This Standard covers the following independent or associated stationary or portable types of dry-type transformers, power supply units, including switch mode power supply units, reactors and combinations thereof in the field of safety. The windings can be encapsulated or non-encapsulated. They are not forming a part of the distribution network. This Standard will supersede AS/NZS 61558.1:2008 when the titles and contents of the parts 2 in the AS/NZS 61558 series have been updated to be used with AS/NZS 61558.1:2018. During this period AS/NZS 1558.1:2008 will also remain current. Regulatory authorities that reference this Standard in regulation may apply these requirements at a different time. Users of this Standard should consult with these authorities to confirm their requirements.