IEC TR 62901:2016 pdf free.Guide for the selection of drop cables.
This Technical Report defines the term “drop cable”, describes the application spaces and the performance requirements as a consequence of the different applications. Cable design options which result from specific applications which are not yet described in the existing product specifications will be explained.
This technical report also gives some guidance on cable testing with focused attention on cable performance requirements which are not covered by existing standards yet.
This technical report is not intended to be used as a product standard.
4 Application spaces
4.1 General
Clause 4 describes most of the different ways commonly used to connect the end user to the distribution cable.
4.2.1 General
In some countries, the installation of fibre optic aerial drop cable is the most preferred option because of the relatively low effort compared to other methods like installation in ducts, direct burying, etc. Especially when the distribution cable has been installed between poles, ills common practice to also use an aerial installation for the last few meters from the NAP to the building. The connection to the NAP can either be done by splicing individual fibres to the NAP, or using field-installable connectors, or using preconnectorized cables when the NAP is designed to access the branched fibres via already installed connectors. Normally, only lower fibre counts (e.g. 1 to 8 optical fibres) are required. The distances are short (typically between 20 m and 100 m), thus the span lengths between the poles are also short (15 m to 50 m). Depending on the preferred installation method, fibre optical cables can be installed as self- supporting cables, lashed cables or suspended cables.
Even though the span length is short, ice and wind loads have to be taken into account especially when stringent sag requirements are to be fulfilled.
Cables with a black sheath are typically used for outdoor installations. The black colour is the result of the addition of “carbon black”. A concentration of approximately 2,5 % ensures the long term stability against UV radiation. When other sheath colours are used (e.g. for a better appearance) UV stabilizers have to be added. The functionality of those stabilizers has to be demonstrated by appropriate test procedures.