This part of IEC 63093 specifies the dimensions that are of importance for mechanical interchangeability for a preferred range of ring-cores@ also called toroid cores@ and the effective parameter values to be used in calculations involving them. It also gives guidelines on allowable limits of surface irregularities applicable to ring-cores. This document is a specification useful in the negotiations between ferrite core manufacturers and users about surface irregularities.
IEC 63093-12:2019 history
2019IEC 63093-12:2019 Ferrite cores - Guidelines on dimensions and the limits of surface irregularities - Part 12: Ring-cores