geekhack
geekhack Community => Keyboards => Topic started by: Marilyn lin on Tue, 02 March 2021, 01:29:39
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hi im new in this hobby just moved from a bluetooth office keyboard to a wired mechanical keyboard, i have an old computer i never plug anything to the usb port before except the bluetooth dongle before.
my PC and the electricity in my home has no grounding/ ungrounded i can feel it little shock electric on my PC case i just wondering is it safe for low voltage device like a mechanical kb? i never use any wired peripheral before even my headset and my mouse are wireless so i kind a bit worried about it
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That's not even safe for you or the computer much less the keyboard.
I would make sure you use a plastic body keyboard, not an aluminum model, but instead of a keyboard I'd consider spending that money on an electrician.
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I don't have grounded electrical sockets in most rooms of my house either. Lots of not-that-much older homes around here don't, and it has been discussed a lot on domestic computer forums.
There is no immediate danger but there is less protection against shorts, no. Eerie sensation when touching my PC's case though, which is aluminium.
The shielding around USB connectors do touch the PC's case, which are connected to the shielding around USB cables, which would transfer the eerie sensation to metal keyboard cases. So yes, do use keyboards with plastic cases!
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the keyboard will see no difference, for it it will see 0v (your floating ground) and 0 + 5V (floating + 5V) i have an old laptop powersupply with a failed separation and although the metal chassis of the laptop is at mains voltage (with really low current, and i have protection) the laptop itself sees not difference as its 19V is just riding that 220V sine. it is my 2nd powersupply with that PC that has that fault... both proper HP, the non HP one actually blew up, i'd rather have a tiny shock than a fire :)
(then again i have protection and i kinda know what i am doing, after the 1st shock i unplug the laptop before using it :))
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I don't have grounded electrical sockets in most rooms of my house either. Lots of not-that-much older homes around here don't, and it has been discussed a lot on domestic computer forums.
I realize it's common, there's also a reason we moved away from it.
The shielding around USB connectors do touch the PC's case, which are connected to the shielding around USB cables, which would transfer the eerie sensation to metal keyboard cases. So yes, do use keyboards with plastic cases!
Not all metal keyboards are grounded this way, most aftermarket cases are not and many boards are not (NK64 is not).
Any weird feeling that isn't static charge from you is a leak and that's not good.
You see that on aquariums a surprising amount (pumps and heaters usually) and it can kill you especially on marine aquariums. It's even worse if you use 220v in your country.
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It's safe for the Keyboard, it's just NOT SAFE FOR YOU. Without Earth Ground, in event of a serious short, lightning, local transformer blowing, etc, and you're touching any of the metal, YOU DIE.
(https://i.imgur.com/MkPDhU9.gif)
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Also, Grounding is really cheap to install, All it is, is a metal ROD, inserted into the ground and you put in some salt in the soil so that it conducts better.
The other option is have the ground ducted via a Thick conductor to the Metal water pipe MAINS that come into the house. Many houses are earth ground this way.
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Many houses are earth ground this way.
Although by the 1980s various forms of plastic were becoming common even for the supply coming from the street to the house.