This standard applies to dry-type power transformers (including auto-transformers) having values of highest voltage for equipment up to and including 36 kV.
The following small and special dry-type transformers are not covered by this standard:
— single-phase transformers rated at less than 1 kVA and polyphase transformers rated at less than 5 kV A;
— instrument transformers (covered by IEC Publications 185: Current Transformers, and 186: Voltage Transformers);
— transformers for static convertors (covered by IE C Publications 84: Recommendations for Mercury-arc Convertors, 119: Recommendations for Polycrystalline Semiconductor Rectifier Stacks and Equipment, and 146: Semiconductor Convertors);
— starting transformers;
— testing transformers;
— traction transformers mounted on rolling stock;
— flameproof and mining transformers;
— welding transformers;
— voltage regulating transformers;
— small power transformers in which safety is a special consideration.
Where IEC standards do not exist for the transformers mentioned above or for other special transformers, this standard may be applicable as a whole or in parts.
With the publication of this standard, the requirements of IEC Publication 76 apply to dry-type transformers only in so far as they are referred to in this standard.
Where reference is made to specific clauses and sub-clauses of various parts of IEC Publication 76, it is to be understood that the editions are as follows:
76-1, 76-2, 76-4, 76-5: 1976. 76-3: 1980.