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hanguolaohu

macrumors regular
Original poster
Mar 5, 2007
139
1
I'm using a USA Macbook Pro in China and noticed that when I plug in the power which is 220 volts the laptop vibrates. I do not feel this vibration while I use my laptop in the USA which uses 110 volts. I've also had problems with my USA hard drives vibrating and even Final Cut Pro being very unstable while using it in China. I was wondering whether this vibration is normal and whether it could possibly harm my laptop. Any info would be much appreciated!

HL
 
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I think I know what you mean - do you mean you can feel a kind of low level vibration when you move your finger across the aluminium case?

If so, I think it's an earthing problem.

I bet you are using your US adapter with a mains multi-adapter plug thing with no earth connector.

I get this going the other way actually, from UK to US using an adapter. If I don't use an adapter plug but borrow a US lead for the power supply this phenomenon goes away.
 
I think I know what you mean - do you mean you can feel a kind of low level vibration when you move your finger across the aluminium case?

If so, I think it's an earthing problem.

I bet you are using your US adapter with a mains multi-adapter plug thing with no earth connector.

I get this going the other way actually, from UK to US using an adapter. If I don't use an adapter plug but borrow a US lead for the power supply this phenomenon goes away.

I'm using my new (june 2009, 15", 2.8Ghz) macbook pro (bought in Canada) in Vietnam. I am feeling this too when i move my finger across the aliminum case but not all the time. only when connected from some power sources.

Otherwise i cannot say i feel any vibration from the laptop that seems unusual as the OP might be describing
 
Exactly. But I took my laptop to my work today which is in an old house, and the vibration feels especially strong, which makes me concerned whether it could be harmful. Yes, I'm using a USA adapter with the 3 prong connection. Hm, I guess I could get a China adapter, but as long as this doesn't harm my laptop I'm wondering whether it's necessary. This has adversely affected some of my American external hard drives with power supplies rated from 100-240v, but they still had instability when using Final Cut Pro.
 
You're probably feeling a slight tingling due to currents going through the case. Make sure it's grounded properly.
 
You're probably feeling a slight tingling due to currents going through the case. Make sure it's grounded properly.

Yeah, I'm sure the Macbook case is floating relative to ground. The power suppy is no doubt isolated from ground for safety reasons, but there's probably a leakage current there - you could try an isolating transformer between the AC mains supply and the Apple PSU. Or sit on a rubber mat and avoid contact between any part of your body and any conductor/the floor/metal tables...

This is most likely to occur in countries with a floating neutral (LNE)
 
I just returned home, which is a much newer building and I don't feel the vibration anymore. I think I should get the circuits checked at my workplace. I appreciate all the helpful info!
 
You probably should get a portable surge protector, or even a "travel adaptor" kit to step it down to 110.
 
You probably should get a portable surge protector, or even a "travel adaptor" kit to step it down to 110.

That is not necessary. The Magsafe will work off 110V or 220V just as well.

You could buy an inexpensive ground tester that will tell you if the building is properly grounded. Make sure you get one for the right voltage (buy it in the country where you are using it to be sure).
 
There are many many threads on this going back to the very first metal mac notebooks. Basically if your not running it on 110(120)v 60Hz it seems common to get vibration or light shock. Its funny reading these thread though. B/c if your from the US, the thought of plugging any computer or appliance into a 220v receptacle is Crazy.
 
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