IEC 61977 pdf download.Fibre optic filters – Generic specification
4.1.6 Normative reference extensions
Normative reference extensions are used to identify independent standards specifications or other reference documents integrated into blank detail specifications. Unless a specified exception is noted, additional requirements imposed by an extension are mandatory. Usage is primarily intended to merge associated components to form hybrid devices, or integrated functional application requirements that are dependent on technical expertise other than fibre optics. Published reference documents produced by the International Telecommunication Union (ITU), consistent with the scope statements of the relevant IEC specification series may be used as an extension. Published documents produced by other regional standardisation bodies such as the Telecommunications Industry Association (TIA), the European Telecommunications Standards Institute (ETSI), Japanese Industrial Standards (JIS) etc, may be referenced in a bibliography attached to the generic. Some optical fibre filter configurations require special qualification provisions which shall not be imposed universally. This accommodates individual component design configurations, specialised field tooling, or specific application processes. In this case requirements are necessary to guarantee repeatable performance or adequate safety, and provide additional guidance for complete product specification. These extensions are mandatory whenever used to prepare, assemble or install an optical fibre splice either for field application usage or preparation of qualification test specimens. The relevant specification shall clarify all stipulations. However, design and style dependent extensions shall not be imposed universally. In the event of conflicting requirements, precedence, in descending order, shall be generic over mandatory extension, over blank detail, over detail, over application specific extension.The following is an example of an optical connector extension: • Using IEC 61754-4 and IEC 61754-2 to partially define a future IEC 60874-XX specification for a duplex type “SC/BFOC/2,5” hybrid connector adapter. Some commercial or residential building applications may require direct reference to specific safety codes and regulations or incorporate other specific material flammability or toxicity requirements for specialised locations. Specialised field tooling may require an extension to implement specific ocular safety, elec- trical shock or burn hazard avoidance requirements, or require isolation procedures to prevent potential ignition of combustible gases.
4.2.1 Symbols Graphical and letter symbols shall, whenever possible, be taken from IEC 60027, IEC 60617 and IEC 61748 unless superseded by this specification. 4.2.2 Specification system This specification is part of the IEC specification system. Subsidiary specifications shall consist of blank detail specifications and detail specifications. This system is shown in table 1. There are no sectional specifications for filters.220.127.116.11 Blank detail specification The blank detail specification lists all of the parameters and features applicable to a filter including the type, operating characteristics, housing configurations, test methods and performance requirements. The blank detail specification is applicable to any filter design and quality assessment requirement. The blank detail specification contains the preferred format for stating the required information in the detail specification. 18.104.22.168 Detail specification A specific fibre optic filter is described by a corresponding detail specification, which is prepared by filling in the blanks of the detail specification.4.2.3 Drawings The drawings and dimensions given in the detail specifications shall not restrict detail construction nor be used as manufacturing drawings. 22.214.171.124 Projection system Either first angle or third angle projection shall be used for the drawings in documents covered by this specification. All drawings within a document shall use the same projection system and the drawings shall state which system is used. 126.96.36.199 Dimensional system All dimensions shall be given in accordance with ISO 129, ISO 286 and ISO 1101. The metric system shall be used in all specifications. Dimensions shall not contain more than five significant digits. When units are converted, a note shall be added in each detail specification. 4.2.4 Test and measurements 188.8.131.52 Test and measurement procedures The test and measurement procedures for optical, mechanical, climatic and environmental characteristics of filters to be used shall be defined and selected preferentially from IEC 61300 series standards. The size measurement method to be used shall be specified in the detail specification for dimensions which are specified within a total tolerance zone of 0,01 mm or less.