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Earlier quoted context omitted.
The 70v is probably induced voltage at milliamp levels. You can fix it by bonding the neutral to ground at the breaker box.
This is potentially deadly advice. A neutral/grounding fault will energize all your home devices with live potential; same with a live/neutral swap (unlikely but possible with Indian wiring standards).
I have this problem in India. I suspected the mains was dodgy, because during the many power outages i never got the shocks when on UPS. I got a multimeter and measured. The neutral was 70V and the phase 300ish. So the difference was roughly 230V but a switched power adapter would make this hover around 70 too (I believe an old coil based would probably been fine). The Indian electrician didn't understand my problem…
I had the same problem in Australia. I thought it was just me being over-sensitive to static electricity
I had a grounding issue and I used to get shocked by my tower all the time, this is pretty common.
Earlier quoted context omitted.
This is potentially deadly advice. A neutral/grounding fault will energize all your home devices with live potential; same with a live/neutral swap (unlikely but possible with Indian wiring standards).
> This is potentially deadly advice. A neutral/grounding fault will energize all your home devices with live potential; same with a live/neutral swap (unlikely but possible with Indian wiring standards). You are wrong. In the US the NEC requires this. If you bother to look inside your breaker panel you will find the neutral and ground wires are literally screwed down to the same bus bar. Any path your body (or the so…
It could be different in US, but in modern European installations the PE and N bars are separate; older installations use common PEN; and even older ones don't even have PE. Each of the wiring schemes requires different approach and poses different hazards. There's no single recipe that would work on all of them.
My bottom line is: don't make arbitrary connections in the breaker box without proper knowledge and training; and don't give random electrical advice on the internet without knowledge of local codes.
https://www.amazon.com/Sperry-Instruments-GFI6302-Outlet-Tes...
If this says good (two amber lights) and you're still getting shocked, follow up with a voltmeter and/or qualified electrician.
Ungrounded adapter + bad mains power = zap! Ungrounded adapter + clean mains power = probably no zap Grounded adapter + bad mains power = probably no zap Grounded adapter + clean mains power = no zap It's not just the adapter and it's not just the mains power; it's when both come together. Electricity follows pretty simple rules when it comes down to it. Always always always ground your A/C connections. Why wouldn't…
This became such a problem, he made his own ground by using a big metal pipe outside the house that was already deep in the earth, and running a wire from it to where he kept all his equipment.
Then he used stuff like in that picture to make sure he could ground all his equipment.
My understanding is that it's caused by Y capacitors in the power supply's EMI filter leaking minimal amounts of current onto the case. As others have mentioned, proper grounding usually fixes the issue - although in one case I had to rewire an entire apartment because someone had a very lopsided idea what the PE wire is for. It was for a friend with a metal Macbook Pro, an exceptionally sensitive skin, and way too m…
You can feel this effect for yourself by using the two pronged plug and finding something grounded to the chassis to touch. With one hand, hold the grounded item while moving the palm of your other hand around the backside of the led. It's a bit dependent on the conductivity of your hands but I've found most people can feel it, even my dad who's a farmer and has very dry hands. Remember, if you get electrocuted, it's not my fault, it's Apple's. They have much deeper pockets than me.
What's fascinating to me about this phenomenon is that you can actually feel the 60Hz AC by running your hand across the lid. It feels as if the surface is slightly bumpy, but the width of the bumps changes as you adjust the speed your finger moves. Unplug from mains, and the surface becomes smooth. As the answer notes, this only happens when using the two-prong adapter without earthing. It also seems to be more noti…
Well that explains what the weird feeling I used to feel when touching a 2015 Macbook I was using last year. It felt exactly like that (as though the surface was bumpy) though I never got far enough into debugging it to figure out that it was actual charge leakage onto the case and that I was feeling the AC current. That's a bit scary. Question: aren't laptops powered off DC (there's a rectifier/transformer combo in…
This is a common problem, the power cable from the power adapter to your laptop is also usually connected to ground, if the ground is hot then you get shocked.
Time to buy a 3 pin adapter!
What's fascinating to me about this phenomenon is that you can actually feel the 60Hz AC by running your hand across the lid. It feels as if the surface is slightly bumpy, but the width of the bumps changes as you adjust the speed your finger moves. Unplug from mains, and the surface becomes smooth. As the answer notes, this only happens when using the two-prong adapter without earthing. It also seems to be more noti…
Well that explains what the weird feeling I used to feel when touching a 2015 Macbook I was using last year. It felt exactly like that (as though the surface was bumpy) though I never got far enough into debugging it to figure out that it was actual charge leakage onto the case and that I was feeling the AC current. That's a bit scary. Question: aren't laptops powered off DC (there's a rectifier/transformer combo in…
However, the voltage measured from either pin to ground might very well fluctuate. Without the grounding pin on the power supply, the DC side of the supply may 'float' with respect to earth ground. If you plot the voltages measured from each pin to ground, it probably looks like a pair of sine waves, one shifted 20 volts above the other.