This document supersedes EN 61439-1:2009. EN 61439-1:2011 includes the following significant technical changes with respect to EN 61439-1:2009: — revision of service conditions in Clause 7; — numerous changes regarding verification methods in Clause 10; — modification of routine verification in respect of clearances and creepage distances (see 11.3); — adaption of the tables in Annex C and Annex D to the revised requirements and verification methods; — shifting of tables from Annex H to new Annex N; — new Annex O with guidance on temperature rise verification; — new Annex P with a verification method for short-circuit withstand strength (integration of the content of IEC/TR 61117); — update of normative references; — general editorial review.