scope:

This European Standard applies to emission and immunity aspectsof EMC for electrical and electronic apparatus intended for use onrailway rolling stock. EN 50121-3-2 applies for the integration ofapparatus on rolling stock. The frequency range considered is fromDC to 400 GHz. No measurements need to be performed at frequencieswhere no requirement is specified. The application of tests shalldepend on the particular apparatus, its configuration, its ports,its technology and its operating conditions. This standard takesinto account the internal environment of the railway rolling stockand the external environment of the railway, and interference tothe apparatus from equipment such as hand-held radio- transmitters.If a port is intended to transmit or receive for the purpose ofradio communication (intentional radiators, e. g. transpondersystems), then the radiated emission requirement in this standardis not intended to be applicable to the intentional transmissionfrom a radio-transmitter as defined by the ITU. Immunity limits donot apply in the exclusion bands as defined in the correspondingEMC related standard for radio equipment. This standard does notapply to transient emissions when starting or stopping theapparatus. The objective of this standard is to define limits andtest methods for electromagnetic emissions and immunity testrequirements in relation to conducted and radiated disturbances.These limits and tests represent essential electromagneticcompatibility requirements. Emission requirements have beenselected so as to ensure that disturbances generated by theapparatus operated normally on railway rolling stock do not exceeda level which could prevent other apparatus from operating asintended. The emission limits given in this standard takeprecedence over emission requirements for individual apparatus onboard the rolling stock given in other standards. Likewise, theimmunity requirements have been selected so as to ensure anadequate level of immunity for rolling stock apparatus. The levelsdo not however cover all cases which may occur with an extremelylow probability of occurrence in any location. Specificrequirements which deviate from this standard shall be specified.Test requirements are specified for each port considered. Thesespecific provisions are to be used in conjunction with the generalprovisions in EN 50121-1.