IEC 60404-8-7:2008 defines the grades of cold-rolled grain-oriented electrical steel strip and sheet in nominal thicknesses of 0,23 mm, 0,27 mm, 0,30 mm and 0,35 mm. In particular, it gives general requirements, magnetic properties, geometric characteristics, tolerances and technological characteristics, as well as inspection procedures. This standard applies to Goss textured grain-oriented electrical steel strip and sheet supplied in the final annealed condition in sheets or coils, and intended for the construction of magnetic circuits. The grades are grouped into two classes:
- conventional grades;
- high permeability grades.
They correspond to Class C.22 of IEC 60404-1. This third edition cancels and replaces the second edition published in 1998 of which it constitutes a technical revision. This revision extends the range of electrical steels to include the improved grades.