BS EN IEC 63267-2-1:2024

1 Scope This part of IEC 63267 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 .