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New Dell Laptops Give Users a Literal Shock 383

An anonymous reader writes "According to CNET.co.uk, certain new Dell laptops with a brushed-aluminum finish are giving users more than they bargained for. 'We know this because several CNET staff were hit with an electrical charge while using Dell's new XPS M1530 — and we're not the only ones. Dell's forums are littered with user complaints about the shocking experiences they've had with some systems. The problem only seems to occur in Dell laptops that have a brushed-aluminum finish. These include the XPS M1330 and XPS M1530. It's caused by the two-pronged connection between the mains lead and the power adapter, which isn't earthed properly because of its lack of a third pin. The laptop therefore exhibits an electrical potential (voltage) between its exposed metal parts (the brushed aluminum wrist pad) and earth ground. Since there is no earth, the human body basically acts as a wire that can conduct electric current, hence the tingling, jolting sensation.'"
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New Dell Laptops Give Users a Literal Shock

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  • by Anonymous Coward on Thursday January 17, 2008 @07:03PM (#22086910)
    This is the new ground breaking experience with laptops!
    • Re: (Score:3, Interesting)

      by einhverfr ( 238914 )
      Customer's shocked by Dell's high-performance Laptops!

      Actually, on one of my trips to Indonesia I had a similar problem with my (three-prong) Compaq Armada. If I touched any exposed metal on the case, I might (or might not, depending on the circumstances) receive an electric shock.

      In that case though the problem was not due to the laptop but rather faulty building wiring. My guess is that either the earth ground was not attached to the wall socket properly or somewhere else a lot of electricity was being
      • Re: (Score:2, Informative)

        by Anonymous Coward
        You aren't putting AC into your computer. You are first going to a rectifier which converts it to DC. In an AC system, the third prong is designed to ground the case. In most settings it could effectively be connected to the neutral ground (wide prong) as well but this isn't done because if the neutral prong broke and there was an electrical fault then there would be no protection to the case. Your DC adapter, however, has no choice in this matter. Since the rectified output of your DC adapter is so lo
        • In general you are correct. However, this never occurred anywhere else, and it seemed related to the specific plugs I plugged it into.

          I didnt check the plug (and that laptop has long-since fallen apart) but that would seem to support an earth-grounded case.
          • Re: (Score:3, Informative)

            by Anonymous Coward
            There are a couple of things you can do to figure this out. First, you can check if you system ever shocks you when it is not plugged in and running off the battery. If it doesn't, then your fault lies somewhere before the charging circuit in your system (which would be dead when you are running on the battery but live when you are plugged in). Second, you can check the conductivity between your case and the DC ground (outer cylinder in your plug). If it is open, then your case isn't grounded. I haven'
            • by Vihai ( 668734 ) on Thursday January 17, 2008 @08:50PM (#22088194) Homepage
              The lack of the earth pin is not a lack of safety. Actually, double-insulation appliances MUST NOT be grounded, thus they miss the earth pin. http://en.wikipedia.org/wiki/Double_insulation [wikipedia.org] If you have a class I power supply and you plug it in an outlet with faulty ground the EMI filters (yes, they are connected between both neutral and line to ground) will induce a mains/2 voltage on the chassis with an impedance high enough to be felt. Thus, if you feel electricity on the chassis of an appliance check that the earthing of all your Class I appliances is good.
    • Re: (Score:3, Funny)

      by plover ( 150551 ) *
      Dude! You're getting a shock!
  • Ooh, (Score:5, Funny)

    by Voltageaav ( 798022 ) on Thursday January 17, 2008 @07:03PM (#22086916) Homepage
    Where can I get one? I need a presant for my mother in law.
  • by jellomizer ( 103300 ) * on Thursday January 17, 2008 @07:04PM (#22086918)
    To be fair to Dell this happened on my PowerBook and not so much on my MacBook Pro... But sometime I do get a tingle, in the right condition.
    • by tsotha ( 720379 ) on Thursday January 17, 2008 @07:13PM (#22087068)
      That tingle is from the websites you're visiting.
    • by gigne ( 990887 )
      I also get this on my Compaq presario laptop from the front aluminium plates. I currently have duct tape over them to stop the shocks. My previous laptop, a Toshiba satellite has screws on the sides that shocked too.
    • by Animaether ( 411575 ) on Thursday January 17, 2008 @07:14PM (#22087074) Journal
      ...after all, no part of the casing *should* be making contact with the electrical parts at all. The whole thing with making the casing grounded is for the unfortunate event that it does; typically as the result of some manner of physical malfunction within (e.g. a wire coming loose).

      That said - my acer laptop has a brushed aluminum finish and has the same problem *if* I don't plug it into a grounded wall outlet (as it currently isn't). It doesn't feel so much like a jolt or a tingle, however, as that the surface feels strange.. almost like it's vibrating at a high frequency; but only when touched very, very lightly.. a firm touch increases contact area and away goes that odd feel.
      Surprisingly, the metallic finish (probably aluminum as well) on my USB keyboard has the same thing going on.
      Again, though, if plugged into a proper outlet, the problem goes away.

      It seems fairly common for the housings of low-power (and yes, a laptop is pretty much low power; although a 'jolt' sounds light it might be otherwise.. high performance gaming laptop sucking 150W+ perhaps?) to not be properly insulated, though.. I can probably walk around the house and find a dozen more appliances that exhibit this.
      • by pz ( 113803 ) on Friday January 18, 2008 @12:10AM (#22089656) Journal
        It doesn't feel so much like a jolt or a tingle, however, as that the surface feels strange.. almost like it's vibrating at a high frequency; but only when touched very, very lightly

        Run do not walk away from any situation where this is true. The casing you are touching is not at ground, and you are feeling the 50 or 60 Hz current (that's the high frequency vibration you're feeling) flowing through you. Don't believe me? Next time you experience this, put an AC voltmeter between the pseudo-vibrating chassis and ground. You'll see between 6 and 20 VAC (at least that's the range I've observed). This is the mains current leaking onto the chassis.

        There are many reasons for this, but they almost all boil down to poor design of the equipment or inexpert wiring of the mains outlet. Often the fix is to unplug the two-pronged plug and re-plug it in the other way around. This isn't always possible with polarized plugs (which were *supposed* to make this not nearly as much of an issue, but then, that relies upon all outlets being wired correctly and my experience is that only about 80% of them are).

        Do not ignore this when you find it. It is a potential danger. If you're in a country where they use 220/240 VAC, it is of particular concern.
        • MOD PARENT UP (Score:5, Informative)

          by DMUTPeregrine ( 612791 ) on Friday January 18, 2008 @01:37AM (#22090064) Journal
          He's correct. It's a safety issue.
          Also, prolonged contact with (nearly) ANY electrical current that you can feel can become dangerous. While a low voltage won't be able to pass much current through the skin (skin resistance) initially, this situation will change. As voltage flows skin resistance slowly decreases, and can lead to fatal currents if allowed to persist for long enough.

          Effects of current through the human body (rough):
          0.2 amp - no fibrillation. Severe burning and breathing halted.

          0.1 - 0.2 amp is the most dangerous zone, because fibrillation is a faster death and harder to stop than a mere stoppage of the heart as occurs above 0.2 amp.
          Skin resistance is about 1kohm for wet skin and 500kohm for dry skin. Internal resistance is 100-500 ohms, so current penetrating the skin is what causes problems. Higher voltages let more current through, so above 240V current easily penetrates the skin. If you touch a wire of 0.02 amps or so your muscles will contract, forcing you to hold onto the wire. Since skin resistance drops over time you will soon find it difficult to breathe and eventually you WILL die.

          If you find someone stuck to a wire in this manner, the person WILL die if they are not removed. Do not attempt to touch them uninsulated, since you will likely become stuck yourself. Turn power off, or push them off with a stick or other non-conductive object.
          • Re:MOD PARENT UP (Score:5, Informative)

            by p0tat03 ( 985078 ) on Friday January 18, 2008 @04:11AM (#22090630)

            Furthermore, if you ABSOLUTELY must touch something with your bare hand without insulation that you suspect may be electrified, DO IT with the BACK of your hand. This way should your muscles contract, at least you won't have made a death grip on the wire.

            That being said... Just don't touch stuff you think is electrified.

        • by Skapare ( 16644 ) on Friday January 18, 2008 @02:40AM (#22090330) Homepage

          If you are only getting less than 30 volts between the metal case and a true ground, then it is capacitively coupled to the mains hot wire, or capacitively coupled to the transformer primary. If it were fully connected you would get the full line voltage, 100 to 240 volts depending on where you are. The later is extremely dangerous and could result is big electrical arcs and human corpses. The former is very annoying but not an emergency.

          No computer should ever be designed to be operated without the earthing wire used to connect to the case to drain off the capacitively coupled voltage. This big reason, though, is not to eliminate that vibration feeling, but rather, to provide a safety path for electricity to go back to ground should a wire break or whatever and accidentally fully charge the case. That would be a quick short circuit and should throw off the circuit breaker.

          If the source of the voltage on the case happens to be capacitive coupling in the transformer primary winding, and if the power is plugged into a 240 volt outlet in the USA (which normally uses 120 volts for most things), then you are likely to not get any vibration feeling at all. This is because 240 volts in the USA comes from a pair of 120 volt wires of opposite phasing. The balance between them is effectively 0 volts relative to ground. Power connections this way (both wires are equal but opposite voltage relative to ground) can also eliminate hum from audio equipment that might have that issue.

          In any case, if you get a computer with no earthing pin on its AC mains power connection, you should insist that it be replaced (at least the AC adapter part) with one that has the proper connection to earth/ground.

    • It's nothing at all to do with the power cord, the user is looking at pictures of Natalie Portman :-)
    • by wbren ( 682133 )
      It happens on the Dell Latitude I use for work... the thing is, that laptop is made of plastic, so.... Yeah, maybe I should get that looked at o.O
  • by MikeyVB ( 787338 ) on Thursday January 17, 2008 @07:04PM (#22086920)
    ...what happens when you lick it?

    Better or worse than a 9V battery?
  • by BUL2294 ( 1081735 ) on Thursday January 17, 2008 @07:04PM (#22086926)
    "Dude, you've got a Dell!"
    • There's a new advertising campaign in the works here. Register "dellshocker.com". Run some commercials along the lines of the Burger King "freakout" idiocy. ????. Profit.

      (I'm not sure how the "freakout" campaign is supposed to work selling burgers either - but someone at BK bought in to the idea... why not Dell?)
  • by zardie ( 111478 ) on Thursday January 17, 2008 @07:06PM (#22086946) Homepage
    The Apple PowerBook G4 aluminium systems have also suffered from this - but only when using the 2-pronged power plug. If I use the actual cable between the power adaptor and the wall (with three pins) then this is no longer an issue.

    I believe the MacBook Pros also suffer from this however I haven't tested this.
    • by jfinke ( 68409 )
      Interesting... I have a third party AC adapter that is only two plugs. I noticed that this would start to happen. I never lined up the two. It is really bad when I have my dell on my lap and then I touch the powerbook.
    • by v1 ( 525388 ) on Thursday January 17, 2008 @07:34PM (#22087346) Homepage Journal
      I've used a macbook pro and powerbook for some time, always with the two prong pack, and I have yet to get any tingle from the case. One thing that is being overlooked here is that the lack of a ground pin is not the cause. To get a buzz off the case there has to be an original path from the outlet to the computer, to allow your body to be the return path.

      Many electronic power packs use "transformers", which use two isolated, closed loops to transform power, magnetically coupled. (to make a trade off of voltage for current, since laptops need 12v and the wall gives 120v) There is no path between the two, and you could start chewing on the power wires if you wanted to, (one at a time I would advise) without getting the slightest buzz.

      The only way you could get a buzz off the case is if the case is grounded (via the 3rd pin) and that there is a ground fault in your area of the building (in which case you would get a buzz by sticking a paperclip into the ground pin on the outlet) OR if the pack was a more direct regulated power and was designed poorly. (like connecting the center tap off the 120v side with the center tap on the laptop side)

      Devices experiencing a minor short that have a ground pin can cause equipment all over the building to buzz you. Attach a GFCI (ground fault circuit interrupter) power strip and see if it trips where you are seeing the problem. It just might. I've seen cases where when I plugged in a certain power tool and revved it up, it would trip every GFCI outlet in the house. Same effect, caused by the power tool's bad (dangerous really) design.

  • Please (Score:5, Funny)

    by Daimanta ( 1140543 ) on Thursday January 17, 2008 @07:08PM (#22086974) Journal
    Don't shock me bro!
  • The exploding / burning batteries, or the electric shock?

    I think I'll stick to my ThinkPad, thank you much...
  • xps m1330 owner here (Score:5, Informative)

    by yourexhalekiss ( 833943 ) <herp@d[ ]step.com ['erp' in gap]> on Thursday January 17, 2008 @07:10PM (#22086994) Homepage
    I've had an aluminum-brushed XPS m1330 for about four months now, and I've never experienced a "shock" like the article is suggesting. I don't doubt that the CNET editors have experienced this, but I'm certain I would have remembered it if it had happened to me.

    I checked, and my 1330 has a grounded three-prong plug going into the wall, and a three-prong plug going in to the power brick. Maybe the UK 1330s/1530s are different than the American ones?
    • by Alioth ( 221270 ) <no@spam> on Thursday January 17, 2008 @07:16PM (#22087106) Journal
      They probably are. Having lived in both countries, where most UK devices are almost always properly grounded (the earth pin is not optional in UK power plugs because you physically can't plug something in that doesn't have one - the earth pin opens the shutters in the wall socket), a great number of US appliances lack a ground pin.

      Perhaps because 110 volts is seen to be less dangerous than 240v, it gets omitted.
      • by RikF ( 864471 ) on Thursday January 17, 2008 @07:20PM (#22087174)
        Heh - check again! The UK plugs may need to have 3 pins but quite often than third pin is plastic and unconnected
        • by PeterBrett ( 780946 ) on Thursday January 17, 2008 @07:46PM (#22087526) Homepage

          Heh - check again! The UK plugs may need to have 3 pins but quite often than third pin is plastic and unconnected

          Only unearthed devices using power-supply protection described as "double-insulating" may substitute a plastic 3rd pin. Typically, these have (very) heavy insulation on the mains side of the power supply, and then use an internal transformer to "float" the device's electrical workings so that any inadvertent contact with a person just changes the circuit's point of reference without causing a shock. They would not exhibit the symptoms described in this article.

          Any devices you might own which have a plastic third pin and don't bear the label "Class 2" or the double insulation symbol are unsafe. Get them looked at by someone competent. As a point of reference, a brief poll of the various devices around me here found one Class 2 device -- the LVDC transformer for my desktop speakers. And a hauling out the schematics, yes, the transformer has a floating secondary.

          BTW, the reason you see a lot more Class 1 appliances in the UK is because that is the preferred design for any device that uses more than a trivial amount of power. In a Class 1 device an electrical failure cannot bring the chassis to mains potentials without blowing a fuse, whereas in some pathological cases Class 2 devices fail to fail safe (if that makes sense).

          The problem discussed in the article has nothing to do with what sort of plugs are in use. Class 1 devices, properly earthed, are safe. Class 2 devices, properly insulated, are safe. The problem in TFA is that the safety features of the electrical system weren't used properly, thus causing a hazard. Much the same as if you have a Class 1 device without a ground connection -- a charge (which would normally be rapidly dissipated to ground) can very slowly build up on the chassis, leading eventually to a shocking result.

      • Re: (Score:3, Interesting)

        by pcgabe ( 712924 )
        It's even worse in Japan. You can't physically plug something in that DOES have an earth pin; the sockets aren't made for them. There's no grounding at all*. I guess 100 volts must be safer than 110v.

        (* not entirely true, some outlets have a grounding tab on them, to which you can attach a grounding wire from certain appliances. But not every appliance, nor every outlet. Or even most. Or half. My last apartment had two outlets with grounding tabs on them, total.)
    • by kv9 ( 697238 )

      I checked, and my 1330 has a grounded three-prong plug going into the wall, and a three-prong plug going in to the power brick. Maybe the UK 1330s/1530s are different than the American ones?
      seen it happen to a workmate the other day. quite rare though. ungrounded.
  • by Kingrames ( 858416 ) on Thursday January 17, 2008 @07:11PM (#22087012)
    The machines have struck the first blow!
  • by seanadams.com ( 463190 ) * on Thursday January 17, 2008 @07:11PM (#22087014) Homepage

    the two-pronged connection between the mains lead and the power adapter, which isn't earthed properly because of its lack of a third pin.

    That explanation is over simplified. Tons of metal-encased devices have only two-prong leads and are perfectly safe. My Apple laptop for one, and a lot of stereo equipment as well.

    UL allows this if the device is sufficiently isolated. What is sufficient depends on the type of device, the type of power supply, whether the supply is internal or external, and so on. Usually it means that the DC output of the power supply has a very high impedance with respect its input, and also that the metal chassis of the device is floating (with specific distances and or dielectics between it and any possible potential) and/or has a non-conductive finish. I'm not sure but I think even just clear anodizing would meet that requirement. I just tested my MacBook and all the aluminum surfaces are not conductive, suggesting such a finish.

    In order for the Dells to be zapping people they must have doubly screwed the pooch: wall wart is putting out a high potential, AND the case is not properly insulated.
    • by geekoid ( 135745 )
      Actually, from what I have read, the device was designed for three prong only. For somereason the UK got two pronged plugs.

  • by rainer_d ( 115765 ) on Thursday January 17, 2008 @07:13PM (#22087050) Homepage
    It keeps you awake in those meetings that seem to take *forever*.
    Just keep in touch with your Dell laptop.

  • by englishb ( 1165253 ) <[englisb] [at] [hsu.edu]> on Thursday January 17, 2008 @07:13PM (#22087060) Homepage
    I guess you could say that the folks who bought these laptops got a shockingly good deal.
  • by d474 ( 695126 ) on Thursday January 17, 2008 @07:13PM (#22087066)
    "We deny all charges."
  • by Tmack ( 593755 ) on Thursday January 17, 2008 @07:17PM (#22087118) Homepage Journal
    Since the "neutral" line is actually ground as well (it ties to the grounding bar at your breaker panel), the "Ground" wire itself is really just an extra protection in case one of the wires goes bad or electricity flows to where it shouldnt. This case of electrical shocks (pun not intended)is due to improper grounding in the power supply brick of the power going from it to the laptop itself, and of the laptop's case against the innards of the machine. If it were just the lack of a 3rd pin on the power brick, then why does my macbook (and why did my powerbook before that) never shock me (both have a 2prong only plug, or 3prong cord, never been shocked with either in use)? It is simply a poor electrical design. And the "tingly" feeling is most likely AC current (dc would just lock your muscles, AC makes you twitch), rather than simple static buildup, meaning the circuits are actually leaking AC current from somewhere to the case, which should never happen since the power brick should only be sending DC to the laptop.


    • WRONG! (Score:5, Informative)

      by seanadams.com ( 463190 ) * on Thursday January 17, 2008 @07:31PM (#22087306) Homepage
      Neutral is neutral and ground is ground. The fact that they are connected to each other at the service entrance does NOT mean that neutral can be used as a ground reference.

      From the device's perspective, neutral must be treated as AC line input, never ever ever as a ground.

      Any number of wiring faults could cause the neutral to become hot, and even under normal circumstances it is common to see some potential on neutral relative to ground, because loads on the branch circuit are pulling it towards one phase or the other.
    • Since the "neutral" line is actually ground as well (it ties to the grounding bar at your breaker panel)

      Actually, it totally depends on your local electrical system. In the UK the grounds are usually tied to neutral at a substation. It's also possible for 'ground' to be literally that - a conductive-tipped pole driven deep into the ground somewhere near the property. I'm sure there is variation within the US too.
      • > Actually, it totally depends on your local electrical system.

        In the US ground is tied to earth at the service entrance, as is the neutral. Ground and neutral are connected together nowhere else. The service from the utility does not include a ground: just neutral and two 120V lines (240V between them). The utility's neutral is grounded at the transformer.

        > I'm sure there is variation within the US too.

        I don't believe that there are any jurisdictions in the US that have not adopted the National El
    • The "neutral" is connected to the center tap on the transformer in split phase systems. The ground (green) wire has to be connected to the neutral bus or it would be point less (no return path).

      * In sub panels the neutral and ground should never be connected (ground loop)!
      * The neutral wire has the same amount of energy running through it as the black wire!
      * A GFCI outlet will save you from your shitty Dell. Install them!

      http://en.wikipedia.org/wiki/Split_phase [wikipedia.org]
    • Yes, the neutral is also tied to ground at the breaker panel, like the ground.

      But the thing is the neutral is designed to ALWAYS carry current, it's part of the circuit. The ground is there for safety and usually carries no current.

      Why is this important? Well, if ground is at 0V, but the wire between the outlet and ground is 1 ohm and carrying 15 Amps, then the neutral at the outlet will be at 15A * 1 ohm, or 15V (AC in this case). So now there is a voltage difference between neutral and "true" ground (whic
    • (dc would just lock your muscles, AC makes you twitch)
      In my experience, dc tends to also make you twitch (once, often breaking the circuit). I think this is because the current doesn't normally flow equally through all muscles (if this seems odd, as yourself why the currents would be equal). Since that means you get differential contraction forces, you get net movement.
    • I bet the tingly feeling people are getting is leakage of the high voltage AC from the inverter for the display backlight.
      A cold cathode light uses about 700 volts AC 50hz at 4ma or so. This would definitely feel tingly.
      You would not feel 12VDC at all.
  • 3 things (Score:4, Informative)

    by sayfawa ( 1099071 ) on Thursday January 17, 2008 @07:20PM (#22087172)
    1) It seems as if it's UK only. American ones come with the ground prong on the plug

    2) People who complain are getting new plugs with the ground prong and the problem goes away (not that they should have to complain).

    3) On the forums linked to in TFA there's a response from "a Dell guy":
    To the tingle, you are absolutely correct, it's a grounding thing. Dell product design went from a 3 prong grounded plug at the outlet to a 2 prong "floating ground". The tingle you get is your body feeling the circuit. If you wish to eliminate that sensation, use the system on a solid surface such as a table or put something between the bottom of the system and you that's thicker than typical blue jean or khaki material. If you're more concerned than that the 2 prong adapter can be replaced with a 3 which eliminates it. As full assurance, the voltage you feel is decidely not harmful and there's no risk of electric shock.

    Whaa? Even if it's true that it's not dangerous, who the hell wants current running through them all the time? That tingling feeling isn't very pleasant. I know, I've had it from other appliances (and from sticking my tongue on batteries).
    • Re:3 things (Score:5, Informative)

      by moosesocks ( 264553 ) on Thursday January 17, 2008 @08:22PM (#22087908) Homepage

      1) It seems as if it's UK only. American ones come with the ground prong on the plug

      Not possible. A UK socket [wikipedia.org] physically *requires* that a ground pin be present. The ground pin is a bit longer than the live/neutral pins, and is used to open a "shutter" blocking the live/neutral holes when the plug is inserted. When the longer ground pin is inserted, the shutter opens, allowing the plug to be fully inserted.

      As an additional safety precaution, every plug is also fitted with a 13A fuse, and all domestic circuits fitted with the connector described above are *explicitly* rated to operate at up to 13 amps. (Additionally every single wall socket also has an individual on/off switch)

      The UK/Ireland wiring standard is arguably the safest in the world, and makes the North American NEMA standard seem primitive and dangerous by comparison, as outlets are not shuttered, circuits do not have an explicit amperage rating, and no ground pin is required.

      (There's also an older 15A British standard that's still used in some former British colonies and dimmable theatre installations that lacks the fuse and shutter mechanism, and is electrically compatible with the "new" standard with the use of an adapter, despite lacking the newer standard's safety features)

      Mind you, the ground pin doesn't actually have to be connected to anything, nor would one expect it to on a laptop, considering that no grounding is possible when the laptop's running off of battery power, nor should AC power ever even enter the laptop's chassis.

      Sounds like either Dell screwed up the design, or CNet installed carpeting in their UK office.
  • by Paranatural ( 661514 ) on Thursday January 17, 2008 @07:20PM (#22087176)
    The engineers giving in to the Helpdesk people.

    Think of the possibilities!

    Tech: Ok, put your mouse over the 'My computer' Icon and right click...
    Guy: Why does this have to be so complicated? Why doesn't everything just work right the first time? You Idiots should be shot!
    Tech: Well Sir, if you would just...
    Guy: I'm tired of you people and your attitudes, why I should...*ZAP* AHHH! WHAT THE HELL WAS THAT?
    Tech: Now what did you learn?
    Tech: A bit slow today are we?
  • Seriously, why can't electronics manufacturers take the simple step of grounding everything? Why would you use a two pronged plug anymore at all?
    • Overall Happier Customers. a 2 prong plug will fit in anywhere 3 prong will only fit in 3 prong. Being some houses are a bit older don't have 3 prong plugs. Selling systems with 2 prongs is good reasoning.
      • Actually, if you live in one of those houses then you probably know about the three prong to two prong plus ground clamp converter. They are meant to be used with the clamp actually grounded but you COULD get by without using it like that. Of course if you live in a house like this your lucky to get a computer to work at all as your power is probably 20 shades of dirty.
  • by Tavor ( 845700 ) on Thursday January 17, 2008 @07:25PM (#22087228)
    Cut open an unplugged three prog extension cord, exposing the three wires inside.
    Cut open Dell power cord, exposing the two wires inside.
    Position pieces of heat-shrink tube over the stripped inner wires to be joined.
    Connect positive extension cord wire to positive laptop wire and solder.
    Connect neg. wire to neg. wire and solder.
    Connect the third ground wire to the exterior casing of the laptop with tape as to be removable.
    Cover over the sealed three wires with heat shrink or electrical tape for asthetics.

    Disclaimer: I'm assuming everyone here knows what they are doing. Mains power can be very hazardous and very deadly. Do NOT attempt this if you are unsure of what you are doing -- call someone more experienced if in doubt. But for those of you who know what you are doing, this should be an easy fix to avoid the shock of you being used for a ground wire.
    • by Dachannien ( 617929 ) on Friday January 18, 2008 @12:38AM (#22089822)
      You can also follow this procedure for getting the mains back online:

      Enter glass-walled reactor room
      Remove shiny tube cover
      Hold hands over open end of tube in mysterious fashion while leaning over tube, ensuring maximum irradiation
      Replace cover, waddle over to locked door, collapse
      Die in dramatic fashion while taking a subtle parting shot at your best friend for his lack of manual dexterity

      Optionally, you might consider transferring your katra to someone else beforehand, especially if you've been thinking about directing and would like a shot at it in your next movie.

  • I'm guessing they probably mean grounded. I've never heard of that term, maybe I'm out of the new slang loop?

    • Re:Earthed? (Score:5, Informative)

      by anonymous_echidna ( 1019960 ) on Thursday January 17, 2008 @07:43PM (#22087474)
      In Australia we use the terms "earth", "active" and "neutral", coloured respectively green, red and black.
      There is no need to be *shocked* that other conventions exist. "Earthed" is not wrong, it's not slang, it's just not standard in the US.
    • Re: (Score:3, Informative)

      by geekoid ( 135745 )
      earthed was more commonly used in the US 30+ years ago. Mostly people say grounded.

      Since my initial electronic instruction in the 70s was from my grandfather, I will often use the term 'earthed'.
    • Re: (Score:2, Informative)

      by El_Isma ( 979791 )
      In Spanish we say that a device has "tierra" (direct translation: "earth").
  • I've never heard it put that way before. In US English, we use the word "grounded". Is that a bad transaction from a non native speaker, or is there some place that they use the word earth instead of ground?
    • Earth Ground is common usage in power supply and EMI design. It's a non-current bearing wire meant to ensure all devices are at the same potential, and provides a return path for stray voltage.
    • by JVert ( 578547 )
      In US English we use the word translation, native speaker.
    • Re:earthed? (Score:4, Informative)

      by aXis100 ( 690904 ) on Thursday January 17, 2008 @08:17PM (#22087874)
      I'm in Australia and we use the term "Earth" interchangably with "Ground", with a preference for "Earth".

      On a similar note, alot of people are questioning the use of "Mains". In Australa it referes to the main utility supply - eg the 240V wall socket.
  • That reminds me, I got something like this on the ThinkPads that I owned (R50, R51). I got an occasional zap (felt like the usual static zap when you rub shoes along a nylon carpet then touch a door). My way of dealing with this was, before I used the computer),to bunch my hand up into a fist (tightens the muscles, which makes the shock hurt less), then touch the front part of the keyboard with the soft part of my hand.

    I've had no static problems with my current laptop (which does actually have a grounded p
  • I have a Dell XPS M1330, and the aluminum keyboard rest area causes my hands to tingle...weirdly though, it only happens when I have a device plugged into the left USB port. A shame that bizarre build/design flaws mar what is otherwise one of the best laptops Dell has ever made.
  • My XPS M1210, which I think is the predecessor to the M1330, does this frequently as well. Though it's mostly plastic, the touchpad and the trim surrounding it, and various metal bits have given me shocks. It's not a fun surprise.
  • If a device is not properly grounded or has problems where it provides a small electrical shock, can this be a potential health hazard for people who may have certain types of medical implants - e.g. implanted pacemakers, defibrillators, or other devices?

    I suppose any potential threat could be worse if the current were conducted for example - from one hand across the body to the other, so that it would travel across the chest or implant while seeking ground...
  • When you connect your transformer to the mains, what do you expect? 76kV is way too much power for that small transformer. Try plugging it into line voltage, which here happens to be a measly 120V.

    • by dbIII ( 701233 )
      The problem here is that somebody was writing in English and you were reading in American slang. It's a big world out there.
  • As any electrician will tell you, with two phase 110v in the U.S. (most homes and establishments) You have only hot and ground. If you rip open your electrical box you will notice three wires coming in. +120, -120, and ground. All the white wires and grounds get connected to the same buss. The hot (black wire) gets a fuse or breaker to either +120 or -120. (220v appliances get two breakers linked together.)

    The people getting a shock probably have their outlet wired incorrectly.

    I doubt very much it is Dell's
    • by KC7GR ( 473279 )
      Ahhh... no, not quite. You're referring to the two hot legs of a typical household AC power feed as if they were DC, which is a dangerous misconception at best.

      There is no "+120" and "-120" in house mains. What you have are two 'hot' phases with the AC on them separated in phase angle (theta) by about 90 degrees (you'd need to look at them with a power analyzer or ground-isolated oscilloscope to see this), and a neutral.

      Typically, if I recall correctly, the two hot phases are connected to the outside ends o
      • First, about 20 years ago I was an electrician, and worked as an EE designing motor and power circuits as my first job, so I kind of know what I'm talking about.

        Ahhh... no, not quite. You're referring to the two hot legs of a typical household AC power feed as if they were DC, which is a dangerous misconception at best.

        For canonical reference only, it works for discussion, especially when you have a broad audience.

        So: My take on this issue is that it is indeed bad design on Dell's part, most likely the resu
    • by geekoid ( 135745 )

      You have a ground(this path leads to a copper pole hammered into the ground), neutral(white or gray, maybe with stripe) goes to the center tap on the transformer, and Red/orange/black is the phase wire.

      This prevents drift.

      If this wasn't wired correctly, who would get voltage the varied from 80-120 volts. This would cause havoc with any appliance plugged in.

      This is Dells fault, they admit it,and will send you a new cable.

    • by Ignis Flatus ( 689403 ) on Thursday January 17, 2008 @08:11PM (#22087802)
      no, but IAA electrical engineer. it shouldn't matter if ground is missing, 110V vs 220V, or if hot and neutral are swapped. if you are getting shocked from your laptop, it's either bad design, a manufacturing defect, or some other part failure. these people are probably feeling a static charge that has built up on the metal case parts. if there's mains voltage on the case, then you should be able to measure it with a meter.

      if there were an actual short to the plate, i'd look somewhere non-obvious. like maybe an inverter used to step up voltage for the display. (and no, i do not have any specific knowledge of the voltages used on modern displays)
  • about a year and a half ago, the company i was working for sent me to a class to learn a new software package. the class was taught using dell laptops.

    everytime you'd start working on a lesson you'd get zapped.
  • Thats because the power supplies have to meet UL and VDE specifications which say that if thousands of volts are present on the AC line, nothing gets through to the computer.

    Perhaps what you are experiencing is some AC getting through the RF filter on the power supply. Sometimes there is a very small HV cap between AC side and DC side (i.e. computer)

    I guess in summary I would have to say that the power supplies involved are poorly designed and/or faulty.
  • by Lionel_Menchaca ( 1222156 ) on Thursday January 17, 2008 @09:33PM (#22088562) Homepage
    Last year, I posted detailed information on the tingling sensation sometimes associated with leakage current http://direct2dell.com/one2one/archive/2007/04/24/8522.aspx [direct2dell.com]. Since the story, I re-visited the issue with members of our Engineering team. Here's what they had to say: Even though the leakage current is extremely low and well within safety limits, it is perceptible by some people. This perception may be experienced as a mild "tingling" effect. However, if that "tingling" effect is coupled with an electrostatic discharge, such as is experienced when walking on carpet in dry conditions, the total effect can be surprising but not harmful. The primary effect being felt is from the electrostatic discharge (static electricity). Typically the tingling sensation can be eliminated with a three-prong adapter, however a three prong grounded AC adapter will not eliminate the electrostatic discharge. The tingle is not harmful to the users or the system components. Again, more details about the tingle sensation are available here. http://direct2dell.com/one2one/archive/2007/04/24/8522.aspx [direct2dell.com]
  • by PhotoGuy ( 189467 ) on Thursday January 17, 2008 @09:54PM (#22088714) Homepage
    Reminds me of a trip to Cuba last year. The power in the rooms was 220v, with no ground plug. Many consumer electronics, including my wonderful little Toshiba Libretto (now *that's* a sub-notebook, Apple) work fine on 220, the switching power supply just regulates it properly.

    However, I had to bend the ground pin out of the way to plug it in. Things charged and worked fine. However, apparently the brushed aluminum case wasn't quite at true ground with this arrangement. It was more than tingly (if your feet were on the ground; if you lifted them, it was fine). I made a point of only using the power supply to charge it, then use it on battery power, for safety's sake.

    It was interesting to see the cavalier attitude towards electricity down there. A worker was doing some construction with an electric drill outside our room; the drill obviously only took 120v, as he hooked up a transformer in our *bathroom* (which was near the door) to power his drill. It was connected to the plug with wires jammed into the outlet, and to the drill by wires wrapped around the prongs. Scary stuff. We stayed clear of our room that day. :) Check out the photos. [gass.ca]

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