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Computer isolation issue

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Andromel Posted messages 58 Status Member -  
Malcom911 Posted messages 849 Status Member -
Hello,
I would like to reach out to you regarding a computer that I built myself... It’s four years old, and for the past few weeks, I’ve been experiencing significant electrical issues with it. Indeed, we get “shocks” from the casing, and after a test, it’s evident that there’s a slight current running throughout the machine, on all components... It tingles the fingers even on the hard drives, the video card...

Initially, I did install the small washers to isolate the motherboard from the casing. Before I embark on a lengthy disassembly/check, I would like your opinion:

Where could this be coming from? I have already checked all my connections and I don’t see any wires contacting where they shouldn’t... However, the issue is becoming dangerous as I feel the slight electrical flow is even coming up through some of my external peripherals; it’s high time I act before something burns out.

I have several theories:
_ Could it simply be my power supply that is giving up?
_ Could a simple internal component reaching the end of its life cause this electrical flow?
_ Can a casing's isolation wear out over time and needs to be changed?
_ I’ve also noticed that my new graphics card, changed a year ago, has certain DVI “big” ports that tend to touch the edge of the casing’s notch... Is that it?

Finally, do you have a method to suggest for my disassembly to find the source and what kind of materials I could place in the casing to enhance its insulation?

Thank you in advance for your opinions!
Configuration: Windows XP Firefox 3.0.4

6 answers

  1.
    ac 3 Posted messages 2289 Registration date   Status Member Last intervention   841
     
    Of course it comes from your power supply, it's the only element connected to the outlet. Change it quickly before breaking everything.

    Have a good day
    --
    Courtesy allows us to communicate.
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  2. Malcom911 Posted messages 849 Status Member 44
     
    Have you changed the power socket for the PC?
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    1. ac 3 Posted messages 2289 Registration date   Status Member Last intervention   841
       
      I don't really see the connection; his PC has a leak between the phase and the case, changing the power outlet won't fix the insulation fault.

      Have a nice day.
      --
      Courtesy allows us to communicate.
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      1. Malcom911 Posted messages 849 Status Member 44 > ac 3 Posted messages 2289 Registration date   Status Member Last intervention  
         
        I'm saying this because I was a victim of the same problem and it was due to a faulty power outlet (so if there is a connection).
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      2. ac 3 Posted messages 2289 Registration date   Status Member Last intervention   841 > Malcom911 Posted messages 849 Status Member
         
        On a a power outlet, there is:

        A phase
        A neutral
        A ground in the best case

        If there is a fault in the ground wire (or no ground wire), it will highlight the insulation fault of the supply which has a leakage to the casing.

        If the ground wire has no failure, the flow of leakage current will occur through the ground wire connected to the computer case and we won't notice anything as long as this leakage current does not exceed the current tolerated by the differential circuit breaker, which is currently 500 mA in most electrical installations.

        Therefore, changing the power outlet can "mask" the problem.

        Have a good day.

        --
        Courtesy allows us to communicate.
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      3. Malcom911 Posted messages 849 Status Member 44 > ac 3 Posted messages 2289 Registration date   Status Member Last intervention  
         
        Yes, I speak well in the case where the socket does not have a ground!!!
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  3. Andromel Posted messages 58 Status Member
     
    I completely agree with AC3, especially since sometimes I plug a laptop into this socket instead and it doesn't cause any issues...

    Okay, thanks AC3, without wanting to overdo it, I don't know much about power supplies as I usually buy them with original cases...

    On sales websites, they mention modular (yes/no) and PFC (yes/no), what does that mean?
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    1. Malcom911 Posted messages 849 Status Member 44
       
      lol fortunately, the phone socket only has the live and neutral wires, it does not have a ground.

      anyway!!

      it's just an opinion.
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    2. ac 3 Posted messages 2289 Registration date   Status Member Last intervention   841
       
      PFC, power factor corrector.
      To make it simple, a modern switching power supply causes high-frequency disturbances on the EDF network, which it has a hard time managing; the PFC circuit is there to significantly reduce these disturbances.

      Modular in this context, I don't understand your question.

      Have a good day.
      --
      Courtesy allows us to communicate.
      0
  4. Andromel Posted messages 58 Status Member
     
    However, the plug of my laptop does have a ground pin, in any case, its plug is strictly identical to that of my computer...
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    1. ac 3 Posted messages 2289 Registration date   Status Member Last intervention   841
       
      Yes, but your phone has no insulation defects, so you don't get electrocuted when you touch the casing. This is a normal situation.
      --
      Courtesy allows us to communicate.
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  6. Andromel Posted messages 58 Status Member
     
    Yes, it was to respond to Malcom, I didn't see much difference between a laptop power supply and that of a desktop, the plug is exactly the same!

    Anyway, thank you, I will research power supplies in detail and change mine as soon as possible!

    I will mark the topic as resolved.
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  7. thomas
     
    Hello, I have exactly the same problem: "Indeed, we feel 'tingling' at the level of the case; after a test, it is evident that there is a slight current flowing throughout the machine, on all components... It tingles the fingers even on the hard drives, the video card..."

    I plugged my computer into a power strip with a switch. When I turn off the computer, I still feel the current; I tried switching the power supply switch to off, and the problem persists: I feel a kind of slight electric current when I rub my fingers.

    I then turned off the power strip, and there was no longer a problem... But as soon as I turn the power strip back on, the slight current returns...

    I noticed that there is actually no ground outlet in my room.

    Given that I feel current in every part of the computer, including the external hard drives, I'm starting to worry. What should I do?
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    1. Malcom911 Posted messages 849 Status Member 44
       
      It is necessary to pull a ground wire to another outlet that has one or to the panel.
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