1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T K.59 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (12/2015) SERIES K: PROTECTION AGAINST INTERFERENCE Electromagnetic compatibility, resistibility and safety requirements and procedures for connection to unbundled cables
2、 Recommendation ITU-T K.59 Rec. ITU-T K.59 (12/2015) i Recommendation ITU-T K.59 Electromagnetic compatibility, resistibility and safety requirements and procedures for connection to unbundled cables Summary Recommendation ITU-T K.59 aims to establish minimum requirements, procedures and management
3、rules to be followed in order to take into account electromagnetic compatibility (EMC), resistibility and safety aspects for connection to unbundled cables. With the liberalization of telecommunications, many services are provided by several operators on the same cable. This means that operators, wh
4、o are not the owner of the cable, may use several pairs in the cable for various services. In this situation, EMC resistibility and safety problems may occur in the cable. Therefore, it is necessary to establish proper requirements and procedures from an EMC point of view. History Edition Recommenda
5、tion Approval Study Group Unique ID* 1.0 ITU-T K.59 2003-07-29 5 11.1002/1000/6503 2.0 ITU-T K.59 2015-12-14 5 11.1002/1000/12687 * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:
6、/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T K.59 (12/2015) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Secto
7、r (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every
8、four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview,
9、the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary
10、. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the ne
11、gative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the
12、use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendati
13、on, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/
14、www.itu.int/ITU-T/ipr/. ITU 2016 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T K.59 (12/2015) iii Table of Contents Page 1 Scope . 1 2 References . 1 3 Definitions 2 3.1 Terms defined elsewhere 2 3
15、.2 Terms defined in this Recommendation . 2 4 Abbreviations and acronyms 2 5 Conventions 3 6 Configuration and problems in multiple operator environment . 3 7 Issues to be considered . 3 8 Requirements 4 8.1 Safety 4 8.2 Resistibility . 4 8.3 EMC . 5 8.4 Mutual interference 5 9 Procedures for counte
16、rmeasures . 5 9.1 Safety 5 9.2 Resistibility . 6 9.3 Emission and immunity 6 9.4 Mutual interference 7 10 Guidance on responsibility . 7 10.1 Priority of existing services 8 10.2 Guarantee of minimum quality . 8 iv Rec. ITU-T K.59 (12/2015) Introduction With the liberalization of telecommunications,
17、 many services are provided by several operators on the same cable. This means that operators, who are not the owner of the cable, may use several pairs in the cable for various services. In this situation, electromagnetic compatibility (EMC), resistibility and safety problems may occur in the cable
18、. Therefore, it is necessary to establish necessary requirements and procedures from an EMC point of view. This Recommendation describes minimum requirements, procedures and management rules to be followed in order to take into account EMC, resistibility and safety aspects for unbundled cables. Rec.
19、 ITU-T K.59 (12/2015) 1 Recommendation ITU-T K.59 Electromagnetic compatibility, resistibility and safety requirements and procedures for connection to unbundled cables 1 Scope The purpose of this Recommendation is to ensure safe and problem-free operation for connections to unbundled cables. This R
20、ecommendation is applied when equipment or a system is connected to unbundled cables. Minimum requirements are given in this Recommendation in order to ensure safe and problem-free operation and to reduce trouble related to electromagnetic compatibility (EMC), safety and resistibility. The main aspe
21、cts are safety for humans and equipment, emission and immunity, resistibility of equipment against overvoltage and overcurrent and mutual interference. Requirements that are not related to EMC, safety and resistibility, are outside the scope of this Recommendation. 2 References The following ITU-T R
22、ecommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation ar
23、e therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as
24、a stand-alone document, the status of a Recommendation. ITU-T K.10 Recommendation ITU-T K.10 (1996), Low frequency interference due to unbalance about earth of telecommunication equipment. ITU-T K.37 Recommendation ITU-T K.37 (1999), Low and high frequency EMC mitigation techniques for telecommunica
25、tion installations and systems Basic EMC Recommendation. ITU-T K.43 Recommendation ITU-T K.43 (2009), Immunity requirements for telecommunication equipment. ITU-T K.44 Recommendation ITU-T K.44 (2012), Resistibility tests for telecommunication equipment exposed to overvoltages and overcurrents Basic
26、 Recommendation. ITU-T K.46 Recommendation ITU-T K.46 (2012), Protection of telecommunication lines using metallic symmetric conductors against lightning-induced surges. ITU-T K.47 Recommendation ITU-T K.47 (2012), Protection of telecommunication lines against direct lightning flashes. ITU-T K.48 Re
27、commendation ITU-T K.48 (2006), EMC requirements for telecommunication equipment Product family Recommendation. ITU-T K.50 Recommendation ITU-T K.50 (2000), Safe limits of operating voltages and currents for telecommunication systems powered over the network. ITU-T K.51 Recommendation ITU-T K.51 (20
28、09), Safety criteria for telecommunication equipment. ITU-T K.54 Recommendation ITU-T K.54 (2004), Conducted immunity test method and level at fundamental power frequencies. 2 Rec. ITU-T K.59 (12/2015) ITU-T K.60 Recommendation ITU-T K.60 (2015), Emission levels and test methods for wireline telecom
29、munication networks to minimize electromagnetic disturbance of radio services. ITU-T K.63 Recommendation ITU-T K.63 (2004), Maintaining the suitability of production telecommunications equipment to its intended electromagnetic environment. ITU-T K.66 Recommendation ITU-T K.66 (2011), Protection of c
30、ustomer premises from overvoltages. ITU-T G.961 Recommendation ITU-T G.961 (1993), Digital transmission system on metallic local lines for ISDN basic rate access. ITU-T G.992.1 Recommendation ITU-T G.992.1 (1999), Asymmetric digital subscriber line (ADSL) transceivers. ITU-T G.993.2 Recommendation I
31、TU-T G.993.2 (2015), Very high speed digital subscriber line transceivers 2 (VDSL2). ITU-T L.19 Recommendation ITU-T L.19 (2010), Multi-pair copper network cable supporting shared multiple services such as POTS, ISDN and xDSL. IEC 60950-1 IEC 60950-1 (2005), Information technology equipment Safety P
32、art 1: General requirements. IEC 60950-21 IEC 60950-21 (2003), Information technology equipment Safety Part 21: Remote Power Feeding. 3 Definitions 3.1 Terms defined elsewhere None. 3.2 Terms defined in this Recommendation This Recommendation defines the following term: 3.2.1 unbundling: Condition w
33、here multiple services, provided by more than one operator, share the same metallic cable. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: ADSL Asymmetric Digital Subscriber Line ANFP Access Network Frequency Plan DSL Digital Subscriber Line EMC Electr
34、omagnetic Compatibility ISDN Integrated Services Digital Networks LCL Longitudinal Conversion Loss POTS Plain Old Telephone Service SPD Surge Protection Device TCL Transverse Conversion Loss VDSL Very high-speed Digital Subscriber Line Rec. ITU-T K.59 (12/2015) 3 xDSL x-type Digital Subscriber Line
35、5 Conventions None. 6 Configuration and problems in multiple operator environment A configuration and some problems related to unbundling are shown in Figure 1. For unbundling, multiple operators use the same metallic cable for their services. Therefore, they may produce human hazard, emission, or p
36、rotection problems because their installation characteristics, such as operating voltage, transmission signal and protocol, are different. Furthermore, in the cable, there is also a possibility of these services causing mutual interference. In these situations, the reliability and safety of equipmen
37、t may be ensured by unifying equipment specifications, or by testing equipment installed in a telecommunication centre, when the equipment is owned by a single operator. However, in a multiple operator environment, reliability and safety are difficult to ensure with the usual procedures applied for
38、a single operator environment because different operators may have different equipment specifications. Therefore, necessary procedures and minimum requirements for equipment or systems related to EMC, resistibility and safety should be established to avoid malfunctions or damage arising from electro
39、magnetic interference and to ensure the safety of service personnel and customers. Figure 1 Configuration and problems for unbundled cable 7 Issues to be considered 1) Safety: Service personnel may face hazards when an operating voltage, a voltage induced from a power or railway line, or a leakage c
40、urrent from centre equipment, terminal equipment, or a repeater does not comply with existing safety standards. 2) Unintentional emission: If a radiated unintentional disturbance is emitted from a cable into the surrounding area, it is necessary to determine its source. Collaboration between operato
41、rs will be necessary to solve this problem. 3) Protection coordination: In the case where protection is not coordinated between operators, overvoltage or overcurrent may be applied to equipment and equipment may be damaged. To overcome this problem, protection coordination should be established betw
42、een operators. 4 Rec. ITU-T K.59 (12/2015) 4) Mutual interference: Mutual interference in a cable degrades quality because many types of signals are transmitted. Crosstalk in the normal mode signal should be taken into account in the case of unbundling. 8 Requirements The following arrangements are
43、required to ensure safe and problem-free operation for connection to unbundled cable. Existing Recommendations are referred to in order to avoid duplication. Where existing Recommendations cannot be applied, the following requirements are applicable. If additional requirements, or enhanced requireme
44、nts, are required in national or other local regulations, operators involved should investigate and determine the best way to comply with them. In some instances, special measures may need to be agreed between operators. 8.1 Safety Safety requirements related to operating voltage and induced voltage
45、 shall comply with ITU-T K.50, ITU-T K.51, ITU-T K.54, IEC 60950-1 and IEC 60950-21. In the case of joint use of cable, it is necessary to specify the limits and countermeasures for human and equipment safety between multiple operators. Furthermore, operators should warn service personnel, by labell
46、ing or marking, to take precautions when working on the cable. In cases of higher voltages or currents appearing and in agreement with national limits for it, such as earth potential rise, cautionary measures, such as labelling or marking, should be added at appropriate points to ensure human safety
47、 is maintained. 8.1.1 Safety requirements for equipment powered over telecommunication cable Systems powered over the networks shall comply with ITU-T K.50 and ITU-T K.51 for safety. An operator who owns such systems should inform other operators that higher voltage or current may appear on the cabl
48、e. 8.1.2 Safety for induction from power lines and railways Limits against induced voltage from power lines or from electrical railways shall comply with ITU-T K.54. Information about induction on cable should be shared among operators in order to ensure safety of service personnel or equipment. 8.2
49、 Resistibility 8.2.1 Basic requirements Equipment connected to an unbundled cable shall comply with appropriate resistibility requirements relevant to each environment. When higher resistibility is required, operators may choose the enhanced level of ITU-T K-series resistibility Recommendations. Guidance on choosing the enhanced level is given in clause 5 of ITU-T K.44. If a requirement does not meet or does not comply with necessary protection levels defined in each country, operators involved should d
