This part 2 of IEC 61558 applies to associated power transformers for switch mode power supplies, single-phase or polyphase, air-cooled: separating transformers; isolating transformers; safety isolating transformers, 10 kVA for single-phase transformers; 16 kVA for polyphase transformers. This standard is applicable to dry type transformers. The windings may be encapsulated or non-encapsulated. It has the status of a group safety publication in accordance with IEC Guide 104 This part 2 supplements or modifies the corresponding clauses in IEC 61558-1