EFFECTS OF LIGHTNING This does not happen to others! Accident created by lightning is pretty common. Statistically, the percentage of damages caused by lightning on computing equipment is far from being unimportant Consequences from a disturbance are not always visible or immediate. The weakening of a component by a surge can entail a reduction of the life cycle of the equipment, or a 'deferred' breakdown. The user can not make from then on the link between the breakdown and the real cause. He will hurry to establish a bad diagnosis, thus an wrong treatment to solve the problem. Consequences of lightning on the installations are very real since the standardization of the electric installations makes henceforth compulsory, in some cases, the installation of surge protectors. Overvoltages have many types of effects on electronic equipment; in order of decreasing importance: Destruction Voltage breakdown of semiconductor junctions Destruction of bonding of components Destruction of tracks of PCBs or contacts Destruction of triacs/thyristors by dV/dt. Interference with operation Random operation of latches, thyristors, and triacs Erasure of memory Program errors or crashes Data and transmission errors Premature ageing Components exposed to overvoltages have a shorter life.