Re:How can I avoid my MacBook Pro giving me minor shocks?
by bschwindHN on Monday November 14, 2016 @12:14AM
(#12947707)
> and scary to think that two-prong outlets and appliances are legal anywhere
In Japan, two prong outlets make up the vast majority of sockets, it kinda sucks.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by kalleboo on Monday November 14, 2016 @12:30AM
(#12947749)
I don't think I've ever seen a three-prong outlet in Japan (maybe only new installations?), but "earth screws" are quite common (any room prepared for an air conditioner will have one at least) http://www.hakusui-trading.co.jp/safety/img/img02.jpg
Re:How can I avoid my MacBook Pro giving me minor shocks?
by Teever on Monday November 14, 2016 @01:57AM
(#12948002)
What? That's crazy looking! Why not just put the third prong in there if it's wired up to handle a screw?
What's the point?
Re:How can I avoid my MacBook Pro giving me minor shocks?
by Too on Monday November 14, 2016 @03:07AM
(#12948261)
Just guessing here but I think it's to allow easy grounding of old appliances and other equipment that might risk contact with electricity but are not grounded by default. Metal frame desk as example.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by LaurentVB on Monday November 14, 2016 @03:59AM
(#12948462)
Very clever actually.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by kalleboo on Monday November 14, 2016 @07:01AM
(#12949236)
And the cable on the left here is what the included Apple MacBook power cable looks like, with the little earth wire sticking out to screw on http://rinare.com/wp-content/uploads/image_archive/110801_2....
I think it's just a legacy thing - historically, the only things that needed grounding were static appliances like fridges, washing machines and air conditioners. The manual in our fridge has this instruction for earthing http://mayoyo.tokyo/jIe.jpg
I need to revise my comment that "I don't think I've ever seen a three-prong outlet in Japan", because now that I have power sockets on my mind, I just saw a three-prong outlet at my gym. So I guess newer buildings have them.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by bschwindHN on Tuesday November 15, 2016 @12:20AM
(#12955809)
They're starting to become more common in newer apartments. For some reason my apartment has one outlet panel with two of the three-prong outlets, but the rest are two-prong. Except for the air conditioner and laundry machine sockets, which have the earth screw like you described.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by dsfyu404ed on Monday November 14, 2016 @08:13AM
(#12949570)
120v isn't going to hurt you, just scare you. You have too much resistance.
Re:How can I avoid my MacBook Pro giving me minor shocks?
by madshiva on Monday November 14, 2016 @08:46AM
(#12949755)
You can die with 50V. It's not the voltage that is important but the amps.
You can also die if you stick your finger for a long time (24H) in a small current.
http://electronics.stackexchange.com/questions/19103/how-muc...
Once all the outlets were rewired to be three-prong, with ground, I used a three-prong power cord and the problem went away.
Pretty scary feeling, and scary to think that two-prong outlets and appliances are legal anywhere. I'd also be surprised if Apple hasn't been sued at some point by someone getting electrocuted when using their laptop and a non-grounded, two-prong power cord.