IEC 63093-6:2018

Overview

IEC 63093-6:2018 is an International Electrotechnical Commission (IEC) standard that provides guidelines on dimensions and allowable surface irregularities for ETD ferrite cores used in power supplies. It defines the principal dimensions required for mechanical interchangeability of a preferred range of ETD-cores, the essential dimensions of compatible coil formers, and the effective parameter values used in magnetic calculations. The document also gives inspection and acceptance guidance for surface defects (chips, cracks, flash, pull-outs, crystallites, pores) and includes annexes on derived standards, gauge examples and allowable chip areas.

Key topics and requirements

• Dimensional requirements: Principal core dimensions and tolerances for standard ETD sizes (ETD 19 to ETD 59) are specified to ensure mechanical interchangeability. Table 1 and Figure 1 of the standard list these primary dimensions.
• Coil former dimensions and pin locations: Essential dimensions and tolerances for coil formers and pin layouts are included to ensure correct mounting on printed circuit boards and reliable assembly interfaces.
• Effective parameter values: Table 2 provides effective magnetic parameters and A-values required for calculations. Definitions and calculation methods reference IEC 60205.
• Limits of surface irregularities: Detailed guidance for acceptable levels of surface defects - including chips, ragged edges, cracks, flash, pull-outs, crystallites and pores - with illustrative figures and inspection area/length references.
• Gauging and inspection: Annex B offers example gauge dimensions and a recommended checking procedure; Annex C (informative) retains allowable chip-area data originally from IEC 60424‑3.
• Integration and provenance: This edition consolidates IEC 62317‑6:2015 and IEC 60424‑3:2015 into a single document and cross-references IEC 60401‑1 and IEC 60424‑1 for terminology and general rules.

Applications and practical value

• Ensures mechanical interchangeability between ferrite core suppliers and users, simplifying procurement and inventory management for ETD cores used in switch‑mode power supplies and transformers.
• Enables designers and engineers to accurately calculate magnetic parameters for inductors and transformers using standardized effective values.
• Provides acceptance criteria for quality inspectors and manufacturers during incoming inspection, production control and supplier negotiations.
• Supports PCB layout and mechanical design by standardizing coil former pin locations and mounting requirements.

Who should use this standard

• Ferrite core manufacturers and component suppliers
• Power-supply and magnetics designers (transformers, chokes, inductors)
• Procurement and quality assurance teams negotiating tolerances and acceptance criteria
• PCB designers and assembly engineers concerned with mounting and interchangeability

Related standards

• IEC 60205 (calculation of effective magnetic parameters)
• IEC 60401-1 (terms for ferrite core irregularities)
• IEC 60424-1 (general limits of surface irregularities)
• Previously related: IEC 62317-6:2015 and IEC 60424-3:2015 (now integrated)

Keywords: IEC 63093-6, ETD cores, ferrite cores dimensions, power supplies, surface irregularities limits, mechanical interchangeability, coil formers, effective parameter values.