Static electricity

lazypoet

macrumors regular
Original poster
Jun 9, 2015
212
43
So I got my new 2017 macbook pro 15 inch macbook pro in the mail today (YAY), but I've noticed static electricity on the surface of the macbook pro when I rest my hands on it. Is this normal?

The Macbook Pro didn't come with an extension cable, which surprised me. I've heard the extension cable grounds better the electricity. So can I/should I use my 2010 macbook pro extension cable on my new charger?
 

jerryk

macrumors 603
Nov 3, 2011
5,706
2,854
SF Bay Area
So I got my new 2017 macbook pro 15 inch macbook pro in the mail today (YAY), but I've noticed static electricity on the surface of the macbook pro when I rest my hands on it. Is this normal?

The Macbook Pro didn't come with an extension cable, which surprised me. I've heard the extension cable grounds better the electricity. So can I/should I use my 2010 macbook pro extension cable on my new charger?
Do you feel this when it is not plugged in?

MacBooks, and other computers, will bleed current (tingling sensation when touching them) when they are charging. But when you unplug the charger it stops.

If that is what you are feeling it is normal.
 

lazypoet

macrumors regular
Original poster
Jun 9, 2015
212
43
Do you feel this when it is not plugged in?

MacBooks, and other computers, will bleed current (tingling sensation when touching them) when they are charging. But when you unplug the charger it stops.

If that is what you are feeling it is normal.
It's when it's plugged in (without extensions cord).

My 2010 Macbook Pro never has this (plugged into the same outlet). So I'm thinking it has something to do with the lack of an extension chord on the new model.
[doublepost=1500316762][/doublepost]I took the risk and plugged it in with my old extension chord and now the static electricity is gone. I recommend this to anyone experiencing this :)
 

jerryk

macrumors 603
Nov 3, 2011
5,706
2,854
SF Bay Area
It's when it's plugged in (without extensions cord).

My 2010 Macbook Pro never has this (plugged into the same outlet). So I'm thinking it has something to do with the lack of an extension chord on the new model.
[doublepost=1500316762][/doublepost]I took the risk and plugged it in with my old extension chord and now the static electricity is gone. I recommend this to anyone experiencing this :)
Usually a grounded plug will get rid of that effect. It is harmless, but a bit annoying.
 

Populus

macrumors 65816
Aug 24, 2012
1,162
990
Valencia, Spain.
I've always used my 2010 MacBook Pro plugged with the regular cable, without the extension cord. Thus, I've always felt that electric deeling when touching the aluminum. A bit annoying, but it has been this way since Jobs times.

My 2010 MBP does that. My 2015 MBP does it too. The new 2016 MBP has that feeling too.
A bit annoying, yes, but is completely normal :)
 

lazypoet

macrumors regular
Original poster
Jun 9, 2015
212
43
I've always used my 2010 MacBook Pro plugged with the regular cable, without the extension cord. Thus, I've always felt that electric deeling when touching the aluminum. A bit annoying, but it has been this way since Jobs times.

My 2010 MBP does that. My 2015 MBP does it too. The new 2016 MBP has that feeling too.
A bit annoying, yes, but is completely normal :)
So there is absolutely no harm being done to the mac with the constant static charge? I thought static electricity was bad for hardware.
 

Stefan johansson

macrumors 65816
Apr 13, 2017
1,294
607
Sweden
So there is absolutely no harm being done to the mac with the constant static charge? I thought static electricity was bad for hardware.
Static charges need to be rather powerful to damage a laptop,as the internal components is protected,and the light power leak that gives the ticklish feeling is actually not static electricity,it's power leak from the internal power relay. As it's only low voltage,it's clearly harmless,and a better cable with ground connection will solve it.
 

MC6800

macrumors 6502
Jun 29, 2016
368
126
So there is absolutely no harm being done to the mac with the constant static charge? I thought static electricity was bad for hardware.
Technically what you're feeling is an alternating electric current, not static electricity. Static electricity is a stored charge, and would only be transferred on the first touch, often as a small spark (and yes, it's bad for the internal circuitry, but that's protected by the conductive case).

The current you're feeling is the 120V (or 240V) AC from the wall socket, but greatly limited by internal impedance of the AC adapter and resistance of your skin. It's due to your computer's floating ground. Here's a discussion of the effect.
 
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elf69

macrumors 68020
Jun 2, 2016
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Cornwall UK
my 2007 macbook pro 17" and 15" both do this But I have an apple power cord so use I use it on these.

my 2012 macbook air does NOT do this though, possibly due to lower power PSU.
And my 2010 macbook is plastic so no issue there.

Another very very good reason not to use 3rd party chargers as the locating pin for tip or cord is usually plastic and not an earth point.
 

Stefan johansson

macrumors 65816
Apr 13, 2017
1,294
607
Sweden
my 2007 macbook pro 17" and 15" both do this But I have an apple power cord so use I use it on these.

my 2012 macbook air does NOT do this though, possibly due to lower power PSU.
And my 2010 macbook is plastic so no issue there.

Another very very good reason not to use 3rd party chargers as the locating pin for tip or cord is usually plastic and not an earth point.
Exactly how the charger is made,depends on legal regulations in the area where it's sold. For example,a US charger would definitely not work in the 240V AC networks in most of Europe.
 

Stefan johansson

macrumors 65816
Apr 13, 2017
1,294
607
Sweden
of course.

but worse case any 2 pin mains lead will fit the mac chargers.
Probably,but here,MacBooks sold at Apple resellers are usually delivered with two power cables with different wall plugs,one grounded and one not. At least mine was like that,due to the facts that many users in rural areas around here use grounded wall sockets as a part of their protection against thunderstorms. I'm not sure if it will protect the computer,but it would hopefully prevent a fire caused by a plugged in heater,coffee machine or floor lamp.
 
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