Covers general purpose and power transformers of the air-cooled, dry, ventilated, and nonventilated types rated no more than 500 kVA single-phase or no more than 1500 kVA three-phase or general purpose and power transformers of the exposed core, air-cooled, dry, and compound-filled types rated more than 10 kVA but no more than 333 kVA single-phase or no more than 1000 kVA three-phase to be used in accordance with the National Electrical Code, NFPA 70.