Epstein frame

An Epstein frame or Epstein square is a standardised measurement device for measuring the magnetic properties of soft magnetic materials, especially used for testing of electrical steels.

The International Standard for the measurement configuration and conditions are defined by the standard IEC 60404-2:2008 Magnetic materials - Part 2: Methods of measurement of the magnetic properties of electrical steel sheet and strip by means of an Epstein frame published by International Electrotechnical Commission.