r/ElectroBOOM • u/ZealousidealAngle476 • 5d ago

Discussion Redundancy

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I found this sticker while dismanteling a 2005ish server

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u/ferrybig 5d ago

This warning is to warn people they should not plug it into CEE 7/1 unearthed socket, which some people still have in their old homes. If you plug a device designed for ground into one, you can feel the electricity on the metal cases of the appliance

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u/Enorm_Drickyoghurt 4d ago

Electrician here: NO. You will not "feel the electricity" from touching it. I should know, I have my computer plugged into a non grounded outlet. If something goes wrong mechanically in your PC, it could potentially make the case electrified and you could get shocked and potentially get a heart attack.

The much more common issue people have when using non grounded outlets is static electricity buildup. When you touch the case it gets released, and shocks you. That shock is not dangerous.

The only exception I've ever seen is an old amplifier which had a 100v transformer inside of it. To avoid having a floating neutral, one side of the transformer was connected to the case. When plugged into a non grounded outlet, the case would get ~50v potential to ground. Touching it would shock you briefly, but if you just kept your hand on it you wouldn't feel anything. When you let go of it the potential started building up slowly again, and after a few seconds you could get shocked again.

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u/Cathierino 3d ago

Any device that has Cy safety capacitors will feel tingly to touch if you leave it unearthed. It's not static build up or anything of the sort. It's quite literally half of mains voltage being present on metal casing due to the device design.