scope:

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: Single-phase transformers rated at less than 1 kVA and polyphase transformers rated at less than 5 kVA; instrument transformers; transformers for static convertors; starting transformers; testing transformers; traction transformers mounted on rolling stock; welding transformers and small power transformers.