DIN EN IEC 61755-3-2:2025-12

This part of IEC 61755-3-2:2024 defines the dimensional limits of the optical interface that are necessary for single-mode fibre optic connectors with 2,5 mm or 1,25 mm diameter cylindrical zirconia (ZrO2) ferrules polished at an 8° angle to meet the specific requirements for fibre-to-fibre interconnection, as defined in IEC 61755-2-2. Ferrules made from the material specified in this standard are suitable for use in all the operating service environments defined in IEC 61753-1. Ferrule dimensions and features are contained in the IEC 61754 series of fibre optic connector interface standards. There are no restrictions on the scope of this document. The standard differs from DIN EN 61755-3-2:2009-08 as follows: a) normative references have been added; b) the introduction of an additional optical interface with a different fibre core eccentricity profile. The previous revision of optical interface standard is named "Variant 1: with fibre core axis oriented towards the connector guide key". The additional optical interface is named "Variant 2: with fibre core axis not oriented towards the connector guide key"; c) statements added related to interoperability, where both variants remain intermateable within a given performance grade and are fully backwards compatible to IEC 61755-3-2:2006; d) the addition of Grade B and Grade C interface requirements for both variants; e) the addition of a descriptive statistic for the mean fibre core eccentricity (mean value) to describe the distribution of fibre core eccentricity to ensure interoperability; f) a new informative Annex B to give guidance on the expected attenuation when mated to a reference connector plug; (g) a new informative Annex C to provide guidance on simulating the attenuation of optical interfaces; h) a new informative Annex D to give guidance related to estimation of mean fibre eccentricity limits for finite production batch sizes. The optical interface plays a key role in determining the attenuation and return loss values of the connection in which it is used. Every manufacturer of optical connectors makes use of this series of standards. Operators of optical transmission systems define their quality requirements for connections by referencing this standard. Application of this document increases investment security for manufacturers and users, provides testing laboratories and manufacturers with defined specifications for testing, and ensures compatibility across manufacturers.