DIN EN IEC 63267-2-1:2025-12

This document defines a set of specified conditions for an enhanced macro bend of 50/125 µm, graded index multimode fibre optic connection that is maintained in order to satisfy the requirements of attenuation and return loss performance in a randomly mated pair of polished physically contacting (PC) fibres. An encircled flux (EF) compliant launch condition in accordance with IEC 61300-1, at an operational wavelength of 850 nm, is used for determination of performance grades, based on lateral fibre core offset, numerical aperture (NA) mismatch, and fibre core diameter (CD) variation. Fibre core angular offset is considered insignificant given the state-of-the-art and is excluded as a factor for attenuation estimation. Attenuation and return loss performance grades are defined in IEC 63267-1. 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