ESD - Avoiding damage
The object of this article is to increase your awareness of electro static potential when working on computers, and provide you with a means to help defeat it or at least suppress it.
OVERVIEW of Electro Static Discharge (ESD)
ESD is one of the top killers of computers. If precautions aren’t taken to ensure any static electricity is neutralized, damage can occur to sensitive components inside your system. This includes RAM “sticks”, the CPU (Central Processing Unit), hard disks, and “chips” on the motherboard which contain the chipset information for your motherboard. Also the “on-board” sound and video chips, cache memory chips, as well as electronics contained on add-in cards, etc.
When two objects which are at different electrical potentials come into direct contact with each other, electro-static discharge usually occurs. It’s not only the static sparks which you can see that can cause damage. A high electrostatic field on an object within close proximity of sensitive components can do damage.
You may think you are safe because you touched the frame of a system, and in many or even most cases you are, in that instance, and in that environment. However, introduce a dry atmosphere into the equation (heating season in cold climates) and the static potential dramatically increases. Damage may not be readily apparent, it can build up over time and cause a device to fail.
DO’s and DON’T’s
Most computer stores sell ESD grounding wrist straps. If you do much work inside systems, or you do a lot of tinkering with your own system, you should have one. The first time you avoid a “zap” because you’ve used it, it has easily paid for itself. In a pinch, you can construct one with a metal “alligator” (spring) clip, wire, and a 1 (One) MegOhm resistor. The resistor allows slow controlled bleed off to ground of charges which may occur.
Another (more expensive) item you may wish to obtain is an anti-static mat on which you place the system and components. These are usually made of conductive rubber, and provide a means (a snap for instance) of attaching a grounding lead and a wrist strap. This places you, the system, and anything on the mat at the same electrical potential.
Try to have your working environment around 40% to 50% relative humidity.
Avoid working in a carpeted area if at all possible.
Don’t touch the circuit board on the bottom of hard disks.
Don’t touch the contacts on memory or add-on peripheral cards. (Video, LAN, modem, sound, etc)
If you’re removing such things as memory or add-on cards from your system, place them on a conductive surface such as aluminum foil if you don’t have an ESD mat.
Avoid using a vacuum cleaner to remove dust etc from your system and components.
The movement of the air itself, and plastic nozzles can build very high static charges. A can of compressed air and a 1/2″ or 3/4″ wide natural bristle paint brush can be used to dislodge dust from air vents and the fins of heatsinks. Do not use a nylon or man made bristle brush. This method can be messy without an air hood/chamber to catch the dust but is much safer.
Keep all panels etc on your machines enclosure. This helps shield components, as well as reduce dust buildup, and helps with proper air flow from your cooling fans.
