IEC 60793-2-10:2015 pdf download – Optical fibres – Part 2-10: Product specifications – Sectional specification for category A1 multimode fibres.
1 Scope This part of IEC 60793 is applicable to optical fibre types A1 a, A1 b, and A1 d. These fibres are used or can be incorporated in information transmission equipment and optical fibre cables. Type A1 a applies to 50/1 25 µm graded index fibre. Three bandwidth grades are defined as A1 a.1 , A1 a.2 and A1 a.3. Each of these bandwidth grades is defined for two levels of macrobend loss performance that are distinguished by “a” or “b” suffix. Those with suffix “a” are specified to meet traditional macrobend loss performance levels. Those with suffix “b” are specified to meet enhanced macrobend loss (i.e. lower loss) performance levels. Type A1 b applies to 62,5/1 25 µm graded index fibre and A1 d applies to 1 00/1 40 µm graded index fibre. Other applications include, but are not restricted to, the following: short reach, high bit-rate systems in telephony, distribution and local networks carrying data, voice and/or video services; on-premises intra-building and inter-building fibre installations including data centres, local area networks (LANs), storage area networks (SANs), private branch exchanges (PBXs), video, various multiplexing uses, outside telephone cable plant use, and miscellaneous related uses. Three types of requirements apply to these fibres: • general requirements, as defined in IEC 60793-2; • specific requirements common to the category A1 multimode fibres covered in this standard and which are given in Clause 3; • particular requirements applicable to individual fibre types or specific applications, which are defined in the normative family specification annexes.
For attenuation coefficient and modal bandwidth, the family specification contains ranges of specifiable values instead of fixed limits. The actual values of the maximum attenuation coefficient and minimum modal bandwidth, at both 850 nm and 1 300 nm (or just at one of these wavelengths) are to be agreed between supplier and customer. For commercial purposes, the modal bandwidth is linearly normalized to 1 km. For guidance purposes on bandwidth, Table H.1 shows a number of internationally standardised applications supported by A1 fibres, and Table H.2 gives a (limited) number of frequently used commercial bandwidth specifications for A1 a and A1 b fibres. The indicated maximum attenuation values apply to uncabled optical fibres; for the maximum cabled attenuation values, reference is made to IEC 60794-1 -1 , which can be used in conjunction with this standard. Remarks on the specification of modal bandwidth: Care should be taken in writing dual wavelength bandwidth specifications. For category A1 fibres, the bandwidth at 850 nm may be related to the bandwidth at 1 300 nm in a way shown in Figure 1 , depending on the refractive index parameter, g, (see IEC 60793-2:201 1 , 5.1 ). The shaded region under the curve of Figure 1 can be defined as the dual window area. In this area, regions X, Y, and Z are examples of where a fibre manufacturer may choose to optimise the process. That is, centre the production at 850 nm, 1 300 nm, or between these two wavelengths. Due to this optimisation of the manufacturing process, there will be combinations of bandwidth that are not possible. For example, it is practically impossible to produce a fibre with the maximum of both indicated bandwidth ranges (e.g. 800 MHz ⋅ km/1 000 MHz ⋅ km for A1 b multimode fibres).
These tests are normally conducted periodically as type-tests for a fibre and coating design. Unless otherwise indicated, the recovery period allowed between the completion of the environmental exposure and performing the attribute measurements shall be as stated in the particular environmental test method. 4.4.2 Mechanical environmental requirements (common to all fibres in category A1 ) 4.4.2.1 General These tests are, in practice, the most severe requirements amongst the environments defined in Table 8. Tables 1 0, 1 1 , and 1 2 give the prescriptions for strip force, tensile strength and stress corrosion susceptibility respectively. 4.4.2.2 Strip force The following attributes shall be verified following removal of the fibre from the particular environment.