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Comment by bigyabai | Hacker News Reader

I owned multiple Macbooks that built a positive static charge when they were on, instilling a Pavlovian fear of being shocked into anyone that used it. Those were fun.

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If you use the 3-prong version of the power adapter to connect to a grounded outlet, this problem goes away. Of course, Apple doesn't actually sell a 3-prong plug for their charger in Europe... so us lucky folks in the EU have to get a 3rd party one off the internet

Yes, they do. [1] for Italian outlets, [2] for many of the others. I'm sure I don't need to continue.

[1]: https://www.apple.com/it/shop/product/mw2n3ci/a/prolunga-per...

[2]: https://www.apple.com/fr/shop/product/mw2n3z/a/câble-d’exten...

I suspect what they meant is that there isn't an official Schuko nub that slides onto the brick and lets you hang it directly from the socket rather than carrying an extra meter of cable around. There is a BS1363 one, and those are only legit feasible in a grounded configuration (although I guess you could use a plastic ground spade to lift the child protection slider inside the socket if you were a particularly unpleasant engineer). Nice for those of us in British-adjacent countries.

I'm talking about the non-corded variants. Carrying an extra metre of cable around just to get the grounding prong is not great.

As another poster mentioned, it's particularly annoying because Apple does ship the UK adapter in 3-pin grounded form

YMMV. I throw away the non-corded variants because they rarely fit in the spaces that people think to put outlets, especially as the chargers have grown and (particularly) train operators love putting outlets attached to tables with about 5mm of clearance.

That’s nothing to do with static electricity, it’s capacitive coupling through the safety capacitors in the power supply. The chassis sits at 90vac or so as a result, it’s not a safety issue it’s FCC compliance for emitted noise.

Is this generally true for laptops / phones?

I've often wondered why I can tell by touch whether a device is charging or not from the slight "vibration" sensation I get when gently touching the case.

For ungrounded / 2-prong outlet devices, yeah.

It's often noticeable if you have a point contact of metal against your skin; sharp edge / screw / speaker grill, etc. Once you have decent coupling between your body and the laptop, you won't feel the tingle / zap.

They're called Y-caps if you want to delve deeper into them and their use in power supplies.

I get that too. I was wondering if it was just me.

They still do. My m1, m1max and m4max Macbook Pros all build a positive static charge. It isn't even something that renders it "returnable" because I observed it on every single Macbook in the last 4-5 years so I just assume that's just how Macbook Pros are now.

This hasn't changed in at least 2 decades: I was getting zapped by Apple metal laptops circa 2004. But I have never encountered this problem when using a grounded plug.

It was also a lot worse for me when plugged into outlets in an old house in Mexico, especially when my bare feet were touching the terracotta floor tiles; it's not really an issue in a recently re-wired house in California with a wood floor, using the same laptops, power strips, etc.

If you are having this issue and you currently plug a 2-pronged plug into a grounded outlet, try using Apple's 3-pronged plug instead, and I expect it would go away. If you don't have grounded outlets, then that's a bit more complicated to solve.

That's what confuses me, I am using the cable with three prongs, it is grounded. I am beginning to suspect some other appliance I am plugging into it that is responsible of the build-up of charge, but then why is it not finding its way to the ground... something doesn't add up but has been my experience consistently.

Perhaps the outlet isn't properly grounded?

Is there any laptop with a metal body out there that does not have this issue? I've had two RedmiBook by Xiaomi and both has that vibrating electric feeling to them when plugged in.

It's an artifact of the charger.

This comment explains it well: https://news.ycombinator.com/item?id=45686427

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