The proper functioning of a computer system depends not only on its hardware and software but also on its external operating environment, primarily external and internal overvoltages. Recent statistics show that electronic information equipment frequently malfunctions due to component breakdown or burnout. A significant reason for this is the low tolerance of these components to transient overvoltages. If transient overvoltages are induced on the power and signal lines of the equipment, and the lines lack necessary transient overvoltage protectors, the electronic components will be damaged. Preventing external and internal overvoltages is part of the investment required for the normal operation of a computer system. Neglecting this investment can lead to system damage and the associated costs of replacement and repair. Over a certain period, the cyclical investment costs may exceed the initial cost of equipping the system with overvoltage protection devices. We will temporarily disregard political, social, and other influencing factors, which could potentially far outweigh the investment in surge protection devices.

The concept of overvoltage: Overvoltage refers to the operating voltage exceeding the normal supply value caused by external factors (mainly lightning) and internal workings of the power system. Transient overvoltages exist for a very short time, only tens of microseconds, but their damage is significant. Observations have shown that when the ground is struck by lightning, the energy of negative charge discharge averages 30kA; lightning strikes involving positive charge discharge to the ground are particularly intense, generally reaching 100kA, and sometimes as high as 200-300kA.