Measurement of the total loss of cold-rolled nonoriented 3% silicon iron using an Epstein square

Cold-rolled nonoriented magnetic sheet steel has better magnetic properties when magnetised along the rolling direction than when magnetised across it. For example, losses along the rolling direction are 15¿20% below the mean. Owing to this difference in properties, values of core loss obtained when testing in an Epstein square may differ by as much as 4.5% according to the arrangement in the limbs of pieces cut along and pieces cut across the rolling direction. These differences have been investigated, and some of them have been explained on the basis of nonuniform flux and flux-waveform distortion. The best arrangement of the sample for testing is shown to correspond with that recommended in BS 601: Part 1: 1959.