BS EN IEC 63093-1:2020 pdf download.Ferrite cores一Guidelines on dimensions and the limits of surface irregularities Part 1: General specification.
This part of IEC 63093 specifies the dimensions and allowable limits of surface irregularities of ferrite cores.
It is intended that this document includes ferrite cores which are widely used and referenced in industry, either because they are included in national standards, or because they are seen to have broad-based use in industry. Where applicable, it is intended that the existing industrial name for each standard part appears with the part within this series.
It is intended that this document excludes ferrite cores which are specialty cores with limited use. Also, special cores which are only marginal variations upon standard cores are excluded.
A ferrite core produced by only one or two suppliers can generally be considered a specialty part, and not suitable as a standard core within this series. A ferrite core produced by three or more competing manufacturers can generally be considered to be a candidate to be included in this series.
lEG publishes electrical standards for families of ferrite cores, as well as this series of dimensional standards for families of ferrite cores. Modifications to the ferrite cores listed in one type of standard are reflected in the other type.
This document is considered as a general specification useful in the dialogue between ferrite core suppliers and users about surface irregularities.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEG 60401-1, Terms and nomenclature for cores made of magnetically soft ferrites — Part 1: Terms used for physical irregularities
IEG 60401-2, Terms and nomenclature for cores made of magnetically soft ferrites — Part 2: Reference of dimensions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60401-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://wwW.electropedia.org/
• ISO Online browsing platform: available at http://wwwiso.org/obp
chips and ragged edges, p1.
areas with missing surface material as a result of mechanical impact during handling
3.2 crack
surface irregularity which has a width much smaller than its length, and penetrates into the core
3.3 flash
sharp feather-edge wall extending beyond the intended contour surface of the core
3.4 Pull-Out
removal of a surface layer of the core due to die “sticking”
3.5 pore
hole left on the surface of cores after sintering and surface finishing
3.6 crystallite
grain of abnormal size distinguishable on the surface, often with sparkling facets
4 Dimension descriptions
Dimension descriptions shall be as indicated in IEC 60401-2.
5 Location and functions of core parts and surfaces
5.1 General
Figure 1 shows the location of the main core parts and surfaces of an RM-core.
5.2 Mating surfaces
These surfaces are generally ground in order to limit the residual air gap between the two core halves. Consequently, Irregularities on these surfaces have to be considered as major ones, and carefully evaluated with regard to their influence on the magnetic properties of the complete circuit.
5.3 Centre post
This should be considered as the most important part of the core due to its function of carrying the total flux generated by the winding. The centre post of ferrite cores is generally circular (with or without a hole) or rectangular. If the centre post is circular, it is called centre pole and if the centre post is rectangular, it is called centre leg.
5.4 Outer legs
The main function of the outer legs is to guide the magnetic flux in a closed magnetic circuit.
5.5 Back, bottom surface and back surfaces
The back has the same magnetic function as the outer legs: it can include wire-slots and wire- way areas (for example on RM-cores). the shapes and dimensions of which are dictated by the winding and isolation requirements.
Besides accommodating clamping, the back surface (ground or not) serves as a reference plane for grinding the mating surface to achieve its required parallelism, flatness and smoothness.
5.6 Wire-slot area
The wire-slot area is the lateral area of the outer walls, interfacing with the cut-out portion.BS EN IEC 63093-1 pdf download.