Applies to grain oriented and non-oriented electrical sheet and strip for a.c. measurements of magnetic properities at frequencies up to 400 Hz and for d.c. magnetic measurements. Defines the general principles and the technical details of the measurement of the magnetic properties of electrical steel sheet and strip by means of an Epstein frame. The a.c. magnetic characteristics are determined for sinusoidal induced voltages, for specified peak values of magnetic polarization and for a specified frequency. This consolidated version consists of the third edition (2000) and its amendment 1 (2008). Therefore, no need to order amendment in addition to this publication.