Shielding and magnetic field reduction for small and medium size transformers and reactors

摘要

Data on fields from medium power distribution transformers in the range of 70 to 90 kVA are presented for information. A review of magnetic field practice and related shield effectiveness for small transformers (down to 100 watts) is shown and contrasted to problems with large transformers. Suggestions for formal measurements and review by national test groups are presented.