IEC 60793-2-50 Commented version

IEC 60793-2-50:2025 CMV contains both the official standard and its commented version. The commented version provides you with a quick and easy way to compare all the changes between IEC 60793-2-50:2025 edition 7.0 and the previous IEC 60793-2-50:2018 edition 6.0. Furthermore, comments from IEC TC 86 experts are provided to explain the reasons of the most relevant changes, or to clarify any part of the content.

IEC 60793-2-50:2025 is applicable to optical fibre categories B-652, B-653, B-654, B-655, B‑656 and B-657. A map illustrating the connection of IEC designations to ITU-T designations is shown in Table 1. These fibres are used or can be incorporated in information transmission equipment and optical fibre cables. Three types of requirements apply to these fibres:
- general requirements, as defined in IEC 60793-2;
- specific requirements common to the class B single-mode fibres covered in this document and which are given in Clause 4;
- particular requirements applicable to individual fibre categories or specific applications, which are defined in Annex A to Annex F.
For some fibre categories (shown in the relevant family specifications), there are sub-categories that are distinguished on the basis of difference in transmission attribute specifications. The designations for these sub-categories are documented in the individual family specifications. Table 1 shows a map from the IEC designations to the ITU-T recommendations.
This seventh edition cancels and replaces the sixth edition published in 2018. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition.
a) The addition of a 200 µm coating nominal outer diameter option for B-654A, B, C fibres in Annex C