This Recommendation applies to newly manufactured current transformers for use with electrical measuring instruments and electrical protective devices at frequencies from 15 to 100 Hz (c/s).
Although the requirements rel?te basically to transformers with separate windings they are also applicable, where appropriate, to auto-transformers.
SIS SEN 27 05 00-1974 history
1974SIS SEN 27 05 00-1974 Power capacitors International recommendations' validity as Swedish standard