This part of IEC 60404 is applicable to Fe-based amorphous strips specified in IEC 60404-8-11 for the measurement of AC magnetic properties at frequencies up to 400 Hz. The object of this part is to define the general principles and the technical details of the measurement of the magnetic properties of Fe-based amorphous strips by means of a single sheet tester. The single sheet tester is applicable to test specimens obtained from Fe-based amorphous strips of any quality. The AC magnetic characteristics are determined for a sinusoidal induced voltage, for specified peak values of magnetic polarization and for a specified frequency. The measurements are made at an ambient temperature of (23 ± 5) °C on test specimens which have first been demagnetized. NOTE 1 The single sheet tester specified in this document is appropriate for other materials which have similar magnetic properties and physical characteristics as Fe-based amorphous strip, such as nano-crystalline soft magnetic strip. The single sheet tester for electrical steel sheets is specified in IEC 60404-3. NOTE 2 Throughout this document the term magnetic polarization is used as described in IEC 60050-121. In some standards of the 60404 series, the term magnetic flux density is used.