1、BSI Standards Publication Information technology Cabling installation Part 99-1: Remote powering PD CLC/TR 50174-99-1:2015National foreword This Published Document is the UK implementation of CLC/TR 50174-99- 1:2015. Please note: Section 6.4.1 contains a recognised error which will be corrected duri
2、ng a future revision of this document; 0.15 m should read 0.015 m. The UK participation in its preparation was entrusted to Technical Committee TCT/7, Telecommunications Installation requirements. A list of organizations represented on this committee can be obtained on request to its secretary. This
3、 publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 90499 8 ICS 35.110 Compliance with a British Standard cannot confer i
4、mmunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 June 2015. Amendments/corrigenda issued since publication Date Text affected PUBLISHED DOCUMENT PD CLC/TR 50174-99-1:2015 TECHNICAL REPORT RAPPORT TECHNIQUE
5、TECHNISCHER BERICHT CLC/TR 50174-99-1 April 2015 ICS 35.110 English Version Information technology - Cabling installation - Part 99-1: Remote powering This Technical Report was approved by CENELEC on 2015-04-06. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgar
6、ia, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerla
7、nd, Turkey and the United Kingdom. European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CENELEC All rights of exploitation in any
8、form and by any means reserved worldwide for CENELEC Members. Ref. No. CLC/TR 50174-99-1:2015 E PD CLC/TR 50174-99-1:2015CLC/TR 50174-99-1:2015 - 2 - Contents Foreword 4 Introduction . 5 1 Scope 6 2 Normative references . 6 3 Terms, definitions, abbreviations and symbology 6 3.1 Terms and definition
9、s . 6 3.2 Abbreviations . 7 3.3 Symbology . 7 4 Overview . 7 4.1 General 7 4.2 Published standards . 8 4.3 Recent developments . 9 4.4 Basic principles of remote powering . 10 4.5 Testing protocols and mathematical modelling 10 5 Application of remote powering 10 5.1 Channel length . 10 5.2 Cables o
10、f Category 5 (minimum) in EN 50173-1 11 5.3 Installation environment . 12 5.4 Cable bundles 12 5.5 Connecting hardware of Category 5 (minimum) in EN 50173-1 13 5.6 Pathways and pathway systems 13 6 Operation 14 6.1 Design margin 14 6.2 Cable bundle temperature and construction 14 6.3 Range of temper
11、ature rises 14 6.4 Installation guidance 16 6.5 Record-keeping 16 6.6 Cabling acceptance and trouble-shooting testing 16 Annex A (informative) Powering concepts . 17 A.1 Principles . 17 A.2 Mathematical treatment 17 A.3 Power dissipation . 19 Annex B (normative) Test protocol . 20 B.1 Background 20
12、B.2 Test set-up . 20 B.3 Current delivery and measurement accuracy 22 B.4 Test conditions . 22 B.5 Installation environment . 22 B.6 Data submission. 23 PD CLC/TR 50174-99-1:2015 - 3 - CLC/TR 50174-99-1:2015 Annex C (normative) Temperature rise modelling . 25 C.1 Model basics 25 C.2 Power dissipated
13、 (P) 25 C.3 Temperature difference from ambient temperature to bundle surface (T u ) . 26 C.4 Temperature difference from bundle surface to bundle centre (T th ) 26 C.5 Temperature variation within the bundle (T(x) 27 C.6 Alternative presentation of the model 27 Bibliography 28 PD CLC/TR 50174-99-1:
14、2015CLC/TR 50174-99-1:2015 - 4 - Foreword This document (CLC/TR 50174-99-1:2015) has been prepared by CLC/TC 215 “Electrotechnical aspects of telecommunication equipment“. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC an
15、d/or CEN shall not be held responsible for identifying any or all such patent rights. PD CLC/TR 50174-99-1:2015 - 5 - CLC/TR 50174-99-1:2015 Introduction EN 50174 series specify the specification, planning and practices applicable to installation of telecommunications cabling. Balanced cabling in ac
16、cordance with EN 50173-1 is increasingly used to provide power as well as telecommunication services to a wide range of terminal equipment. This Technical Report examines the effects of remote powering (i.e. thermal heating) on installed cabling. The components considered are of those specified in E
17、N 50173-1. The components of Category 5 as defined in EN 50173:1995 were not specified in terms of current carrying capacity etc.; they are not supported by this Technical Report. This Technical Report supports recognized application standards for power feeding produced by IEEE (IEEE 802.3at) but is
18、 not restricted to the current feeding specification of that standard. The delivery of POTS, ISDN, PoE and PoEplus using fully energized bundles of up to 100 cables in accordance with EN 50288-X-1 in ventilated pathways is not considered to represent a problem and is not considered in this Technical
19、 Report. In addition, there is no reported evidence of such installations of those remote powering applications producing problems in unventilated conditions. As a result, this Technical Report will only consider such situations if the modelling and subsequent testing of cabling implementations indi
20、cates any cause for concern. PD CLC/TR 50174-99-1:2015CLC/TR 50174-99-1:2015 - 6 - 1 Scope This Technical Report defines requirements and recommendations concerning limits for the application and operation of remote powering using cabling comprising balanced cabling components of Category 5 and abov
21、e as defined in EN 50173-1. This Technical Report also describes: a set of specific implementations which are the basis of a mathematical model for the temperature increases in bundles of cables under remote powering conditions; a matching testing protocol used to provide data for the mathematical m
22、odel; NOTE The testing protocol was established in order to enable comparison of data from different sources in order to support the development of the mathematical model and to develop appropriate planning and installation rules as suggested by different installation conditions. It is not the role
23、of CLC/TC 215 to develop test methods for balanced, or other, cables and the protocol defined in Annex B is not as such a test method. the mathematical model that is employed as the basis for the resulting requirements and recommendations. Safety (electrical safety and protection, optical power, fir
24、e, etc.) and electromagnetic compatibility (EMC) requirements are outside the scope of this Technical Report and are covered by standards and regulations. However, information given in this Technical Report may be of assistance in meeting these standards and regulations. 2 Normative references The f
25、ollowing documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 50173 ser
26、ies, Information technology Generic cabling systems EN 50173-1:2011, Information technology Generic cabling systems Part 1: General requirements EN 50174 series, Information technology Cabling installation EN 50174-2:2009 + A1:2011 + A2:2014, Information technology Cabling installation Part 2: Insta
27、llation planning and practices inside buildings 3 Terms, definitions, abbreviations and symbology 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in EN 50173 series and in EN 50174 series and the following apply. 3.1.1 requirement met by design requiremen
28、t that does not require testing and where conformance may be achieved either by selection of appropriate components and their installation techniques or by conformance of a related parameter PD CLC/TR 50174-99-1:2015 - 7 - CLC/TR 50174-99-1:2015 3.1.2 remote powering supply of electrical power to ap
29、plication specific equipment via balanced cabling 3.2 Abbreviations For the purposes of this document, the abbreviations given in EN 50173 series and the following apply. d.c., DC direct current U/UTP unscreened cable with unscreened balanced cable elements F/UTP foil screened cable with unscreened
30、balanced cable elements S/FTP screened cable with foil screened balanced cable elements 3.3 Symbology For the purposes of this document, the following symbols are used. T total temperature rise between the ambient temperature (or that of the unpowered bundle) and the centre of the bundle T thtempera
31、ture rise between the outer surface and the centre of the bundle T utemperature rise between the ambient temperature (or that of the unpowered bundle) and the outer surface of the bundle i cthe current per conductor (A) n cnumber of conductors per cable carrying remote powering current (i c ) N numb
32、er of cables carrying remote powering current R average d.c. resistance per unit length (/m) of conductors carrying remote powering current thconstant relating to cable construction uconstant relating to installation environment 4 Overview 4.1 General The principal concerns associated with the deliv
33、ery of power are: a) increases in the operating temperature of the cables (exceeding their specified operating temperature); b) damage to connecting hardware contacts where mating and de-mating occurs while the power supply current is flowing; c) the associated increase of channel attenuation/insert
34、ion loss, due to the increased temperature of installed cables, which unless balanced by reduced installed lengths will have a negative effect on channel ACR/PSACR (and may be associated with increased system bit error rates). This Technical Report demonstrates that the thermal impact of remote powe
35、ring is proportional to the number of cables in a bundle (and/or the number of bundles installed in a close proximity to others) and the length over which that installation condition is maintained. Figure 1 is a schematic of the distribution cabling subsystems defined by EN 50173-2 and EN 50173-6 (t
36、ogether with the supporting backbone cabling common to both standards). PD CLC/TR 50174-99-1:2015CLC/TR 50174-99-1:2015 - 8 - EQP BD C FD C C EQP C EQP FD/SD C TO/ SO C C EQP C No. of cables in a bundle or group of bundles Cord CordFixed distribution cabling Fixed backbone cabling Backbone Distribut
37、ionKey BD building distributor of EN 50173-X C connection positions EQP equipment FD floor distributor of EN 50173-2 SD service distributor of EN 50173-6 SO service outlet of EN 50173-6 TO telecommunications outlet of EN 50173-2 Figure 1 Schematic of cabling in accordance with EN 50173 series standa
38、rds showing cable bundle trends The fixed cabling in both the backbone and distribution cabling typically contains multiple bundles of cables as they leave the distributors. In the distribution cabling, the number of bundles in a group and then the number of cables in a bundle reduces towards the ou
39、tlets whereas the backbone bundles tend to be consistent along their length. Connections to equipment at either end is made via cords which tend to be installed as single components or in small groups - and even where larger bundles are created they are accessible and are able to be re-dressed to re
40、duce any identified thermal impact. As a result, the focus of this Technical Report in relation to thermal impact is on the fixed cabling. 4.2 Published standards 4.2.1 ISO/IEC TR 29125:2010 ISO/IEC TR 29125:2010 contains information on temperature rises found at the centre of cable bundles for cabl
41、es of Category 5 and above and for currents of up to 360 mA per conductor. This information was used during the development of IEEE 802.3at to define the limits of power delivered. ISO/IEC TR 29125:2010 suggests that cables of a higher category produce lower temperature increases for a given current
42、 and bundle size. However, all categories of cable currently have the same maximum d.c. resistance specification. This specification is based on the minimum conductor diameter to meet the transmission performances taking into account all the possible designs. Thus, the actual conductor diameter and
43、the d.c. resistance per unit length of the conductor may have more influence than the cable category. ISO/IEC TR 29125:2010 suggests that the temperature rise increases as both the current per pair increases and as the bundle size increases. Based on these assumptions ISO/IEC TR 29125:2010 gives fig
44、ures for increases of temperature according to the current and the bundle size. However, external surfaces of the bundles were in open air, allowing PD CLC/TR 50174-99-1:2015 - 9 - CLC/TR 50174-99-1:2015 cooling by radiation and convection. This is not representative of the full range of pathway sys
45、tems, and when bundles are installed in unventilated cable management systems or in insulating materials, the temperature rise will be higher. 4.2.2 EN 50173-1:2011 EN 50173-1:2011 specifies the d.c. loop resistance requirements of generic cabling channel and links. EN 50173-1:2011 specifies the cur
46、rent carrying capacity requirements of generic cabling channels which are linked to the 10 C temperature rise suggested in ISO/IEC TR 29125:2010 at the centre of a bundle of 100 cables for a current of 300 mA per conductor (all conductors powered). Additionally it is stated that: a) relevant applica
47、tion standards and manufacturers instructions shall be consulted with reference to safety aspects of power feeding; b) care shall be taken when using multi-unit or bundled cables due to the possible rise of temperature within the cabling components that may degrade channel performance. 4.3 Recent de
48、velopments 4.3.1 EN 50173-6 EN 50173-6 specifies generic cabling for distributed building services which is expected to be exploited by a wide range of remote powering solutions including those of IEEE 802.3 and other proprietary products. 4.3.2 IEEE 802.3 IEEE 802.3 is considering the delivery of h
49、igher powers than those specified in IEEE 802.3at. A revision of ISO/IEC TR 29125:2010 is in development at this time. 4.3.3 Other remote powering solutions Installed cabling may be subjected to currents and voltages other than those defined for IEEE 802.3 (both now and in the future). There are many building services such as access control, environmental monitoring and lighting that are designed to operate over the cabling within the scope of this Technical Report. It is common for these services to be the responsibility of different g
