 and I get shocks when I touch some parts of the notebook
does not happend everytime, but most of the time when I touch with my left arm the front side of the notebook I gets shocks like 9v bateries
I thought Dell make tested computers. This post has shocked me. I hope Dell will test next departs
I noticed this problem on my E1705 while I was in Israel recently. For days I experienced occasional stabs of pain in my left forearm whenever I had it pressed against the front of the laptop. I kept looking for something sharp or something that could have been grabbing the hairs on my arm but eventually I noticed a couple of tiny spots of bare metal on the housing where the paint had worn off. Immediately I suspected live voltage and sure enough when I put a voltmeter to it I could measure 30-40 VDC (never thought to measure AC) at the bare spot. And I noticed it would slowly charge up after a discharge.
However, the problem went away once I came home to the U.S. and I assumed it was related to the 220V service in Israel. Although this doesn't make much sense since the DC power supply should be supplying the same voltage to the laptop in either case.
I am the inventor of the hilarious refrigerator alarm.
This isn't an issue with the computer itself- (if there is a problem) it is a problem with the power supply- there shouldn't be anything above about 20V DC coming from the power supply itself. If the supply if double insulated (read no ground pin) there will always be a voltage between "ground" and the chassis of the computer- There is nothing magic about ground- it is just the common 0V reference, with enough insulation- it just doesn't matter. Seems to me that when you give someone a tool (VOM) and not enough understanding of electronics, you can create lots of hype...
GX5 for LIFE.
I own a Dell laptop...so this story really its 'h-ohm'!
I think the Dell company failed to 'conduct' itself appropriately
The news site will only be slashdotted 'faraday'
Some of the previous posts have been very 'en-lightning'
I wonder if the whistleblower will get 'grounded'
I wish this comment wasn't so 'short'.
I am ViriiGuy, and this is not true about me being banned off sites. This is a bit of an exageration on someone's part along the way.
Monkey! Monkey! Don't ya know you gotta shock the monkey!
Anyhow, why couldn't Dell do something simple like isolate the chassis ground from the casing screws? A few bits of well placed plastic or putting rubber feet over them can't be that complicated, can it?
Ordered a chew-proof dog bed. Lifetime guarantee.
Well, it wasn't totally chew proof, and I emailed them to ask for a replacement, cover and it was here in three days.
Also Logitech. They replaced my marble mouse trackball twice when buttons failed.
Dog is my co-pilot.
I've got a Dell Inspiron 1300, and I've gotten shocked from the case screws on numerous occasions. Though to be fair, I'm using a cheap third-party power supply; it's certainly possible it lacks some important safety feature.
So from the huge discussion off the originating site we have: Dell is improperly grounding some laptops with a 2 prong cord which may cause buildup of electricity which is harmful to the laptop in the longterm. It may even "tingle" under use in some situations. In typical large corporation fashion it is very good to rubbish in how it handles the situation depending on which person you happen to talk to.
From the slashdot blurb we have: A Big Evil Corporation is Keeping The Little Man Down by threatening him with lawyers and black helicopters if he mentions anything to the public about how the laptops can turn humans into Kentucky Fried Chicken.
Come on Slashdot.
I'd like to add bose to the list, even though most of their products are crap.
I had a pair of quiet comfort 2 headphones, cable started to break, they replaced the cable in store no questions asked (it was removable). About a 6 months later, just before warranty ran out there was some cracking on the plastic (minor, cosmetic only), complained online first, they said to ship it off, so instead I took them to the bose store, they exchanged them instantly in store, and about 3 weeks later I got a shipment from bose of a brand new pair. 2 for the price of 1.
Although the products were not so good, the customer service was top notch, and somehow they ended up accidentally shipping me a second pair of $400 headphones. My warranty is now out though and the headphones no longer work, although I am in the middle of repairing them and just need to reconnect one cable and they should be good as new.
The author says he found voltage when measuring it with a multimeter: a high impedance tool, which barely loads the circuit. The results from different tests have been inconsistent. Grounding the adapter makes the voltage go away. All this suggests the available current is low, and there may be no genuine hazard from the power adapter.
The adapter is a switch-mode power supply, which doubles as a radio jammer unless care is taken to control the noise on the input and output wires. The first line of defense is bypass capacitors: some from input to ground, some from output to ground. The value of the capacitors is kept low enough that the power line leakage current is considered non-hazardous: 3500uA maximum if there is a reliable safety ground connection, or 500uA if there is not a reliable ground. Also, capacitors connected to the AC line are required to have special safety testing and approval for that application (a class "Y" safety capacitor). So, it is entirely possible to have detectable voltage and current on the laptop's side of the power adapter if there is no ground connection: from the AC line, through safety-rated capaciors, to an ungrounded RF "return" in the adapter, through the output RF bypass capacitors, and into the low voltage leads. Connecting a ground wire to the RF return provides a much lower impedance than the output bypass capacitors, which reduces the leakage current and capacitivly coupled current essentially to zero. But the adapter with no ground can still be safe, and comply with CSA/EN/UL standard 60950, provided the leakage current is low enough and appropriate safety-approved capacitors are installed (giving "double insulation" or "reinforced insulation" between the AC line and the DC output).
This is the same reason you may see a tiny spark or feel a tingle in your fingers when you hook up a TV set (most have no ground wire) to the TV cable (which must be grounded, per the electrical Code). If the author had measured excessive leakage current at the laptop, or showed that the adapter was not properly insulated, or that it lacked safety agency approval marks, or that it had defective safety insulation--then he would have a case, and should take it up with somebody who can do something about it: the CPSC and Dell.
In a former life, I was a site hardware support engineer for a petroleum company. They had laptops that were used on Oil Drilling Platforms. (Steel, everything in sight earthed really well.) ;-)
I was handed a complaint that someone was shocked on one of these PCs. And, on testing, there was a potential of 75-150 volts between some of the exposed screws and earth. BUT, and this is the important point, the current was in the milli- to micro- ampere range. So, it meant that the electricity was perceptible, but not dangerous since the current involved was below the accepted threshold for danger to humans.
On the other hand, a spark, any spark, on an oil rig is not a good thing. The final result was that the PCs continued to be used in the office, but were banned from the oil rigs.
The above comments with respect to the current may not be the same as the situation reported in the original article, but I'd be curious to know what the measured current actually is.
When I measured current on the machines I tested, I started with the meter in it's highest possible current setting and gradually worked downwards to more sensitive scales to make sure I didn't let the "smoke" out of the meter. But if you're not sure about the method, don't try this at home kids.
Aside from making oily skin more conductive, a little bit of soap in that bath water makes it a pretty darn good conductor.
You don't need a return path to ground.... And if you are holding the laptop in more than one place and at least one is even 10V higher, you could feel a shock.
Don't believe me?
Try this:
1) Make your hand sweaty, through whatever means necessary.
2) Take a fresh 9V battery and put it connector-side-down into your sweaty palm.
3) Feel the power!
My Lappy is due to arrive tomorrow some time according to dell. The first thing I will do is stick a multimeter between it and the ground. If there is current, phoning Dell tech support will be the second thing I do.
In my next incarnation, I hope to come back as a code monkey.
Hmm,
Death Row Dells - News at 11.
I had a problem when I first received my powerbook from apple, they didn't include the grounded power plug in the box (accidently got left out from what I know) I could feel electricity coursing through the entire body of the laptop. So I called apple up, they confirmed this was the problem, and overnighted me a ground plug for my power adapter at no charge. All has been good since.
When I was growing up, my father had quite a few of the old tube appliances around: radios, intercom systems, televisions, etc. Quite a few of the simpler ones used an "AC/DC" supply. I.E. run it from approx 120VAC(RMS), or 170VDC. One side of the power line was directly tied to the chassis, with no isolation in the transformer.
Depending on what way you plugged in the cord, any exposed metal parts or screws securing knobs could be close to ground (neutral potential) or hot (110-120VAC).
Depending on the house wiring, even neutral can float a few volts different from ground...it carries the current, and there is voltage drop in the wiring and connections.
Wow! Thought those days were over...guess not.
I'd like Logitech if it wasn't for all the shit that they include with their drivers. A keyboard driver to enable some of their multimedia keys runs at 20+ MB because for some stupid reason they decide that I'd like to install Musicmatch Jukebox, and it doesn't even ask during the installation. At least this was the case with models we had at my previous workplace about 2 years ago, I hope they've cleaned up that act a little because otherwise I like their products.
Add Sumsung to the list.
I had / have two of their 19" LCDs.
One of them started ghosting / burning in.
I rang them, they told me that my models were no longer being made - waited for the kiss off - but instead, the next day a samsung rep arrived with two boxes - and replaced both monitors w/ the newer models - no questions asked, no cost.
Amazing!
Until recently I had an IBM Thinkpad R51 and was very happy with it. But just to do some R&D on Xen and virtualization I wanted to have something with VT supported processor and went for DELL Latitude D620. The funny thing is that they have disabled the VT support in BIOS (in a way that it cannot be enabled). I upgraded the BIOS to the newest version and the problem still existed. When I contacted DELL for this, they suggested me to downgrade the bios but it was failing saying the hardware is incompatible with this version of bios. The ticket with DELL is still opened and I dont see any chance of getting it solved (its already 2 months over). The funny thing is that I had swapped my Thinkpad only for this feature and I didnt get it. Plus, it has a lot of problems. Heat generation is horrible. Keyboard is nowhere near to Thinkpad. I can go and on... I curse my bad decision now.
http://www.nasirudheen.blogspot/
It's true that floating a cheap DMM's leads in the air (or even a very good DMM's) will show all sorts of spurious voltages, and that the "AC" voltage is not true RMS unless the meter says true RMS on the package... but users feeling a definite tingle through their skin indicates to me a problem, as does the demonstration (assuming it's true!) of pulling a milliamp over 1k off the "floating" case.
(Yes, IAAEE, and yes, one of my current [no pun intended] projects involves developing a device to zap humans - we EEs are our own most handy test subjects. Somewhat off the topic, the Big Boyz of the human-zapping industry set their 'danger zone' at around 10mA, give or take a little depending on pulsewidth, etc. Once you pierce the skin, human body resistance drops to only a couple Kohms...)
Caveat Emptor is not a business model.
I own a Dell Inspiron 8200 and I think I will never ever by Dell again. Since I have it, a hard disk,a 512MB memory module, and a miniPCI wireless card have gotten fried. The AC adapter also got fried. Dell does not know how to build laptops. No comment about their buggy bios and their lack of support for non-windows plataforms. Let's see if they have the guts to ban this one...
If they are providing an un-grounded adapter then they should be sure that no external metal components can connect to the line neutral, because while that should ideally be at ground potential, the power spec provides for the possibility of it floating.
In Canada, any low voltage external power supplies like one ones these notebooks probably use - and every other wall-wart or variant thereof - has to be a Class II rated supply. In other words, isolated from the line rather than referenced to line, and both short-circuit (output) and impedance protected (input) to assure that the output current cannot cause a fire and that the input current cannot burn the transformer. Look for the term "Class II" and a CSA or cUL mark (nb. UL mark with a small C to the left). I would very much assume that American rules are the same.
I seem to remember that Class II provides provision for some means to eliminate accumulated charge from the device, though such a provision would be in the form of multiple multi-megaohm resistors between primary and secondary, and exists to reduce static accumulation rather than anything else. The current possible between the user and a ground would be well below the human threshold and within range of only the most sensitive equipment - certainly not a 20,000-ohms-per-volt meter like you're going go find on a typical field service bench, but the lab-grade stuff used in component-level repairs.
In this day and age, I cannot imagine that the supply wouldn't be Class 2 rated.
Ergo, Dell must have gotten a bad batch of power supplies, ones which apparently failed the "HI POT" (HI POTential between primary and secondary) test.
Also, I'd like to see the testing conditions. Phantom or induced voltages along lengths of network cables could induce voltages with respect to ground, and they'd ironically be eliminated if the supply wasn't Class II rated (TV sets are often a great example of this, as you get a buzz from the coax as you try to connect it to the back of the set). ESD from external monitors. Remember that the only way to properly ground one of these systems is to connect it to a grounded peripheral (monitor, USB printer, legacy serial or parallel device) plugged into THE SAME OUTLET.
Fire and Meat. Yummy.
Submit Microsoft to the list too (yes I know we like to diss them, but...). I once had a Microsoft Optical Mouse (The very frist model - Intellimouse Explorer Optical).
Had a problem with the cable, about one year after purchase, Call up support (based in Reading UK). Here was the conversation:
- (through to a representative within 1 minuite of calling)
- Good morning Microsoft Support, how may I help you?
- I have a problem with my mouse, it seems like a cable fault?
- No problem sir, can i take a name, and a contact phone number?
- (gave my name and number, and was given a call ref number)
- Sir I am passing you to a technical engineer, to confirm your problem.
- Quickly passed through to the appropratie tech, who very quickly agreed it was a cable fault.
- then passed through to a returns representative.
- She took my name and address, and posted me a new mouse (which arrived the next day)
- When asked what I should do with my old mouse, she said, I can either dispose of it myself, or send it back free using the provided addressed bag for recycling. Or, she hinted, if i am technically inclined, I can try and fix the cable, and I will have a spare mouse to use with a laptop, etc!
Very good service, no quibble, and the whole phone call lasted 10 minuites. At no point was I interrogated, and finished with a smile on my face.
Since then, I have always purchased Microsoft Hardware, even at the slight price premium, simply for the knowledge, that if anything goes wrong, it will be fixed!
Have a nice day!
WTF? As one comment already explained, the problem only occurs when ungrounded power adapters are used. Three-pronged plug grounded ones remove this problem. So clearly it's not the issue of the EMI filter you described. As another post explained, the issue is capacitive coupling between the primary and secondary windings in the switching transformer. I am sorry that your misinforming post got moderated highly.
"Politicians and diapers must be changed often, and for the same reason."
Well if you read the original laptop posting, you'll see *it* was totally misinformed-- the fella was measuring between a screw on the bottom of the laptop, not guaranteed to be connected to anything, with the other lead going to, get this, an empty computer case sitting on his workbench. Plus they kept blaming the LAPTOP for the problem, not the adapter. They were barking up the wrong tree with the wrong dog.
If you use the wrong measuring device, hooked up between two inappropriate points, you're unlikely to get correct results.
Also the lighting the LED story proves *nothing*. Many homes have high-frequency noise from light dimmers and computers, such noise can ride thru power adaptors and light LED's.
I had a similar experience with Logitech. The analog knobs on the wireless controller I had purchased from them for use with my Playstation 2 gradually stopped responding. I contacted their customer service about it and they were very accomodating, and sent me a newer model immediately.
I have also had good experience with Antec. I have a case of theirs and, though it still has a defect I have yet to report, they have been very prompt about sending me replacements for parts without any charge to me, whatsoever.
I'm not having this problem with mi**zzzt**
Three-pronged plug grounded ones remove this problem.
Even if three pronged plugs solve the problem, there is still a fault, as no device should be sending stray voltage onto the ground wire. The ground wire in electrical circuits is a last resort escape for wiring faults to protect the user. If the laptop is sending stray voltage out the ground conductor, it would prevent you from plugging it into any GFI protected outlet, as the GFI is going to see a fault, and disconnect it.
I have an Inspiron E1505 and has fired me up quite a few times.