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USB shock hazard!?

 
Monu Tripathi
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I attached HTC HERO to the USB drive of my Desktop PC and felt a mild shock (have noticed this in laptops too). I wonder if you actually can get electrocuted...
 
Ankit Garg
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Electrocution by USB, that's new
 
Pat Farrell
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Are you sure it wasn't just a static discharge? USB is defined as 5V and no more than 500 milliAmps. That's less than a 9v battery can deliver.
 
fred rosenberger
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if you put a 9v on your tongue, it feels like an awful lot! I wouldn't dismiss that quite so casually.
 
Pat Farrell
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fred rosenberger wrote:if you put a 9v on your tongue, it feels like an awful lot!

Yeah, I used to do that as a kid.

But usually, the skin's normal resistance won't allow noticeable current to flow at voltages under 12V or so. Your tongue is wet and has salts so its a lot more conductive.

The numbers are pretty amazing, just a couple of volts and a few hundred miliamps across your heart will kill you. But usually humans don't push electricity across their own hearts.

If your hands are wet, or worse, wet with salt water, then things are different.
 
fred rosenberger
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Pat Farrell wrote:Yeah, I used to do that as a kid.

Kid? I do it now...it's the easiest way to tell if the battery is still good or not.
 
W. Joe Smith
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Pat Farrell wrote:

The numbers are pretty amazing, just a couple of volts and a few hundred miliamps across your heart will kill you.



I think it is 6 milliamps...or was it 60? I know it was very low. Which is crazy because at my old job I had to hook up power cables to a 400 amp company switch on the stage to power all the lights and stuff.
 
Pat Farrell
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Yeah, don't quote me on the exact milliamp value, its really low. I remember it was lower than the 100 milliamps that a standard "watch" battery, such as a CR2530 can deliver.
 
Ryan McGuire
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fred rosenberger wrote:
Pat Farrell wrote:Yeah, I used to do that as a kid.

Kid? I do it now...it's the easiest way to tell if the battery is still good or not.


9 volt battery. Feh.

Previous discussion
 
Vikas Kapoor
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Might be because of improper earthing? Did you face the same issue with your fridge/TV?
 
Frank Silbermann
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Monu Tripathi wrote:I attached HTC HERO to the USB drive of my Desktop PC and felt a mild shock (have noticed this in laptops too). I wonder if you actually can get electrocuted...
I'm sure you can. See:

http://www.youtube.com/watch?v=xz3u8IsHCB8
 
Monu Tripathi
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Vikas Kapoor wrote:Might be because of improper earthing? Did you face the same issue with your fridge/TV?

No
 
Deepak Bala
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Monu Tripathi wrote:
Vikas Kapoor wrote:Might be because of improper earthing? Did you face the same issue with your fridge/TV?

No


You need to bury your laptop under 1 feet of top soil to ensure proper earthing. Did you do that ? No ? Thought so
 
Vikas Kapoor
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Deepak Bala wrote:
Monu Tripathi wrote:
Vikas Kapoor wrote:Might be because of improper earthing? Did you face the same issue with your fridge/TV?

No


You need to bury your laptop under 1 feet of top soil to ensure proper earthing. Did you do that ? No ? Thought so


That would only solve laptop issue. I have complete solution.

      
 
Deepak Bala
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This is also becoming a popular technique to avoid shocks

 
Monu Tripathi
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Deepak Bala wrote:This is also becoming a popular technique to avoid shocks


and allergies too!

You are also using it to hijack this thread and post images of your secretary playing in mud!
 
Consider Paul's rocket mass heater.
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