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Thread: Every metal part of a cable component, usb port, etc. causes a shock when touched.

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    Question Every metal part of a cable component, usb port, etc. causes a shock when touched.

    I understand this is a problem of grounding but I don't know what part of their setup needs to be addressed so I'll just explain it as I saw it (and my knowledge on basic electronics is really flaky so pardon in advance)

    I live in the Philippines and I was over at my brother's apartment to do some maintenance on his computer. Clean out dust, replace computer fans etc. Anything from the mobo backplate, to screws, usb ports etc if you touched it you'd get a shock. Even if the PSU was switched to off you'd still receive a shock (even after pressing the power button on the computer and draining energy).

    It wasn't just the computer though when I got shocked by one end of the DisplayPort cable while it was connected only to the monitor.

    The apartment is brand new and construction was finished bout a month or two ago (construction started bout 2 years ago supposedly). All the wall outlets have nothing but 2 prong (which upon asking around apparently is normal).

    So my brother's setup is an AVR (Voltage Regulator) connected to the wall outlet (the AVR is a 2-prong btw), then by a power strip w/ 3-prong connected to the AVR followed by monitor etc.

    I dunno where to start as far as trouble shooting goes. Does an AVR provide grounding even though it only has a 2-prong (something tells me I doubt it) despite the fact one of the outlets on the back of it is a 3 prong?

    Just asked him just now to take a picture of the front and send it to me so here.
    https://cdn.discordapp.com/attachmen...126_193155.jpg

    https://www.omniphilippines.com.ph/product/wed-350-pk/ power strip.

    Thanks in advance!
    Last edited by Axel Daemon; 11-27-2019 at 01:28 AM.

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    Using an AVR or surge strip does not create a ground. AVR only bucks and boosts voltage and if the power strip isn't grounded, it's not going to be able to suppress surges because those are supposed to be diverted to ground. So right now, both of these devices are completely useless.

    Not using a ground wire in the Philippines is not "normal". It's the builder cheaping out on copper.

    First thing I would do is take off the face plate of the plug and make sure there is no ground wire in the composite cable feeding the outlet. Odds are against it, but wouldn't it be nice if the ground wire is there, but the electrician just didn't buy grounded outlets?

    If there is no third wire, look at the studs of the apartment. Are they metal or wood? If they're metal, you can replace the outlet from a 2 prong to 3 prong and fasten the ground wire to the stud.

    A common thing to do for ground is to run a wire to a radiator, but I doubt you guys use radiators in the Philippines. So the next thing to do is to run a wire all the way to the breakbox (the electrical panel). Even if the outlets in the house aren't grounded, the panel MUST be grounded. If the panel is not grounded, call the police because the apartment doesn't meet code and you have a serious fire risk. Modern breakers can't even trip if there's no ground. Back in the day, fuses were used. But we're not "back in the day".

    Inside the panel, there should be an individual, thick copper wire running through a hole in the cabinet and onto a "grounding bar".

    Of course, a real ghetto way to do things is to just go outside, drive a long iron spike into the ground with your ground wire wound around it and run that up to the outlet that the PC is plugged into, but now we're just getting silly.

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    Axel Daemon (11-27-2019)

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    Thanks for the advice! I'll see what I can do (and hopefully people will listen and not shrug it off as a nuisance).

    Even if I solve the grounding problem it's not going to actually do anything if the AC plug for the AVR is a 2-prong only right? Or can some 2 prong female to 3 prong male adapter work? (Actually that sounds really silly and wouldn't make sense since it's not making any actual contact to ground)

    If that doesn't work my only guess is to have the AVR replaced. (Probably a good time too, that thing is well over 6 or hell maybe even 10+ years old and makes a really loud humming noise at intervals).

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    Get rid of the AVR.

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    As in don't get a replacement?

    If you meant replace. The setup chain I mentioned previously is fine right? (Outlet > AVR > power strip?)

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    Quote Originally Posted by Axel Daemon View Post
    As in don't get a replacement?

    If you meant replace. The setup chain I mentioned previously is fine right? (Outlet > AVR > power strip?)
    Well, why do you have the AVR? What PSU do you have? Do you have a 230V only PSU and the mains voltage often drops below 190V?

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    I myself don't own one for my computer (just a power strip with surge protection). My brother on the other hand has had that AVR given to him from our dad and neither of us questioned it I suppose.

    He has a 500W Cougar PSU that's 110-230V, though you need to flip a red switch in the back to set the voltage (which on that note I need to replace the PSU in the near future with a better quality one) and I have no idea if the voltage drops or not. Upon looking up the basic gist of AVRs I suppose it's not needed in this scenario haha. When you put up questions like that for me to ask myself it helps put clarity into things . Thanks either way.
    Last edited by Axel Daemon; 11-27-2019 at 12:08 PM.

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    Quote Originally Posted by Axel Daemon View Post
    He has a 500W Cougar PSU that's 110-230V, though you need to flip a red switch in the back to set the voltage
    Yeah. That's a pretty shitty PSU.

    Back to the AVR: Pretty sure he doesn't need one. Get a better PSU and he definitely doesn't need one.

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    Default Every metal part of a cable component usb port etc causes a shock when touched

    You would need schematics of the circuits used to charge the battery. Also knowledge of how USB cables transfer energy. Why are you so sure youd need to modify a USB cable and not something else?

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