AS/NZS 61558.2.4:2009 pdf free.Safety of power transformers, power supplies, reactors and similar products for supply voltages up to 1 100 V – Part2.4:Particular requirements and tests for isolating transformers and power supply units incorporating transformers.
This part of IEC 61558 deals with the safety of isolating transformers for general applications and power supply units incorporating isolating transformers for general applications. Transformers incorporating electronic circuits are also covered by this standard.
NOTE 1 Safety includes electrical, thermal and mechanical aspects.
Unless otherwise specified, from here onward, the term transformer covers isolating transformers for general applications and power supply units incorporating isolating transformers for general applications.
NOTE 2 For power supply units (linear) this part is applicable. For switch mode power supply units, IEC 61558-2-16 is applicable together with this part.
This part is applicable to stationary or portable, single-phase or polyphase, air-cooled (natural or forced) independent or associated dry- type transformers. The windings may be encapsulated or non-encapsulated.
The rated supply voltage does not exceed 1100 V a.c., and the rated supply frequency and the internal operating frequencies do not exceed 500 Hz.
The rated output does not exceed:
— 25 kVA for single-phase transformers;
— 40 kVA for polyphase transformers.
This part is applicable to transformers without limitation of the rated output subject to an agreement between the purchaser and the manufacturer.
NOTE 3 Transformers intended to supply distribution networks are not included in the scope.
The no-load output voltage or the rated output voltage does exceed 50 V a.c. or 120 V ripple-free d.c., and where applicable, does not exceed 500 V a.c. or 708 V ripple-free d.c.
The no-load output voltage and the rated output voltage may be up to 1 000 V a.c. or 1 415 V ripple-free d.c. for special applications.
This part is not applicable to external circuits and their components intended to be connected to the input terminals and output terminals of the transformers.
Transformers covered by this part are used in applications where double or reinforced insulation between circuits is required by the installation rules or by the end product standard.