Static electricity and hardware

Soldato
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Hey lads,

I'm trying to gather some information on how static electricity will affect PC components. Now we all know that once a component has been subjected to high amounts of static electricity it will break. Now what isn't entirely clear is what damage a component with a static charge can do when placed into a working PC. My guess is that the charge that has been built-up will eventually degrade and cause no damage. I can't find a definite answer for this though. I'm hoping someone on this forum has experience with hardware they knew had a static charge and tell us how they dealt with it.

A storm with loads of lighting occurred this week and my PC stopped working afterwards (won't POST). I'm not sure if it was a surge or a spike or what. There's no burn marks on any components so the only thing that comes to mind is static (lighting is basically a form of static electricity isn't it?) therefore I'm very skeptical about putting anything from my old rig into a brand new rig.

Thanks for any input.
 
Soldato
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My guess is that the charge that has been built-up will eventually degrade and cause no damage.

Yes, but a static charge dissipates quickly

(lighting is basically a form of static electricity isn't it?)

Yes

therefore I'm very skeptical about putting anything from my old rig into a brand new rig.

Unless you rub the ram on your shirt before putting it in to the new one it will be fine... Chances are only 1 component is broken in your rig

RMA whats been broken!
 
Soldato
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Thanks for posting.

Well I've decided to upgrade anyway mate, she was getting old. I'm just hoping to salvage the optical drives and HDD. I imagine the data will be corrupt on the HDD but that isn't an issue.

How do you know static dissipates quickly? Do you have a source or just something you know? As a kid I remember having static in my monitor which stayed for ages. Let's just say the static did remain, would placing that component in an anti-static bag dissipate any charge that is in the component or do those bags simply prevent it from conducting the charge in the first place?

Edit:

Wiki claims they basically act as a faraday cage therefore it just prevents it from conducting in the first place.
 
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Soldato
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Will that not just prevent a component getting a static charge in the first place? I guess when I pick up the component I will get the static charge and ground it through the strap but I'm not sure though :confused:
 
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Will that not just prevent a component getting a static charge in the first place? I guess when I pick up the component I will get the static charge and ground it through the strap but I'm not sure though :confused:

yes. when you're fitting the component you'll be grounded. your pc is grounded through the psu during operation. A good surge protector/ups will also help to protect you from spikes whether your machine is on or not - but there are limits ;).

I know people who are happy building pcs or replacing components, and they just tap a nearby radiator to ground themselves and they never have a problem.
 
Soldato
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I understand about grounding myself before handling components. I've done Electronics where I had to handle very sensitive ICs, I can appreciate its importance. I'm solely concerned about components which may have been subjected to this static and if they're safe to put into working PCs. As I can't find anything on google about it I guess the static doesn't hang around and kill other components. I think if I hold each component and ground myself then any charge that is lingering will be drawn to ground. I'd just like some opinions from people who are educated/have experience with this.

I will be ordering an anti-static band though ;)
 
Soldato
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I know people who are happy building pcs or replacing components, and they just tap a nearby radiator to ground themselves and they never have a problem.

hhehehe i do that... i never knew anyone else did it

keep your optical drives if they are Sata, bin the IDE's...

if you hold a component with 1 hand and touch radiator or something grounded with your other all static = gone, thats assuming 2minutes earlier youve used a machine that generates static electricity to charge it :D...

it just wont work, no damage will be done to the other components... and even if static was present, youd have to touch the small metals on the PCB with it
 
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Soldato
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If your putting ram into a machine just touch the machine with one hand then pick up the ram, do that with the power cable in the back of the PC but the power turned off and you'll have been earthed and have no worry of static :)

....i think ive got that right lol
 
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I know people who are happy building pcs or replacing components, and they just tap a nearby radiator to ground themselves and they never have a problem.

That'll easily do, unless you've been rubbing a balloon against you're head or or are dressed entirely in nylon then the static risk is overblown.

My policy is avoid touching the chips as much as possible and keep it in an anti-static bag until it gets installed. I've yet to fry anything and I'm working with kit which has a price tag to match 4 or 5 PCs
 
Soldato
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I would appreciate more replies which back up the bit I quoted from platinum. Again I understand how to handle components so that isn't needed. I came home to find my PC wouldn't POST after a huge storm; I had no part in it :p
 
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If your putting ram into a machine just touch the machine with one hand then pick up the ram, do that with the power cable in the back of the PC but the power turned off and you'll have been earthed and have no worry of static :)

....i think ive got that right lol

With the power cable plugged in to the wall there is voltage on some of the PSU outputs. Don't do it. Find another earth like that radiator.

When I had anti-static training many years ago I was told that static discharges as low as 20 volts can damage components. Not immediately, but enough to shorten their life.
 
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In the last storm we had, I dutifully went around and unplugged all my computers, great I thought. Till the next day when my router was lit up like piccadilly circus.

Fried:
1x Netgear ADSL router
1x LAN/Network port

Whoops, don't forget the phone line peeps.

With the power cable plugged in to the wall there is voltage on some of the PSU outputs
If you turn the PSU off at the back then the mobo doesn't get power, you should always make sure this is so, when using it as a ground.
 
Soldato
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If you turn the PSU off at the back then the mobo doesn't get power, you should always make sure this is so, when using it as a ground.

Aye thats what i meant by turning the power off, i also press the power button a few times in an attempt to discharge anything in there (does that actually work)
 
Soldato
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Is physics education at that bad level?


y guess is that the charge that has been built-up will eventually degrade and cause no damage.
Yes, but a static charge dissipates quickly
Pretty much wrong both.
Static electricity is typically created when different non (/badly) conducting materials rub each others which causes transfer of electrons from one to another and leads to equal but opposite electric charges being stored in them. If air is dry and pure (humidity and impurities lower resistance) charge can continue building up and be stored for quite long time unless otherwise neutralized.
If either of these now charged objects touches, or comes close enough to exceed air's strike through voltage (~3kV/mm for dry air), any conductive object in different potential there happens electrostatic discharge (ESD) which either balances potential between source and target or completely neutralizes electric charge if target object is grounded.

With very strong electric charge already electrostatic field of charged object can cause damage to non grounded sensitive electronics by creating potential differences in it.


Will that not just prevent a component getting a static charge in the first place? I guess when I pick up the component I will get the static charge and ground it through the strap but I'm not sure though :confused:
In this situation (and always with computer parts) the problem isn't the component but you.
In dry environment human body (and clothes) can fast collect big electrostatic charge if surfaces are non conductive.
After that touching any conductive object causes sudden electrostatic discharge and nothing can protect sensitive electronics when it's left in route of this discharge.

Antistatic strap connected to ground prevents build up of this dangerous electrostatic charge and keeps you in neutral potential. (straps serial resistor also neutralizes charged objects you touch without sudden discharge)
Also when putting components into case it's better to first touch metal structure of case with skin in some part of your body so that possible charge/potential difference is balanced/neutralized trough you instead of by ESD trough component being installed. Keeping case grounded can prevent this problem but still exposes components to ESD unless you're yourself grounded similarly. (keyword is same neutral potential)

Antistatic bag protects components inside it because Faraday cage keeps electric charges outside of it.


Here's some experiments
http://www.sciencemadesimple.com/static.html

Also if you have electrically insulating floor or carpet on it (shoes work also) and for example wooden varnished table you can easily generate nice amounts of static electricity. (and below -10C weather is good, then air is much drier than in Sahara)
When all is clear and there aren't flammable fumes around just take one paper sheet from printer and start rubbing it against table's surface with your hand and after few minutes (the more the better) touch some electrically conductive object, also because like charges repel each others corners of object have highest charge levels so finger tip is best...
But don't come to complain if it hurts! ;)



There's no burn marks on any components so the only thing that comes to mind is static (lighting is basically a form of static electricity isn't it?)
Charge which is discharged in lightnings bolts is probably created by process similar to static electricity but scale is entirely different, both voltage and electric charge.

Current of lightning is measured pretty much in tens of kiloamperes. Strength depends much on climate of area because stronger thunderstorms naturally generate stronger electric charges but bolts up to 50kA should be possible pretty much in all areas. Total energy in lightning discharge is measured in millions of Joules and direct hit of stronger multiple strike can vaporize water exploding tree, split stones and instantly vaporize metal from utility lines and electric wiring of your house.
Also rapid pulse of very high current creates equally fast changing magnetic field which will induce current/voltage to every conducting object (including electric and phone cables) close to it.
 
Man of Honour
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Also rapid pulse of very high current creates equally fast changing magnetic field which will induce current/voltage to every conducting object (including electric and phone cables) close to it.

Should we therefore move our unplugged computers and whatnot to the middle of the room then while a storm is on?
 
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Static is a build up of charge. In the normal course of events charges like to equalize in much the same way water "finds its level".

When charges equalize - effectively you get a flow of charge - a current. The difference between the charges is the potential which drives the current.

So the issue with static is making sure that the any components and chassis and you are at the same potential relative to each other.

This is not necessarily earth pothential. If you use a wrist strap connecting you to a work sheet on your table upon which sits all your stuff you will not be working at earth potential - you will be at some floating potential. This doesn't matter.

I'm not quite sure what the OP is driving at. If a component has had a high charge on it due to static it is not necessarily damaged. It is only damaged if an earthed person has touched a delicate bit of the component and the thing has discharged through that delicate bit and done damage.

Re-using may not be a problem - it will probably work initially due to modern chip design built in redundancy. It is more likey to fail early early though since built in redundancy IS used up.

I think thats right :)
 
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