SIST EN 50173-20:2023

Information technology - Generic cabling systems - Part 20: Alternative cabling configurations

1.1   Scope
This document specifies:
a)   configurations of cabling which use components meeting the requirements of EN 50173-1 but which do not conform to the structure of generic cabling specified in the premises-specific parts of EN 50173-X;
b)   channel transmission and environmental performance requirements including those by reference to EN 50173-1.
Test procedures to verify conformance of the balanced cabling configurations to the cabling transmission performance requirements of this document are provided in prEN 50697.
Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this document and are covered by other standards and regulations. However, information given in this document can be of assistance in meeting these standards and regulations.
1.2   Conformance
For a cabling to conform to this document the following applies:
a)   The configuration and structure of the cabling conforms to the requirements of Clause 4.
b)   Environmental performance meets the requirements of 5.1.
c)   Transmission performance meets the requirements of 5.2.
For balanced cabling, test methods to assess conformance with the transmission performance requirements are specified in prEN 50697.
For optical fibre cabling, test methods to assess conformance with the transmission performance requirements are specified in Annexes A, B and C.
d)   The requirements of EN 50174 series standards and EN 50310 are met.
This document provides the requirements and recommendations for testing, while the requirements for the sampling levels are provided in EN 50174-1:2018, Annex F.
The test parameters to be measured, the sampling levels and the treatment of measured results to be applied for a particular installation are defined in the installation specification and quality plans for that installation prepared in accordance with EN 50174 1.

Informationstechnik - Anwendungsneutrale Kommunikationskabelanlagen - Teil 20: Alternative Verkabelungskonfigurationen

Technologies de l'information - Systèmes de câblage générique - Partie 20: Configurations alternatives de câblage

1.1   Domaine d’application
Le présent document spécifie:
a)   les configurations de câblage qui utilisent des composants satisfaisant aux exigences de l’EN 50173-1, mais qui ne sont pas conformes à la structure des parties de l’EN 50173-X spécifiques aux systèmes de câblage générique déployés dans des locaux;
b)   les exigences de transmission de canaux et de performances environnementales, y compris celles incluses en faisant référence à l’EN 50173-1.
Les procédures d’essai visant à vérifier la conformité des configurations de câblage à paires symétriques aux exigences de performances de transmission du câblage, données dans le présent document, sont détaillées dans le prEN 50697.
Les exigences relatives à la sécurité et à la compatibilité électromagnétique (CEM) ne relèvent pas du domaine d’application du présent document et sont couvertes par d’autres normes et réglementations. Cependant, les informations données dans le présent document peuvent être utiles pour assurer la conformité à ces normes et réglementations.
1.2   Conformité
Les considérations suivantes s’appliquent pour qu’un câblage soit conforme au présent document.
a)   La configuration et la structure du câblage satisfont aux exigences énoncées à l’Article 4.
b)   Les performances environnementales satisfont aux exigences de 5.1.
c)   Les performances de transmission satisfont aux exigences de 5.2.
Pour un câblage à paires symétriques, les méthodes d’essai visant à évaluer la conformité aux exigences relatives aux performances de transmission sont spécifiées dans le prEN 50697.
Pour un câblage à fibres optiques, les méthodes d’essai visant à évaluer la conformité aux exigences relatives aux performances de transmission sont spécifiées dans les Annexes A, B et C.
d)   Les exigences des normes de la série EN 50174 et de l’EN 50310 sont respectées.
Le présent document donne les exigences et les recommandations pour les essais, tandis que les exigences relatives aux niveaux d’échantillonnage sont données dans l’Annexe F de l’EN 50174-1:2018.
Les paramètres d’essai à mesurer, les niveaux d’échantillonnage et le traitement des résultats mesurés à appliquer pour une installation spécifique sont définis dans la spécification d’installation et les plans qualité concernant cette installation, préparés conformément à l’EN 50174 1.

Informacijska tehnologija - Generični kabelski sistemi - 20. del: Alternativne kabelske konfiguracije

Ta dokument določa:
a)   kabelske konfiguracije s komponentami, ki izpolnjujejo zahteve standarda EN 50173-1, vendar niso v skladu s strukturo generičnih kablov, določenih v delih standarda EN 50173-X, ki se navezujejo na prostore;
b)   zahteve za kanalni prenos in okoljske lastnosti, vključno s tistimi, ki se sklicujejo na standard EN 50173-1.
Preskusni postopki za preverjanje skladnosti uravnoteženih kabelskih konfiguracij z zahtevami glede zmogljivosti kabelskega prenosa iz tega dokumenta so navedeni v predlogu standarda prEN 50697.
Varnostne zahteve in zahteve za elektromagnetno združljivost (EMC) ne spadajo na področje uporabe tega dokumenta ter so obravnavane v drugih standardih in predpisih. Vendar so lahko informacije iz tega dokumenta v pomoč pri izpolnjevanju teh standardov in predpisov.
1.2   Skladnost
Za napeljavo kablov v skladu s tem dokumentom velja naslednje:
a)   Konfiguracija in struktura kablov je v skladu z zahtevami iz točke 4.
b)   Okoljske lastnosti izpolnjujejo zahteve iz točke 5.1.
c)   Zmogljivost prenosa izpolnjuje zahteve iz točke 5.2.
Za uravnotežene kable so preskusne metode za oceno skladnosti z zahtevami glede zmogljivosti prenosa določene v predlogu standarda prEN 50697.
Za optične kable so preskusne metode za oceno skladnosti z zahtevami glede zmogljivosti prenosa določene v dodatkih A, B in C.
d)   Izpolnjene so zahteve skupine standardov EN 50174 in EN 50310.
Ta dokument podaja zahteve in priporočila za preskušanje, medtem ko so zahteve za ravni vzorčenja navedene v dodatku F standarda EN 50174-1:2018.
Preskusni parametri, ki jih je treba izmeriti, ravni vzorčenja in obdelava rezultatov meritev, ki se uporabljajo za določeno inštalacijo, so opredeljeni v specifikaciji naprave in načrtih kakovosti za to inštalacijo, pripravljenih v skladu s standardom EN 50174-1.

General Information

• Status: Published
• Publication Date: 01-Dec-2022
• ICS: 33.040.50 - Lines, connections and circuits
• ICS: 35.110 - Networking
• Technical Committee: ELI - Electrical and communication installations
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2022
• Due Date: 05-Feb-2023
• Completion Date: 02-Dec-2022
• Ref Project: EN 50173-20:2022 - Information technology - Generic cabling systems - Part 20: Alternative cabling configurations

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 50173-20:2023
01-januar-2023
Informacijska tehnologija - Generični kabelski sistemi - 20. del: Alternativne
kabelske konfiguracije
Information technology - Generic cabling systems - Part 20: Alternative cabling
configurations
Informationstechnik - Anwendungsneutrale Kommunikationskabelanlagen - Teil 20:
Alternative Verkabelungskonfigurationen
Technologies de l'information - Systèmes de câblage générique - Partie 20:
Configurations alternatives de câblage
Ta slovenski standard je istoveten z: EN 50173-20:2022
ICS:
33.040.50 Vodi, zveze in tokokrogi Lines, connections and
circuits
35.110 Omreževanje Networking
SIST EN 50173-20:2023 en,fr

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50173-20:2023
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SIST EN 50173-20:2023
EUROPEAN STANDARD EN 50173-20
NORME EUROPÉENNE
EUROPÄISCHE NORM October 2022
ICS 35.110
English Version
Information technology - Generic cabling systems - Part 20:
Alternative cabling configurations

Technologies de l'information - Systèmes de câblage Informationstechnik - Anwendungsneutrale

générique - Partie 20: Configurations alternatives de Kommunikationskabelanlagen - Teil 20: Alternative

câblage Verkabelungskonfigurationen

This European Standard was approved by CENELEC on 2022-10-17. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN 50173-20:2022 E
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
Contents Page

European foreword ............................................................................................................................................. 4

Introduction ......................................................................................................................................................... 5

1 Scope ..................................................................................................................................................... 8

2 Normative references ............................................................................................................................. 8

3 Terms, definitions and abbreviations ..................................................................................................... 8

3.1 Terms and definitions ............................................................................................................................. 8

3.2 Abbreviations .......................................................................................................................................... 9

3.3 Symbols .................................................................................................................................................. 9

4 Conformance ........................................................................................................................................ 10

5 Cabling configurations .......................................................................................................................... 10

5.1 Direct attach cabling ............................................................................................................................. 10

5.1.1 General ..................................................................................................................................... 10

5.1.2 Performance requirements ....................................................................................................... 11

5.1.3 Design objectives ...................................................................................................................... 11

5.2 End-to-end (E2E) link ........................................................................................................................... 12

5.2.1 General ..................................................................................................................................... 12

5.2.2 Performance requirements ....................................................................................................... 13

5.2.3 Design objectives ...................................................................................................................... 13

5.3 Modular plug terminated links (MPTL) ................................................................................................. 14

5.3.1 General ..................................................................................................................................... 14

5.3.2 Performance requirements ....................................................................................................... 15

5.3.3 Design objectives ...................................................................................................................... 15

6 Cabling performance ............................................................................................................................ 16

6.1 Environmental performance ................................................................................................................. 16

6.2 Transmission performance ................................................................................................................... 16

6.2.1 Balanced cabling performance ................................................................................................. 16

6.2.2 Optical fibre cabling performance ............................................................................................. 17

7 Performance verification ....................................................................................................................... 17

Annex A (normative) Transmission performance requirements for direct attach cabling ............................... 18

A.1 Balanced cabling of Class D to Class II ............................................................................................... 18

A.2 Optical fibre cabling .............................................................................................................................. 19

Annex B (normative) Transmission performance limits for E2E links ............................................................. 20

B.1 Balanced cabling .................................................................................................................................. 20

B.2 Optical fibre cabling .............................................................................................................................. 21

Annex C (normative) Transmission performance limits for modular plug terminated links ............................. 22

C.1 Balanced cabling .................................................................................................................................. 22

C.2 Optical fibre cabling .............................................................................................................................. 23

Annex D (normative) Testing procedures to assess conformance ................................................................. 24

D.1 General ................................................................................................................................................. 24

D.2 Performance testing ............................................................................................................................. 24

Bibliography ...................................................................................................................................................... 28

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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
Figures

Figure 1 — Schematic relationship between the EN 50173 series and other relevant standards .................... 6

Figure 2 — Direct attach cabling configuration................................................................................................ 10

Figure 3 — E2E link configurations ................................................................................................................. 13

Figure 4 — MPTL configuration ....................................................................................................................... 14

Tables

Table 1 — Contextual relationship between EN 50173 series and other standards relevant for information

technology cabling systems ............................................................................................................................... 6

Table A.1 — Transmission performance requirements for direct attach cabling of Class D to Class II.......... 18

Table B.1 — Transmission performance requirements for E2E links ............................................................. 20

Table C.1 — Transmission performance requirements for MPTL of Class D to Class II ................................ 22

Table D.1 — Test regime for reference conformance and installation conformance for balanced cabling .... 26

Table D.2 — Test regime for reference conformance and installation conformance for optical fibre cabling . 27

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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
European foreword

This document (EN 50173-20:2022) has been prepared by CLC/TC 215, "Electrotechnical aspects of

telecommunication equipment".
The following dates are fixed:
• latest date by which this document has to be (dop) 2023-10-17
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) 2025-10-17
conflicting with this document have to be
withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Any feedback and questions on this document should be directed to the users’ national committee. A complete

listing of these bodies can be found on the CENELEC website.
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
Introduction

This document contains requirements for cabling configurations which use cabling components meeting the

requirements of EN 50173-1 but in configurations that do not conform to the structure of generic cabling in the

premises-specific documents EN 50173-2 to EN 50173-6.
These configurations are described as:
a) direct attach cabling;
b) end-to-end (E2E) links;
c) modular plug terminated links (MPTL).

The configurations of this document do not replace the generic cabling solutions of EN 50173-2, EN 50173-3,

EN 50173-4, EN 50173-5 and EN 50173-6.

The transmission performance of these configurations implemented using balanced cabling components is

specified in terms of Class in order to indicate their ability to support the relevant applications of EN 50173-1.

The transmission performance of these configurations implemented using optical fibre cabling components is

not specified and refers the application support parameters of EN 50173-1.

Remote powering is covered in EN 50174-1 (Planning) and in EN 50174-2 (installation).

The cabling configurations of this document are passive systems and cannot be tested for EMC compliance

individually. Application-specific equipment, designed for one or more cabling media, is required to meet

relevant EMC standards on those media. Care should be taken that the installation of any of those media in a

cabling system does not degrade the characteristics of the cabling. The installation methods of EN 50174

series should be used to minimise the effect of electromagnetic disturbances.

Figure 1 and Table 1 show the schematic and contextual relationships between the standards produced by

TC 215 for information technology cabling, namely:
1) this and other parts of the EN 50173 series;
2) installation (EN 50174 series);
3) bonding (EN 50310).
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)

Figure 1 — Schematic relationship between the EN 50173 series and other relevant standards

Table 1 — Contextual relationship between EN 50173 series and other standards relevant for

information technology cabling systems
Building design Generic cabling Specification Installation Operation phase
phase design phase phase phase
EN 50174-1
Planning phase
EN 50174-2
EN 50173-XX
EN 50310 EN 50174-3 EN 50174-1
EN 50174-2
EN 50310
EN 50174-3
EN 50310
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)

In addition, a number of Technical Reports have been developed to support or extend the application of these

standards, including:
— CLC/TR 50173-99-1, Cabling guidelines in support of 10 GBASE-T;

— CLC/TR 50173-99-2, Information technology — Implementation of BCT applications using cabling in

accordance with EN 50173-4;

— CLC/TR 50173-99-3, Information technology — Generic cabling systems — Part 99-3: Home cabling

infrastructures up to 50 m in length to support simultaneous and non simultaneous provision of

applications.

In addition, a number of cabling design standards have been developed using components of EN 50173-1 (e.g.

EN 50098 series and EN 50700).
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
1 Scope
This document specifies:

a) configurations of cabling which use components meeting the requirements of EN 50173-1 but do not

conform to the structure of generic cabling specified in the premises-specific documents EN 50173-2 to

EN 50173-6;

b) channel transmission and environmental performance requirements including those by reference to

EN 50173-1.

NOTE The configurations of this document do not replace the generic cabling solutions of EN 50173-2, EN 50173-3,

EN 50173-4, EN 50173-5 and EN 50173-6.

Test procedures to verify conformance of the balanced cabling configurations to the cabling transmission

performance requirements of this document are provided in EN 50697.

Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this document and are

covered by other standards and regulations.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes

requirements of this document. For dated references, only the edition cited applies. For undated references,

the latest edition of the referenced document (including any amendments) applies.

EN 50173-1:2018, Information technology — Generic cabling systems — Part 1: General requirements

EN 50174-1:2018, Information technology — Cabling installation — Part 1: Installation specification and quality

assurance
EN 50174 (series), Information technology — Cabling installation
EN 50310, Telecommunications bonding networks for buildings and other structures

EN 50697, Information technology — Measurement of end-to-end links, modular plug terminated links and

direct attach cabling

EN 60603-7(series), Connectors for electronic equipment — Part 7: Detail specification for 8-way, shielded,

free and fixed connectors
3 Terms, definitions and abbreviations
3.1 Terms and definitions

For the purposes of this document the terms and definitions of EN 50173-1 and EN 50174-1 and the following

apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
As impacted by EN 50174-1:2018/A1:2020.
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
3.1.1
bulkhead connector

connection that serves as an interconnection point located through an enclosure wall

3.1.2
direct attach cabling

cable with free connectors at each end, and with no intermediate connecting hardware, that connects two

pieces of equipment
3.1.3
end-to-end link
end-to-end transmission path terminated with a free connector on each end

Note 1 to entry: It can be formed by structured cabling based on passive components including the portion of the end

connection that is attached to the link and the portion of the end connection that is attached to the end equipment.

3.1.4
modular plug terminated link

link terminated with a free connector on one end and a fixed connector at the other end

3.2 Abbreviations

For the purposes of this document the abbreviations of EN 50173-1 and EN 50174-1 and the following apply.

CA coupling attenuation
E2E end-to-end
ffs for further study
MPTL modular plug terminated link
3.3 Symbols
For the purposes of this document the following symbols apply.
bulkhead connector assembly with connections separated by ≥ 0,1 m (acting as two
connections)
bulkhead connector assembly with connections separated by < 0,1 m (acting as one
connection)
connection
fixed connector
free connector
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
4 Conformance
For a cabling to conform to this document the following applies:

a) The configuration and structure of the cabling shall conform to the requirements of Clause 5.

b) The environmental performance shall meet the requirements of 6.1.
c) The transmission performance shall meet the requirements of 6.2.

For balanced cabling, test methods to assess conformance with the transmission performance

requirements are specified in EN 50697.

For optical fibre cabling, test methods to assess conformance with the transmission performance

requirements are specified in Annexes A, B and C.
d) The requirements of EN 50174 series standards and EN 50310 shall be met.

This document provides the requirements and recommendations for testing, while the sampling levels shall

comply with EN 50174-1:2018, Annex F.

The test parameters to be measured, the sampling levels and the treatment of measured results to be applied

for a particular installation shall be defined in the installation specification and quality plans for that installation

prepared in accordance with EN 50174-1.
5 Cabling configurations
5.1 Direct attach cabling
5.1.1 General

Direct attach cabling can be used to connect items of information technology equipment but does not constitute

any part of, and cannot be exchanged with any part of, the generic cabling structures specified in EN 50173-2,

EN 50173-3, EN 50173-4, EN 50173-5 or EN 50173-6.

The configuration of direct attach cabling is shown in Figure 2 and comprises a length L of cable terminated in

free connectors. As a result, it can have the physical attributes of an equipment cord or patch cord as defined

in EN 50173-1 but its function is different.

The performance of the terminating free connectors is included in the specification of direct attach cabling.

Figure 2 — Direct attach cabling configuration
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
5.1.2 Performance requirements
5.1.2.1 Balanced direct attach cabling
See 6.1, 6.2.1.1 and 6.2.1.2.
5.1.2.2 Optical fibre direct attach cabling
See 6.1, 6.2.2.1 and 6.2.2.2.
5.1.3 Design objectives
5.1.3.1 General

Direct attach cabling connects a single port of one device to a single port of another device.

Although direct attach cabling can appear a simple and cost-effective method of providing connections, for

several reasons this cabling type should only be used for connections within the same or adjacent cabinets,

frames or racks.

Direct attach cabling is often not reusable as equipment types and locations change and a particular direct

attach cabling can have a limited lifetime. Continuous changes to the required interconnections increase both

the planning and the operational resources required for each change and increases the risk of interfering with

other infrastructures - including those for environmental control.
Direct attach cabling shall only be used subject to the following restrictions:

a) the mechanical performance of cables used for direct attach cabling shall meet the requirements of the

installation environment (e.g. pathway systems);

b) free connectors shall be protected against damage during installation, disconnection or removal;

c) direct attach cabling shall be managed so as to avoid mechanical damage and/or accidental disconnection

to adjacent connections during insertion or removal;

d) direct attach cabling shall be labelled at both ends to show their origin and destination in accordance with

the level 3 administration requirements of EN 50174-1:2018 ;

e) the impact of direct attach cabling on the fire load of cabling shall be assessed and mitigation provided if

necessary;

f) direct attach cabling shall not be located where they restrict cooling airflow towards active equipment.

5.1.3.2 Balanced direct attach cabling

Balanced direct attach cabling can be employed to connect any two items of information technology equipment.

Balanced cabling implementations provide generic application support for the transmission of information using

an application listed in EN 50173-1:2018, Annex F, and belonging to Classes A to F , I and II.

A more obvious, and lower risk, solution would be to use a factory-terminated cord of the required Category

necessary to deliver the required application Class as specified in EN 50173-1.

Where there are concerns about the “installability” of a pre-terminated cable, e.g. due to routing restrictions, a

user can terminate a cable in-situ. In such a situation the user can obtain knowledge regarding the performance

of the terminating free connectors applied to the cable following its installation.

The performance requirements are specified in Annex A, because direct attach cabling is required to act as a

direct connection rather than a component within a cabling subsystem.

The transmission performance requirements of Annex A are different to those of a patch cord of

EN 50173-1:2018, Clause 9, being more comprehensive but not as stringent as those of a cord in accordance

with EN 50173-1.
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)

As a result, compliance of direct attach cabling to the performance requirements of Annex A does not allow

direct attach cabling to be used as cords within any generic cabling channel since they deplete the channel

performance preventing any other cabling components to be included within the channel.

Where direct attach cabling is proposed to be used but which could be confused with the cords of generic

cabling then either:

a) the direct attach cabling shall be labelled or otherwise identified to indicate its nature;

b) cords in accordance with EN 50173-1 (of the appropriate Category) shall be used in place of the direct

attach cabling.

Failure to apply one of these solutions would risk potential disruption to generic cabling function and associated

costs of downtime and fault-finding.
5.1.3.3 Optical fibre direct attach cabling

Optical fibre direct attach cabling shall be constructed using components with performance specified in

EN 50173-1.

As such optical fibre direct attach cabling is required to meet the requirements of a cord in accordance with

EN 50173-1. However, it may only be exchanged with a cord within any generic cabling channel if the length

of resulting channel meets the requirements of the application detailed in EN 50173-1:2018, Annex F.

5.2 End-to-end (E2E) link
5.2.1 General

The E2E link concept represents an extension of the configurations of generic cabling in EN 50173-3:2018,

Annexes C and D.

The most basic E2E link comprises a length L of cable terminated in free connectors. This is described as a

“1-segment, 2-connection E2E link” in Figure 3. Functionally, it replaces a cabling sub-system and acts as a

channel between transmission equipment and terminal equipment as defined in EN 50173-1.

The important difference is that installation of an E2E link can require the termination of the cable following

installation and the performance requirements of Annex B have to include the free connectors at each end of

the E2E link. For this reason, the most basic configuration is described as “1-segment, 2-connection E2E link”

even though there are no connections in the channel as defined in EN 50173-1.

EN 50173-3:2018, Annexes C and D, present increasingly complex variations of total length L with up to 4

mated connections between the free connectors at either end of the E2E link (leading to a description as 6-

connection E2E links). Examples of these configurations are shown in Figure 3.
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SIST EN 50173-20:2023
EN 50173-20:2022 (E)
Figure 3 — E2E link configurations
5.2.2 Performance requirements
5.2.2.1 Balanced E2E links
See 6.1, 6.2.1.1 and 6.2.1.3.

6.2.1.3 contains the requirements for a 6 connection E2E link which are intended to be applied to all

configurations of E2E link.
5.2.2.2 Optical fibre E2E links
See 6.1, 6.2.2.1 and 6.2.2.3.
5.2.3 Design objectives
5.2.3.1 General

E2E links do not meet the structural conformance requirements of EN 50173-2, EN 50173-3, EN 50173-4,

EN 50173-5 or EN 50173-6.

An E2E link connects a single port of one device to a single port of another device. It is, in essence, a form of

direct attach cabling.

However, an E2E link may contain many elements and is a direct replacement for a generic cabling channel

and is implemented for simplicity of installation in industrial spaces where there is no opportunity to

accommodate the fixed connections associated with the distributors and or TOs. This is shown in

EN 50173-3:2018, Annexes C and D.
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EN 50173-20:2022 (E)

It is typically installed to meet a specific equipment configuration and would be removed during reconfiguration

of that equipment – and could be terminated on site therefore justifying assessment of the terminating free

connectors.
However:

a) the resulting lack of flexibility prevents the identified advantages of moves, adds and changes associated

with the structure of generic cabling in accordance with EN 50173-2, EN 50173-3, EN 50173-4,

EN 50173-5 or EN 50173-6;

b) the impact of damage of the terminating free connectors can require the reinstallation of part, or all, of the

E2E links.

NOTE In the case of an installation according to EN 50173-1, only the cord would have to be replaced.

5.2.3.2 Balanced E2E links

Balanced cabling implementations provide generic application support for the transmission of information using

an application listed in EN 50173-1:2018, Annex F and belonging to Class A to E .

5.2.3.3 Optical fibre E2E links

Optical fibre E2E link shall be constructed using components with performance specified in EN 50173-1.

5.3 Modular plug terminated links (MPTL)
5.3.1 General

A MPTL comprises a length L of cable terminated at one end with a fixed connector and the other end with a

free connector as shown in Figure 4.
Figure 4 — MPTL configuration
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EN 50173-20:2022 (E)

The typical implementation is for the fixed connector to be associated with a distributor (e.g. Floor Distributor

in EN 50173-2) and the free connector to replace the combination of terminal equipment outlet and associated

equipment cord connecting to the terminal equipment. This is shown as a 2-connection MPTL in Figure 4.

The mechanical and electrical characteristics of the free connector shall comply with EN 60603-7 series. The

performance of the free connector is included in the specification of MPTL.
5.3.2 Performance requirements
5.3.2.1 Balanced MPTL
See 6.1, 6.2.1.1 and 6.2.1.4.
5.3.2.2 Optical fibre MPTL
See 6.1, 6.2.2.1 and 6.2.2.4.
5.3.3 Design objectives
5.3.3.1 General

An MPTL does not meet the structural conformance requirements of EN 50173-2, EN 50173-3, EN 50173-4,

EN 50173
...