AS/NZS 61558.2.16:2010 deals with the safety of switch mode power supply units and transformers for switch mode power supply units. Transformers incorporating electronic circuits are also covered by this standard. This Standard will supersede AS/NZS 61558.2.17:2001 three years from the date of publication (i.e. on 31 May 2013). During this period it is anticipated that regulatory authorities will approve transformers for switch mode power supplies to either standard.