Description

This Standard specifies general safety requirements for approval and test purposes for isolating transformers for general use.

This Standard is an adoption with national modifications and contains the full text of IEC 61558-2-4:1997.

Scope

This part 2 of AS/NZS 61558 applies to stationary or portable, single-phase or polyphase, air-cooled isolating transformers, associated or otherwise, having a rated supply voltage not exceeding 1000 V a.c. and rated frequency not exceeding 500 Hz, the rated output not exceeding:

• 25 kVA for single-phase transformers;
• 40 kVA for polyphase transformers.

This standard is also applicable to isolating transformers without limitation of the rated output, however such transformers are considered as special transformers and are subjected to an agreement between the purchaser and the supplier.

The no-load output voltage or the rated output voltage does not exceed 500 V a.c. or 708 V ripple-free d.c.

The no-load output voltage and/or the rated output voltage shall exceed 50 V a.c. and/or 120 V ripple-free d.c.

This standard is also applicable to transformers associated with specific items of equipment, to the extent decided upon by the relevant IEC technical committees.

This standard is applicable to dry type transformers. The windings may be encapsulated or non-encapsulated