BS/EN 50173-1-2018 pdf download.Information technology-Generic cabling systems Part 1 : General requirements.
5.2.4.4 Delay skew
For some applications which use transmitting or receiving channels containing multiple optical fibres, there are application specific limits for the delay skew between all the optical fibres in such channels. See Annex F for details.
6 Reference implementations for backbone cabling
6.1 General
This clause describes implementations of generic bacicbone cabling that utilise components referenced in Clauses 7, 8 and 9. These reference implementations meet the requirements of Clause 4 and, when installed in accordance with EN 50174 series of standards, meet the channel transmission performance requirements of 5.2 when subjected to the relevant environmental classifications of 5.1.
To ensure the integrity of the environmental performance of the cabling components, compatibility between cabling components shall be assured by design and in accordance with EN 50174-1.
6.2 Balanced cabling
6.2.1 General
Balanced cabling components referenced in Clauses 7, 8 and 9 are defined in terms of Category. In the reference implementations of this clause, the components used in each cabling channel shall have the same nominal characteristic impedance in accordance with 7.3.
The reference implementations described in this clause contain reductions in channel length where operating temperatures are in excess of 20 C. In order to maintain specific channel lengths under such conditions (due to the effect of ambient temperature and/or the impact of applications supported by the cabling):
a) cables can be specified with lower insertion loss specifications than those detailed in this clause and/or;
b) appropriate conditions can be provided to reduce the operating temperature of the channel (EN 50174-2 provides requirements and recommendations for installation planning and pi’actice to support remote powering applications).
Cables and connections of different Categories can be mixed within a channel however the resultant cabling performance will be determined by the Category of the lowest performing component.
6.2.2 Component choice
The selection of balanced cabling components will be determined by the channel lengths required and the
Class of applications to be supported. Refer to F.1 for guidance.
6.2.3 Dimensions
When more than one cabled optical fibre Category is used in a cabling subsystem the cabling shall be marked to allow each cabling Category to be clearly identified.
6.4.2 Component choice
The selection of optical fibre components shall be determined by the channel lengths required and the applications to be supported. Refer to Annex F for guidance.
6.4.3 DimensIons
The model of Figure 7 is applicable to backbone optical fibre cabling.
Maximum channel length is defined by the restrictions for the cabled optical fibre Category used, see Annex F.
Subject to that restriction, the maximum length for a given channel design depends upon the maximum channel insertion loss (or optical power budget, as applicable) of the application and the total attenuation allocated to connecting hardware.
NOTE Connecting hardware used to terminate fixed optical cabling can contain mated connections and splices (permanent or re-useable) and that cross-connects can compnse re-useable splices.
7 Cable requirements
7.1 General
This clause defines the minimum requirements for.
a) cables installed within generic cabling subsystems as specified within the reference implementations specified in the standards in the EN 50173 series;
b) flexible balanced cables to be assembled as cords as specified in Clause 9 and as specified within the reference implementations specified in the standards in the EN 50173 series;
c) balanced cables or cable elements to be used as jumpers.
Balanced cables shall meet the generic specification EN 50288-1 and the sectional specifications as defined in 7.3.
Coaxial cables shall meet the generic specification EN 50117-1 and the additional requirements defined in
7.4.
Optical fibre cables shall meet the generic specification EN 60794-1-1 and the sectional specifications as defined in 7.5.
For the purposes of the reference implementations specified in this, and in other parts of the EN 50173 series of standards, it is assumed that all cable elements within a cable are of the same performance Category.BS/EN 50173-1-2018 pdf download.
BS/EN 50173-1-2018 pdf download
PS:Thank you for your support!
