IEC 62041:2010 applies to transformers, reactors, power supply units and combinations thereof covered by the IEC 61558 series of standards. This standard deals with the electromagnetic compatibility requirements for emission and immunity within the frequency range 0 Hz - 400 GHz. No measurement needs to be performed at frequencies where no requirement is specified. This second edition cancels and replaces the first edition published in 2003. It constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - the frequency range for tests according to IEC 61000-4-3 has been extended above 1 GHz according to technologies used in this frequency area; - the testing requirements according to IEC 61000-4-11 have been amended significantly; - the inclusion of a clause on tests in series production; - the inclusion of a new clause on measurement uncertainly, and - the inclusion of requirements on DC power ports and telecommunication ports.