Is grounding my issue?

Thread Starter

Leeadama

Joined Aug 22, 2016
3
I'm American military living in South Korea and I have not been able to find a good answer after several hours of searching with this question. I have no background or formal education with circuits and therefore my understanding of most items on this topic is fair at best.
I've been in my off-base apartment for 2 weeks with no problems. About 3 days ago, my laptop started to slightly vibrate when plugged in. When I closed the lid and put it in hibernate, it would not vibrate anymore. Then a few days later it would vibrate when hibernating.

I use the transformers provided with my apartment which is 2 prongs and brings down the 220v to 110v and I have a 3-pronged powerstrip plugged into the transformer, which I then plug in my 3-pronged laptop power cable. I tried different outlets and different transformers in my apartment with the same result.

I brought my laptop on base with the US standard electricity and the vibration did not occur. So from this, I also know it's not my laptop charging cable. From searching online, many posts said it is likely a grounding issue.

Any input given would be greatly appreciated. Thank you.
 

SLK001

Joined Nov 29, 2011
1,548
I brought my laptop on base with the US standard...
US standard? All the laptop power supplies that I have seen in the last 10 or so years have been world-wide capable. They are switchers, so the input range is 90-240V and 50-60Hz.

Look at the power adapter's label and post what it says here. You probably can plug it directly into your apartment's outlets (get rid of your step-down transformer).
 

tcmtech

Joined Nov 4, 2013
2,867
About 3 days ago, my laptop started to slightly vibrate when plugged in. When I closed the lid and put it in hibernate, it would not vibrate anymore. Then a few days later it would vibrate when hibernating.
It's a physical problem not an electrical one.

Either you have a cooling fan that went out of balance for any number of reasons or a hard drive is failing.
 

Thread Starter

Leeadama

Joined Aug 22, 2016
3
I am confident it is not the fan on the laptop. It is a distinct vibration when I lightly drag my fingers across the top of its metal chasis. My laptop is a Asus Zenbook pro that is only a few months old. And again, it does not vibrate when plugged into the outlets on the American base.

Attached is a photo of the transformer. As you can see, the wall is 2-pronged and I would not be able to plug in my laptop directly to the wall.
 

Attachments

GopherT

Joined Nov 23, 2012
8,012
I'm American military living in South Korea and I have not been able to find a good answer after several hours of searching with this question. I have no background or formal education with circuits and therefore my understanding of most items on this topic is fair at best.
I've been in my off-base apartment for 2 weeks with no problems. About 3 days ago, my laptop started to slightly vibrate when plugged in. When I closed the lid and put it in hibernate, it would not vibrate anymore. Then a few days later it would vibrate when hibernating.

I use the transformers provided with my apartment which is 2 prongs and brings down the 220v to 110v and I have a 3-pronged powerstrip plugged into the transformer, which I then plug in my 3-pronged laptop power cable. I tried different outlets and different transformers in my apartment with the same result.

I brought my laptop on base with the US standard electricity and the vibration did not occur. So from this, I also know it's not my laptop charging cable. From searching online, many posts said it is likely a grounding issue.

Any input given would be greatly appreciated. Thank you.

South Korea outlets are 220V at 60Hz. The power supply and cord set in your photo can be plugged directly into the wall socket in South Korea. You don't need the transformer box in the other photo.

You can use the simple plug adapter without a transformer. The simple plug adapter only changes the connector type - not the voltage. They normally cost less than $10 in the US and can be found at Asian hotels for $2 to $10 - just go to a business hotel nearby and ask if they have one for a US plug. Otherwise, they may be available at the PX.

The combination of the "switch mode power supply" (brick on your laptop cord) operates at one frequency to create the 19V your laptop needs using a pulse (switching) method. The transformer box that you bought to create 120V from 220V also uses a switching Method and the two frequencies can cause "beat frequencies" that feel like vibrations. Skip the 220 to 120v transformer box - it is just creating confusion of the switch mode supply on your lappy's cord.

Good luck.
 
Last edited:

Kjeldgaard

Joined Apr 7, 2016
470
The phrase "It is a distinct vibration jeg lightly drag my fingers across the top of its metal chasis." sounds like the small, and usually harmless, leakage current through the power supply noise filter.

If I am right, in that you have two power outlets of the German Schuko type that can be seen above the transformer on the left image in post # 7, then you should be able to find an adapter that connects the ground-pin through, or if the power supply has a detachable cable so you can obtain a "European cable" instead of the adapter.
 

Thread Starter

Leeadama

Joined Aug 22, 2016
3
I picked up an adapter with the ground pin and the vibration has stopped. Thanks for the input everyone and I truly appreciate everyone taking the time to help me find a solution. Take care.

So say we all
-Lee Adama
 
Top