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What is Electrostatic Discharge (ESD)

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What is Electrostatic Discharge (ESD)

What is Electrostatic Discharge (ESD)
Static electricity is what makes your hair stand on end when you rub a balloon against your head. Of course, this assumes that you have hair--and that you'd have occasion to rub a balloon against your head. Static electricity also occurs when you walk across a carpet. Static electricity is not by itself a problem; the danger is in the discharge of the static electricity. You know, when you reach for the doorknob and zap! A blue spark as big as a towrope jumps from your finger to the metal. Although this may seem harmless (other than the pain), the potential for a lot of damage to a PC exists in that seemingly harmless spark. Remember that lightning is ESD in its most dreaded form.

Just because you can't feel an electrostatic discharge doesn't mean that it can't do harm to an electronic component. A human feels ESD at around 3,000 volts, but a mere 30 volts will do damage to electronic components. ESD is a far greater threat to the PC than anything else the PC service technician might do accidentally.

Most PCs are designed to have some ESD protection as long as their cases are intact and closed properly. Cases are chemically treated or have copper fittings designed to channel electrostatic discharge away from the sensitive components inside.

The danger from ESD damage begins when the case is opened and the fragile components on the motherboard are exposed. When a human with a static electrical charge touches anything inside the case, the charge can travel along the wires interconnecting the various electronic components. One of the wires may lead inside a component, and when the charge gets close enough to a metal part with an opposing charge, the internal wires and elements of components can explode or weld together.


  • An ESD shock of 30 volts can destroy a computer circuit.
  • An ESD shock you can feel, such as on a doorknob, has around 3,000 volts.
  • An ESD shock you can see carries about 20,000 volts.


The real problem with ESD damage is that not all of it is obvious. If an entire component is destroyed, you know it, and you replace the piece. When a component has been damaged but continues to work, though, days, weeks, or even months may pass before the component fails completely. More frustrating is intermittent partial failures that can't be isolated.


Eliminating Static Electricity


  • Always wear a grounded wrist strap that's connected to either a grounding mat or the PC chassis when you work on any part of the computer (except the monitor).
  • Treat carpeting inexpensively with antistatic chemicals to reduce static buildup. Aerosol cans of these chemicals are available in most computer or carpet stores.
  • Store all electrical components in antistatic bags when not in use.
  • Install a grounded pad under the PC. Before you touch the computer, touch the pad, and discharge any built-up static electricity.
  • If all else fails, install humidifiers to replace moisture in the air. Keep the humidity above 50 percent. Dry air can cause static electricity.


Last edited by FreeBooter on 28th February 2018, 9:49 pm; edited 1 time in total

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Neat info... Funny how our bodies can conduct electricity. It has never changed... always ground yourself before touching electronic parts! Smile...
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