1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T K.54TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (12/2004) SERIES K: PROTECTION AGAINST INTERFERENCE Conducted immunity test method and level at fundamental power frequencies ITU-T Recommendation K.54 ITU-T Rec. K.54 (12/2004) i ITU-T Recommendation K.
2、54 Conducted immunity test method and level at fundamental power frequencies Summary This Recommendation presents the simplified immunity test method, the test procedure and the immunity test level for equipment with telecommunication ports connected to external telecommunication lines against condu
3、cted disturbances which can be induced on telecommunication lines by a.c. power or electrified railway lines under normal operating conditions.Source ITU-T Recommendation K.54 was approved on 14 December 2004 by ITU-T Study Group 5 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T R
4、ec. K.54 (12/2004) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and ta
5、riff 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 four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recom
6、mendations 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, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recomme
7、ndation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperabil
8、ity 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 negative equivalents are used to express requirements. The use of such words does not suggest that compl
9、iance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity
10、 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 Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required
11、 to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2005 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without
12、 the prior written permission of ITU. ITU-T Rec. K.54 (12/2004) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 4 Immunity test conditions 2 5 Performance criterion . 2 6 Test method and procedure. 2 iv ITU-T Rec. K.54 (12/2004) Introduction Disturbances at fundamental power frequencies
13、(16 , 50 or 60 Hz) can be induced on telecommunication lines by a.c. power and electrified railway lines under normal operating conditions. Therefore, there is a need to define immunity requirements at these frequencies of equipment with telecommunication ports connected to external telecommunicatio
14、n lines. This Recommendation presents the immunity test method, the test procedure and the immunity test levels for telecommunication equipment. Background information on the test set-up is given in the “Handbook on interference measuring techniques“ 1. Other coupling networks are possible. (See 1.)
15、 ITU-T Rec. K.54 (12/2004) 1 ITU-T Recommendation K.54 Conducted immunity test method and level at fundamental power frequencies 1 Scope This Recommendation refers to long-term (i.e., longer than 1 second) voltages induced by a.c. power or electrified railway lines on telecommunication lines. The Re
16、commendation defines: the immunity level, which a telecommunication equipment shall comply to; the test method and procedure, which shall be used to verify the immunity level. The tests are applicable to telecommunication ports connected to external metallic telecommu-nication lines. 2 References Th
17、e following ITU-T Recommendations 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 thi
18、s Recommendation are 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 do
19、es not give it, as a stand-alone document, the status of a Recommendation. 1 ITU-T Handbook (2002), Interference measuring techniques, Part A. 2 ITU-T (1989) Directives concerning the protection of telecommunication lines against harmful effects from electric power and electrified railway lines, Vol
20、ume VI: Danger and disturbance. 3 ITU-T Recommendation K.43 (2003), Immunity requirements for telecommunication equipment. 3 Definitions This Recommendation defines the following terms: 3.1 common mode induced disturbances: Voltage induced on telecommunication line by an a.c. power or electrified ra
21、ilway line under normal operating conditions between the equipment telecommunication port and a reference earth. 3.2 test frequency: The test frequency is the fundamental power frequency used in the area, where the telecommunication plant is located, i.e., 16 , 50 or 60 Hz. 3.3 external telecommunic
22、ation line: Telecommunication line which leaves a telecommunica-tion centre or shelter or customer building. 3.4 reference earth: A point in the soil, whose electrical potential is presumed to be zero. This concept is used both in the calculation and measurement of voltages, considered as difference
23、 of the potential induced in the telecommunication plant and the potential of the soil. Other definitions are found in ITU-T Rec. K.43 3. 2 ITU-T Rec. K.54 (12/2004) 4 Immunity test conditions The immunity level of conducted long-term disturbances at fundamental power frequencies is the r.m.s. level
24、 of the common mode voltage between telecommunication port and earth. The immunity level shall be 60 V. The test duration shall not be less than 1 minute and not exceed 15 minutes. 5 Performance criterion During the test, the Equipment Under Test (EUT) shall meet its performance requirements. 6 Test
25、 method and procedure A simplified test circuit is shown in Figure 1 for symmetrical pair ports (unshielded or shielded cable) whereas it is under study for coaxial pairs. Figure 1/K.54 Test circuit for shielded and unshielded cables Switch S in position 1, when the associated equipment has an imped
26、ance to earth greater than 30 k. Switch S in position 2, when the associated equipment has an impedance to earth less than 30 k. In Figure 1, the open circuit voltage of the test generator, Uac, is the required immunity level. When the common mode impedance of the EUT is low, the common mode voltage
27、 occurring at the port of the EUT is significantly lower than the voltage of the test generator. The earthing connections of the EUT shall be implemented according to the real installation conditions. If the Auxiliary Equipment (AE) has a lower immunity level than that required of the EUT, it is nec
28、essary to use a decoupling network to isolate the AE from the common mode disturbance. For this purpose, it is possible to use common mode transformers on the telecommunication lines. In ITU-T Rec. K.54 (12/2004) 3 this case, if the EUT is powered by a remote feeding circuit through the telecommunic
29、ation line, the d.c. voltage generator on the line shall be used to supply the EUT. The EUT test conditions (operating state, earthing connections, wiring, etc.) should be as close as possible to the real installation conditions. If the EUT is designed to be mounted in a rack or cabinet, it should b
30、e tested in this configuration. The signal or control ports shall be correctly terminated either by auxiliary equipment necessary to exercise the ports or in their nominal impedance. Auxiliary equipment may be used to simulate the functional termination of the ports. Special additional equipment, e.
31、g., a traffic simulator, and/or software, line attenuator, line simulator, may be used to simulate the operating conditions. NOTE The operation of the test simulator shall be verified for correct operation before applying the disturbing voltage. In Figure 1, the following values of the components sh
32、ould be used: Rg= 50 R = 150 C1= 120 nF ZS= 100 C2= 10 F These values take into account the worst-case conditions concerning line lengths, number of pairs and centre of exposure. The inductance L of the coupling network for differential mode should provide a high impedance compared with the differen
33、tial mode impedance of the EUT. Printed in Switzerland Geneva, 2005 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecomm
34、unication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection a
35、gainst interference Series L Construction, installation and protection of cables and other elements of outside plant Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specific
36、ations of measuring equipment Series P Telephone transmission quality, telephone installations, local line networks Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects and next-generation networks Series Z Languages and general software aspects for telecommunication systems
