This part of IEC 61000 specifies EMC immunity requirements which apply to electrical and electronic equipment intended for use in power stations and substations, as described below. Immunity requirements for electromagnetic phenomena with spectral contributions in the frequency range 0 Hz to 400 GHz are covered. No tests need to be performed at frequencies or for phenomena where no requirements are specified. This international standard sets immunity test requirements for equipment intended for use in the generation, transmission and distribution of electricity and related telecommunication systems. The electromagnetic environments encompassed by this standard are those which exist at locations " in power stations, and " in high and medium voltage substations. Installations to generate or convert into electrical power inside other industrial facilities are also covered by this standard as long as they, at their primary electrical connection, cannot be directly connected to the LV power network, e.g. where the generator output voltage is medium voltage or higher. NOTE 1 -In general, power stations comprise installations which are mainly built to convert some kind of primary energy into electrical energy. Moreover, these power stations are connected to the medium or high voltage power system directly or via a step-up transformer. Installations which are in addition to other primary functions (like photovoltaic cells or combined heat power systems in private houses and which are connected to the low voltage network) are not covered by this standard. The object of this standard is to define immunity test requirements for equipment defined in the scope in relation to continuous and transient, conducted and radiated disturbances, including electrostatic discharges. The immunity test requirements are given on a port-by-port basis, and selected according to the location, with differentiated levels for equipment to be installed in power stations or substations. In special cases, situations will arise where the level of electromagnetic disturbances may exceed the levels specified in this standard; in these instances, special mitigation measures shall be adopted. The immunity requirements are suitable for satisfying the particular needs related to the functions and tasks of equipment and systems, for which reliable operation is required under realistic electromagnetic conditions; in this respect, this standard establishes performance criteria for different functional requirements. This generic EMC immunity standard is applicable if no relevant dedicated product or product-family EMC immunity standard exists. According to IEC Guide 107, this generic standard shall be considered for the preparation or revision of any EMC standard referring to specific products used in power stations and substations. NOTE 2 -Product standards covering EMC aspects for equipment to be used in power stations or substations are for example IEC 62271-1 (Switchgear and controlgear) or IEC 60255-26 (Measuring relays and protection equipment). Non-electronic high voltage and power equipment (primary system) are excluded from the scope of this standard. Emission requirements are not within the scope of this standard and are covered by relevant product or product-family standards. NOTE 3 -Where no dedicated product or product family standard covering emission requirements exists, the generic standard IEC 61000-6-4 applies.