IEC 61753-031-6:20 14（E）包含非波长选择性分支器件（NWBD）应满足的最低初始测试和测量要求以及严重性，以便归类为满足本标准的要求。这些要求涵盖用于IEC O类环境（N为分支端口数量）的平衡双向非连接器单模1xN和2xN非波长选择性分支器件，特别是但不限于用于PON应用。对于平衡NWBD，考虑两个衰减和均匀性性能类别: -A类（高级类），满足更严格的要求（即用于扩展覆盖PON应用）和 -B类(标准类)用于标准应用(即，正常到达PON应用)。这些要求还涵盖了不平衡双向非连接器单模非波长选择性分支器件，然而，不平衡分支器件的规格仅限于1x2和2x2器件，因为它们是最常用的器件。IEC 61753-031-6的第二版取消并取代了2008年发布的第一版，构成了技术修订。与上一版相比，此版本包括以下重大技术变更: -删除引言； -更新和扩展范围，以反映为平衡NWBD引入两个衰减和均匀性性能等级，而不是市场上的分支器件技术； -更新的规范性参考文献清单； -对两种类型的光谱带的更简化的介绍；-第5条（性能要求）已更新和扩展，以反映为平衡NWBD引入两个衰减和均匀性性能等级； -简化测试项目，排除湿热（稳态）和性能要求冲击测试； -对附件A进行了修改，引入了衰减和均匀性的计算要求和最低要求。 关键词:非波长选择性分支器件（NWBD），IEC O类环境

IEC 61753-031-6:2014(E) contains the minimum initial tests and measurement requirements and severities which a non-wavelength selective branching device (NWBD) should satisfy in order to be categorized as meeting the requirements of this standard. The requirements cover balanced bidirectional non-connectorized single-mode 1xN and 2xN non-wavelength-selective branching devices for use in an IEC category O environment (N is the number of branching ports), especially but not exclusively used for PON application. For balanced NWBD, two attenuation and uniformity performance classes are considered:
- class A (premium class) which meets more restrictive requirements (i.e. for extended reach PON application) and
- class B (standard class) for standard application (i.e. normal reach PON application). The requirements also cover unbalanced bidirectional non-connectorized single-mode non-wavelength-selective branching devices, however the specifications of unbalanced branching devices are limited to 1x2 and 2x2 devices because they are the most commonly used. This second edition of IEC 61753-031-6 cancels and replaces the first edition published in 2008 and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- deletion of the Introduction;
- an updated and extended scope to reflect an introduction of two attenuation and uniformity performance classes for balanced NWBD instead of branching device technologies on the market;
- an updated list of normative references;
- a more simplified introduction to the two types of spectral bands;
- Clause 5, Performance requirements, has been updated and extended to reflect the introduction of two attenuation and uniformity performance classes for balanced NWBD;
- simplified test items to exclude tests for damp heat (steady state) and impact for performance requirements;
- Annex A has been changed to introduce the calculated and minimum requirements for attenuation and uniformity. Keywords: non-wavelength selective branching device (NWBD), IEC category O environment