I have a similar, but stranger, problem.

I have a cloth-covered recliner in my den, about 3 ft away from my PC case. About every third time I get up out of the recliner, the static I generate will reboot my PC. This occurs before I ever touch the case, the keyboard, the mouse, etc. It's as if the static leaps throgh the air itself to zap the PC.

So far, it hasn't harmed my computer, but it's just a matter of time. I'm very puzzled by this - the chair isn't "connected" in any way to the PC or the wooden desk - no wires, carpets, etc. The PC sits 'in' the desk, so it's not even touching the same floor.

Is this still a grounding issue?

Thanks,

Mike B

If you don't touch the PC and don't feel that discharge, how do you know it's a static issue? It could be that the chair creates a vibration that shakes a loose wire everytime you get up.

Although it is theoretically possible for a static differential to travel across static-prone materials (like your carpet) because the way static works by the transfer of electrons from one non-grounded surface to another. As you walk along your carpet or rustle the cloth cover of your chair, you collect free electrons from those surfaces building a negative charge on your body. The discharge of static is the sudden transfer of that differential into a non-grounded metallic or wet object with which there is a strong enough differential to facilitate the discharge, or to a grounded metallic object.

There has to be a charge differential, and it's usually between your body and those surfaces. It could, however, build between different areas of the same surface and discharge itself into your pc. However, I've never seen this happen.

How this would relate to your scenario in either case is that these charges will discharge very easily into any metal object (doorknob, metal desk, PC) and to a lesser degree, objects with a high water content (water itself, other people). If you were to build up this charge and touch a PC which is not properly grounded, the resulting discharge will flood the electronic components, crashing the PC and very possibly damaging the integrated circuits. However, a decent PSU also has a shut-down feature which is what is really turning off your PC when you shock it. This doesn't preclude, however, the danger of damage. In any case, if your PC is properly grounded, the charge will go through the metal of the case, into the PSU, and then into the ground wire to be discharge to earth. This doesn't mean that the PSU won't still shut down your PC when you shock it, but you won't damage the PC because the shock will not go into the components of the PC (electricity takes a route very close to the path of least resistance to ground).

If the problem you are having is static, it sounds to me like your PC is not properly grounded. I don't think you could send a charge differential across the room to such a degree that it would shut down a properly-grounded PC. Try plugging it into other outlets. However, the electrical system of your house is most likely grounded in one spot, and if the connection to that ground is broken, then every outlet will have the same problem. Also, try putting your computer onto an insulating material. I have a metal-framed desk with a glass desktop. My PC was touching the metal frame and rebooted every time I built up a charge and touched my desk. Moving it a few inches to that the PC was entirely on the glass fixed the issue. Also, wood is an excellent insulator. If your desk is entirely metal, then you should be able to get a rubber mat to place under your PC. Don't use household plastics, as they don't conduct electricity THROUGH the material, but can possibly conduct it along the surface. This doesn't apply to anything you might find in a store labeled as an anti-static mat.

John,
In reference to your DEC 18 Posting:
Anti Static mats and wraps ARE CONDUCTIVE, but need a proper path to GND in order to work Properly. If you are carrying a 200KV charge, but are wearing rubber soled shoes, then there is no path to the mat, or to the attached GND, so you will still discharge through the connected peripheral device or computer chassis. Having the chassis itself on a ESD (anti-static) mat still leaves the connected peripheral device exposed as the path to GND is still through the components attached to the MB vs. the chassis.

In the case of Anti-static wraps, there are emulsifiers (sp) that prevent the buildup of high levels of static by being conductive on a level that disperses them prior to thier being damaging. I recall a seminar I took back in the '80s on "Pink Poly" (a early ESD resistant packaging material that is still in use) in which it was shown that 3' of cellophane tape could carry upwards of 300KV upon being peeled from the roll, but the addition of the emulsifier reduced this to manageable levels.

In the case of both mats and wraps, the effectiveness does leech out over time and need to be replace periodicly, the time frames vary with the product.

All in all, eliminating or reducing the static producing capabilities in the general area of the computer is a very viable option, in which case spraying an emulsive agent such as dish soap in low concentrations is a good solution.

OMG First of all I WROTE 3 books about static electricity before I graduated college. I AM the world's foremost authority ON the issue.

EVERYTHING Patrick O'Furniture says is wrong. It's astounding... He's like a reverse barometer of what you need to do.

First off, spraying soapy water on your carpet will likely generate so MUCH static electricity that it will KILL you just by walking into your house and touching a doorknob. (Not to mention, make you more likely to slip and fall should you ever need to suddenly sprint for some unknown reason)

In my first paper, "Electrons, the positive side of negativity" I wrote about the dangers of soapy water in spray bottles. I can't believe you guys haven't read it because it's pretty much standard reading for any physics major now.

PLEASE, keep your mouth shut if you don't know you're talking about, you're embarrassing yourself and MOST likely KILLING people in the process.

dr electron said:

As the self proclaimed worlds foremost authority on anything, you have to recognize that Patrick wasn't totally wrong about everything.

Please list the books that are standard reading for anyone, much less ANY physics major, as most of physics has nothing to do with ESD.

Please indicate how spraying a mild solution of emulsifiers on a conductive surface constitutes a life threatening hazard.

Though it is recognized that the "atomization" or separation of a solution can generate static electricity, by the time the solution hits the conductive surface there is little or no residual electrical effect, as long as the path to ground is less resistive than is necessary for the proper discharge of the voltage build up, which is determined by a simple formula for Static or Direct Current electricity as expressed by the V=I*R formula that indicates that the resistance to ground becomes less given the higher voltage, thus reducing the life threatening AMPERAGE necessary to cause life threatening discharge.

I would love to know why you joined us here at HWA just to make this ambiguous and incorrect posting....but that's just me.

Pease support your asertations in a manner that is supportive of your self proclaimed "expert" status.

BTW: I dogpiled your mentioned seminal paper on "Electrons, the positive side of negativity" and though I came up with several pages of partial hits, nothing came up to support your assertations, at all. A link to your work would be apprecated.

If you can provide this information, I will be more than happy to audit your expressed expertese. If not, then take your own advice.
Thank you.

It's pronounced "thermometer."