Surge protection is the process of protecting electronic systems or equipment from voltages and currents which are outside their safe operating limits. These surge voltages and currents can be generated by short circuits, lightning or faults from a power system and usually enter the electronic system along inter-equipment wiring. The surges may be galvanically coupled into the system as in the case of a direct lightning strike, through an inadvertent connection of the power system to the wiring, or as a result of an earth potential rise. They may be capacitively coupled into the system which may occur when a data system is used in the vicinity of a high voltage power line. They may be inductively coupled into the system as may occur if the wiring is run in parallel with large currents running in a power circuit feeding a high power motor.