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I just take off my shoes, tap a doorknob, make sure I'm not working on a carpet and hold the case. I haven't zapped anything yet.

volts mean nothing?? Im very suprised to hear a so called EE say something like this. You are correct that the current is what is dangerous. But to say volts mean nothing is just not true, and its irrisponsible. And, that wasnt my point. The point was that 99% of the readers do not have a clue how much potential you can generate by dragging your feet. Furthermore my statement was valid. Your body will hold enough current to blow a CPU. Obviously the voltage is there.

This is to be debated??? There is no debating, touching a case that does not have ITS power supply plugged in will only bring you and the system to zero potential. Thats a fact. Its not debatable. Its fact. And if your worried about power surges blowing things then you better go unplug EVERYTHING in your house. That thing on the back of the power supply that has a | and a 0 on it, thats the power supplies power switch. When its off, no power surge short of a lightening strike is going to jump it and damage anything, because that is a physical switch, not a solid state device that can be blown. And even when that switch is off, your case is still earth grounded.

Put it this way, some people have no choice but to work on carpet. So if they are only holding the case, not plugged to the wall, and they start to shuffel thier legs back and fourth as they change positions, they can potentially charge themselves and the case. Now when they reach over and pull a new CPU or vid card or some other component out of the static bag, without ever having a clue that anything happened they can discharge into the component and kill it. At best it can be taken to within an inch of its life and it will only last a few months before dying completely. This is a fact that any SEASONED engineer or technician knows all too well. And the only way to bleed off the charge is by having yourself or the case your touching actually grounded. And this usually means a plug to that wall.

WERD!

If you can work in your garage with a cement floor. All you have to do is remove your shoes. The concrete, poured directly onto the gournd for your foundation. also your concrete basement floor, works like a huge ESD mat. Most people dont know this. The drawback to concrete vs an esd mat or strap, you CAN get electrocuted with bare feet on concrete. its true

If you were to have a power serge when working on your pc, just because you have the switch flipped wont protect you. Peoples computers have fried after a power surge and their computer was plugged into a serge protector and the switch was off. If it is strong enough to pass the serge protector (it fuses it closed, thus letting the current pass), the power supple wont stand a chance either. You don't have ot be hit by lightning for this to happen. If a transformer near by blows, it can do the damage.

I work on carpet and I hate to break it to you but you can ground yourself by touching your case from time to time. How are cars grounded? How are aircrafts grounded during flight? Cars are touching the ground, but the rubber insulates it so electricity wont go to the ground. Being grounded dose not mean touching the earth. It is relevance to 0, or low current/voltage. Air crafts are grounded during flight as well. How, by discharging the electricity into the air. If you were to get hit by lightning during flight, you wont crash. The plane is designed to disperse the electricity into the air.

Thus, by touching your case you discharge and built up charge in you and into the metal. Example, ever touch a door knob and get zapped? The house didn't catch fire did it? Most doors are wood which are terrible conductors. But you still discharge yourself and are now into an equilibrium to the relevance of ground.

Another thing about the carpet, you do know that it is suggested to not work in any rooms that have very low humidity right? This is because humidity acts as an insulator and makes it much harder to shock things. Example, in summer when you get out of your car, do you shock yourself? Now in winter when you get out of your car, do you shock yourself? Hell I shock myself in winter getting out of a Saturn. They are made out of plastic for god sake!

As for the concert floors, that is interesting. I did not know that.

Me again
I can relate to KylesSTL - Once working on a color TV in a preachers house, my little pinky got too close to the Horizonal oscillator (a couple of KV's at 15 KHz) - set my on the floor. All I could say was o that hurt. Also got hit with the 35 KV Picture tube voltage. That was before I heard about wrist staps, And da__ glad I was not waring one!

This is when I do not recommend wearing a strap - Working on Powered on systems with voltages that can be harmful to you.

For you who like morbid stories - What happens when you are electricuted is you start out with a high resistance, but as the current passes thriugh your body the current generates heat which causes your cells to expand and rupture reducing your resistance which increases the current which intern ruptures more cell - Your resistance
goes even lower untill your a DEAD SHORT.

As someone pointed out it not the voltage that kills, its the current, What he forgot was it takes that Voltage POTENTIAL to generate the current. No one has ever been harmed for a 12 Volt - 200 Amp source, But a 110 Volt 100 milliamp source can kill if contact exceeds several minutes ( Don't know the exact time )

OK then lets take this one at a time:

You are correct, a power surge on the NEGATIVE terminal can damage lots of things, regardless of switch orientation. Your arguement, though true, makes no sense to me in the sense that a power surge can happen any time. And, its far more likely to happen while your "using" your computer, as opposed to "working in" your computer, so that is in no way a valid arguement to simply UNPLUG your case, eliminating the earth ground, while working in it. Try carrying your case (empty so as not to be stupid) around and dragging your feet on the carpet on a dry winter day and touch the doorknob. you still make a spark. You are NOT grounded simply by touching your case. Period. you are simply at zero potential to the case. R.C. back me up here.

I hate to break it to YOU, but you are NOT grounded simply by touching your case. Period. You are simply at zero potential. Again, carry your case around while you drag your feet on carpet and touch the doorknob, or your boyfriend. You get a spark cause your not grounded. Airplanes are in fact susceptable to lightening strikes. What they use are called static wicks to bleed off electricity, not just into the air, but by oppositely charged polarizing ions carried in the moisture in the air. They also have backup systems that physically isolated, and are only used in case the primaries fail.

The corner panels are plastic. The frame, some trims, and lots of other things are metal and you are simply discharging to the batteries negative terminal. A car is "grounded" only in the sence that its negative terminal is at a zero voltage "only in reference to its positive terminal" If a car, not running, just with the stereo on, has its negative terminal removed, the stereo goes dead. Now if the car were truely grounded, earth ground, and the neg terminal removed, the stereo would continue to run as the DC current would simply run into the GROUND.

The same way plastick ESD chairs have a brass chain dragging on the ground. The plastic wheels are insulators. When you slide off the fabric of the seat you create a charge that has to be blead off. Thats the reason for the chain.

Are you guys still harping on this?

This thread is absolutely hilarious but about as useful as tits on a warthog.

The fact is, new builders should wear an anti-static strap and from what I’ve read so far, “experienced” builders should as well. Newegg would no doubt receive fewer “DOA” components as a result.

In a perfect setting, static can be eliminated at a specific time but a host of unexpected changes could occur in an instant.

Just buy a $6.00 band. It’s six foot long!!! The only problem it could possibly present is knocking over your beer bottle.

Yea I just love when someone who is obviously NOT an electrical engineer and DOESNT fully understand electrical thoery tries to wrongly explain things.

Little_Scrapper. Yes, You are correct, and a good explaination, in your response to SPaztic7.

The terminology of "Ground" is often blurred. In the case of Auto's, and Airplanes. the chassie is is refered to as ground and the return leg is often tied to chassie ( Return can refer to the negative (Positive voltage, OR the Positive can be tied to "Ground" - some Very old cars had a Positive Ground. In this case ground is a relative term..

The car is not an Earth Ground - When a high voltage line falls on a car you are not fryed, until you step out and put one leg on the Earth.

As little_scrapper pointed out an aircraft frame is designed to bleed off a charge. But when on the ground, and parked the have a "Ground" stap inplace!

In small electronic systems, unless a ground is connected the Chassie is relaly nothing more than a EMI shield.

Please note, Touching "Painted" case is not an exceptable ground.