IEC 60401-1:2020

Overview - IEC 60401-1:2020 (soft ferrite cores nomenclature)

IEC 60401-1:2020 is an international standard that defines terms and a consistent nomenclature for physical irregularities and dimensional references of magnetically soft ferrite cores. It provides a uniform vocabulary and graphical examples for common surface, bulk and shape irregularities (chips, pores, cracks, laminations, etc.), plus a method for designating the principal dimensional characters of ferrite core shapes. The edition replaces earlier IEC 60401-1 (2002) and IEC 60401-2 (2009) material and includes technical changes such as adding the terms “pores” and “scratch”, replacing “stratification” with “lamination”, and relocating clause content into Annex A.

Key topics and requirements

• Terminology for physical irregularities: standardized names and illustrated examples for surface, interior and shape defects (chips, protrusions, cracks, colour irregularities, machining-related marks, warping, non-flatness, non-circularity, etc.).
• Reference of dimensions: a consistent scheme for describing core dimensions on drawings, tables and catalogue sheets so manufacturers and users share the same dimensional characters.
• Location qualifiers: Annex A provides recommendations for combining general location names with more detailed qualifiers to specify exact irregularity positions.
• Designation method: rules for defining nomenclature of major physical attributes of ferrite core shapes (ring, E-core, ETD, PQ, pot, etc.), illustrated with core shape drawings and dimension tables.
• Graphical aids: many figures showing visual examples of irregularities and shape designations to reduce ambiguity in inspection and documentation.

Practical applications

• Creating clear, unambiguous technical drawings, specification sheets and product catalogues for ferrite cores.
• Writing inspection procedures and acceptance criteria for quality control of ferrite cores (visual inspection, dimensional checks).
• Improving supplier–buyer communication by using a common vocabulary for defects and dimensions.
• Supporting design and procurement of magnetic components used in power transformers, inductors, EMI filters and sensors where ferrite core geometry and surface integrity affect performance.

Who uses this standard

• Ferrite core manufacturers and mill operators
• Component design engineers and magnetic component specifiers
• Quality and inspection engineers
• Technical authors who prepare datasheets, drawings and acceptance criteria
• Purchasing and compliance teams working with magnetic materials

Related standards and resources

• IEC 60401 series and publications by IEC TC 51 (Magnetic components, ferrite and magnetic powder materials)
• Electropedia and IEC webstore for the latest editions and related normative references

Keywords: IEC 60401-1, soft ferrite cores, ferrite core irregularities, nomenclature, dimensional reference, magnetic cores, IEC standard.