Until the introduction of solid state devices, most AC-powered equipment was too insensitive to be upset by "dirty" or surging power. However, electrical power surges and the damage they can cause are commonplace today. Our home and workplace are comprised of solid state devices vulnerable to surges. We deal daily with computers, office machines, data, telecommunication equipment, major appliances, etc. All of these depend on solid state devices which are vulnerable to surge.
Solid state devices depend on consistent,, good-quality power. A single powerful surge literally melts, welds, pits, and burns its way through solid state circuits and components.
Device failure is often the result of many small surges and the cause is often not detected by the repairing technician. In addition to the loss of use, priceless stored data can be lost and meaningful input or output information is turned into nonsense.

The driving force to shrink device geometries to increase speed and storage capacity will continue to make solid state devices even more sensitive to dirty power and surges.
Many people think of surge damage as being caused by a single, catastrophic event such as a lightening strike. While lightning is one of the most powerful and destructive surges, it's not always the cause of most of the surge damage. In reality, surges range from mighty to the minuscule.
Smaller surges occur several times a day, or hundreds of times an hour. Almost continuous surges can be produced by sources ranging from 250 to over 1,000 volts. Typically, they are caused by the operation of electric motors or other inductive loads such as elevators, office machines, switcher equipment. Microwave ovens, vacuum cleaners, lame dimmers and countertop appliances are some of the surge sources in the home.
Powerful, random surges result from the switching of an inductive load such as an electric motor starter, arc welder, furnace ignition, compressor, etc. and these momentary surge sources range from 250 to over 3, 000 volts.