This part of IEC 61287 defines terminology, service conditions, general characteristics and test methods of electronic power converters onboard of rolling stock. This International Standard is applicable to power electronic converters mounted on board railway rolling-stock and intended for supplying – traction circuits; – auxiliary circuits of power vehicles, coaches and trailers. The application of this standard extends as far as possible to all other traction vehicles, including trolley-buses, for example. This standard covers the complete converter assembly together with its mounting arrangements containing – semiconductor device assemblies; – integrated cooling systems; – integrated components like inductors, capacitors, transformers, resistors, contactors, switches; – semiconductor drive units (SDU) and related sensors; – incorporated protection circuits. The following types of power sources are taken into consideration: – AC contact lines, – DC contact lines, – on-board supplies such as generators, batteries and other electric power sources. This standard excludes converters which provide the electronic control supply for semiconductor drive units (SDU) and other supplies relevant to the converter operation such as sensors. NOTE 1 Electronic control equipment of converters and those sensors not related to semiconductor drive units and the printed circuit board assemblies of semiconductor drive units (SDU) are covered by IEC 60571. NOTE 2 Combined tests with the whole traction system or auxiliary supply system are not within the scope of this standard. E.g. rules for combined tests of a motor fed by a converter are given in the IEC 61377 series.