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My computer zaps me with strong zaps which can get quite annoying. So I need a way to Earth (ground electrically)my laptop.

Is there any danger (for me or my laptop) in connecting a crocodile clip from my laptop case to the earthing (ground) wire at the wall (Spanish wall socket) and will that solve the problem?

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    never, never mess with mains power - seek professional repairs!
    – user375162
    Oct 7, 2014 at 10:52
  • I would suggest taking your Laptop to a repair shop or something to see where the current is leaking from for this issue to occur before trying to fix it yourself. Sounds like something you should not be trying to fix without professional help first.
    – DarkEvE
    Oct 7, 2014 at 10:53
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    Do you get zapped only by your laptop? If you Laptop has a power issue you should seek professionals, like Omen said. But it may be that you are statically charged, not your laptop. Are you on a carpet? With socks?
    – ap0
    Oct 7, 2014 at 10:53
  • It was one pulse zap, or longer zapping? What laptop brand is this?
    – Kamil
    Oct 7, 2014 at 12:58

2 Answers 2

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There are two possibilities here.

One is that you are building up a static charge when walking across your carpet, sliding off of or onto your chair... something like that. When you touch metal on the laptop you are discharging that static charge. Does it happen more than once? If not, it's this sort of issue. The laptop is already providing a ground, so adding a grounding wire won't help.

What should help is grounding yourself to something else, preferably something with a high-resistance path to ground, before touching the laptop. Discharging through the resistance will cause it to happen gradually, so you won't feel the spark. One megohm or so is a good choice (this is typically what's in the anti-static grounding straps). If you don't know what that means, get a friend with good electronics construction knowledge to help you.

The other possibility is that the AC adapter of the laptop is "leaking" AC onto the laptop's chassis. If you feel it every time you touch whatever it is that you're touching, it is this sort of problem. This is an extremely dangerous situation, and it will not get better on its own. The cure is to replace the AC adapter... Preferably before you ever use the laptop again.

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    Jamie, thank you very much for your very detailed answer. The comments box is too small to post the other possibility which I discovered so I have created a new answer. Your knowledge is much greater than mine in this area so please correct me if any part of it is invalid.
    – Stack Man
    Oct 7, 2014 at 21:28
  • I would just like to point out that even in 2018, not all chargers use a grounding pin. And in fact, when I disconnect my charger, the zapping stops, when I reconnect it the zapping continues again. For me it's pretty clear that this problem has to do with the charger. But I'm wondering if it may be related to the fact that mine does not even have a grounding pin.
    – bvdb
    Feb 21, 2018 at 20:59
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Jamie Hanrahan gave an excellent answer but I think there is another possibility apart from what he described. It seems that many people have zapping issues with their laptops and the zaps seem to be more than just static. See this page for a lot of examples

From that same page, a user responded with the following (and I quote):

"If you have the laptop in your lap, and if you are wearing shorts, the areas of your legs that are in contact with the screws will feel uncomfortably tingly - like there are pins being poked into the surface of your skin, but not deeply. The sweatier you are, the more galvanic reaction (the more it hurts). This is NOT a power supply problem, so getting another DC power supply is not going to cure the matter.

What this is, is the AC voltage that is sinked to ground through a number of circuits that rely on higher voltages stepped up through DC to DC converters (see: http://en.wikipedia.org/wiki/DC-to-DC_converter). Displays take higher voltages to operate. An oscillator converts the laptop's DC voltage to AC, steps up the voltage, rectifies it, then filters it. This is the residual AC voltage from that process. It is a byproduct of miniaturization and not having enough space for adequate shielding or having an adequate groundplane. You become part of the ground and might be a better ground than the rest of the device.

As the OP stated, 48 mA is usually not enough to disrupt your heart's electrical activity, but it is a big discomfort. At first, I used a book under the laptop. Then I took some black electrical tape and put it over each of the screws on the bottom of my Dell. It works, but then, the laptop also gets hot. That's another issue."

Connecting a crocodile clip between my network cable and a ground did fix the problem...HOWEVER AS MENTIONED BY OTHERS, YOU SHOULD NEVER MESS WITH ELECTRICITY WITHOUT PROFESSIONAL HELP. For example, if the AC adapter is leaking AC (as suggested by Jamie) and you touch the crocodile clip, YOU COULD BE ELECTROCUTED.

Here is a page describing similar ways to ground your laptop. AGAIN, ALTHOUGH IT MAY APPEAR SAFE, IT CAN BE VERY DANGEROUS TO EXPERIMENT WITH THESE DESCRIBED METHODS WITHOUT PROFESSIONAL HELP.

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  • That's a possibility. If you have a scope you can look at the "residual AC voltage" - if it's much higher than 60 Hz (for things like LCD backlights it'll be in the 10s of kHz range) then this is the culprit.
    – Jamie Hanrahan
    Oct 7, 2014 at 23:00
  • OK - I have accepted your answer as the main answer and then perhaps some people will find my answer useful as a subsidiary. Thank you very much for going into so much detail to help everyone understand.
    – Stack Man
    Oct 7, 2014 at 23:03
  • And re "you could be electrocuted", yes. It is an interesting bit of irony that while grounding an AC-operated device's case can help prevent shocks that would be due to live-to-chassis leaks within that device, grounding can also introduce an exposed ground point into the environment - which will make leaks in other equipment more dangerous! This is one reason why it is important to find out what is really causing the problem, and fix it, rather than just trying things until something works.
    – Jamie Hanrahan
    Oct 7, 2014 at 23:04
  • Yes, it was my first impression that grounding is safe no matter what...it was only after talking to some more educated friends that I realised the massive error. Lesson here - never NEVER mess with electricity unless you are a trained professional.
    – Stack Man
    Oct 7, 2014 at 23:08
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    And then there's something called "touch current": very low-level AC power-to-chassis leakage. It's usually felt as a sort of "fuzziness" as you run your finger over an exposed metal surface (caused by the AC current making your muscles twitch by tiny amounts). I've often felt it on the chrome-plated edge strips of fluorescent-lit display cases. Some people are more sensitive to it than others. It's usually a sign of either defective double-insulation or an improperly grounded chassis, and of course should be repaired; it will never get better by itself and may get worse.
    – Jamie Hanrahan
    Oct 7, 2014 at 23:11

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