1、National Standard of CanadaCAN/CSA-ISO/IEC 8482-01(ISO/IEC 8482:1993)International Standard ISO/IEC 8482:1993 (second edition, 1993-12-15), has been adopted withoutmodification as CSA Standard CAN/CSA-ISO/IEC 8482-01, which has been approved as a NationalStandard of Canada by the Standards Council o
2、f Canada.ISBN 1-55324-414-1 March 2001Reference numberISO/IEC 8482:1993(E)The Canadian Standards Association, which The Standards Council of Canada is theoperates under the name CSA International coordinating body of the National Standards system, (CSA), under whose auspices this National Standard h
3、as a federation of independent, autonomousbeen produced, was chartered in 1919 and accredited by organizations working towards the furtherthe Standards Council of Canada to the National development and improvement of voluntaryStandards system in 1973. It is a not-for-profit, standardization in the n
4、ational interest.nonstatutory, voluntary membership association The principal objects of the Council are to foster engaged in standards development and certification and promote voluntary standardization as a means activities. of advancing the national economy, benefiting theCSA standards reflect a
5、national consensus of producers health, safety, and welfare of the public, assisting and users including manufacturers, consumers, and protecting the consumer, facilitating domestic retailers, unions and professional organizations, and and international trade, and furthering internationalgovernmenta
6、l agencies. The standards are used widely cooperation in the field of standards.by industry and commerce and often adopted by A National Standard of Canada is a standard whichmunicipal, provincial, and federal governments in their has been approved by the Standards Council ofregulations, particularl
7、y in the fields of health, safety, Canada and one which reflects a reasonablebuilding and construction, and the environment. agreement among the views of a number of capableIndividuals, companies, and associations across Canada individuals whose collective interests provide to theindicate their supp
8、ort for CSAs standards development greatest practicable extent a balance ofby volunteering their time and skills to CSA Committee representation of producers, users, consumers, andwork and supporting the Associations objectives others with relevant interests, as may be appropriatethrough sustaining
9、memberships. The more than 7000 to the subject in hand. It normally is a standardcommittee volunteers and the 2000 sustaining which is capable of making a significant and timelymemberships together form CSAs total membership contribution to the national interest.from which its Directors are chosen.
10、Sustaining Approval of a standard as a National Standard ofmemberships represent a major source of income for Canada indicates that a standard conforms to theCSAs standards development activities. criteria and procedures established by the StandardsThe Association offers certification and testing se
11、rvices Council of Canada. Approval does not refer to thein support of and as an extension to its standards technical content of the standard; this remains thedevelopment activities. To ensure the integrity of its continuing responsibility of the accreditedcertification process, the Association regul
12、arly and standards-development organization.continually audits and inspects products that bear the Those who have a need to apply standards areCSA Mark. encouraged to use National Standards of CanadaIn addition to its head office and laboratory complex in whenever practicable. These standards are su
13、bject Toronto, CSA has regional branch offices in major centres to periodic review; therefore, users are cautioned across Canada and inspection and testing agencies in to obtain the latest edition from the organizationeight countries. Since 1919, the Association has preparing the standard.developed
14、the necessary expertise to meet its corporate The responsibility for approving National Standards mission: CSA is an independent service organization of Canada rests with thewhose mission is to provide an open and effective forum Standards Council of Canadafor activities facilitating the exchange of
15、 goods and 270 Albert Street, Suite 200services through the use of standards, certification and Ottawa, Ontario, K1P 6N7related services to meet national and international needs. CanadaFor further information on CSA services, write toCSA International178 Rexdale BoulevardToronto, Ontario, M9W 1R3Can
16、adaAlthough the intended primary application of this Standard is stated in its Scope, it is importantto note that it remains the responsibility of the users to judge its suitability for their particular purpose.Registered trade-mark of Canadian Standards AssociationInformation technology Telecommuni
17、cations and informationCAN/CSA-ISO/IEC 8482-01 exchange between systems Twisted pair multipoint interconnectionsMarch 2001 CSA/1CAN/CSA-ISO/IEC 8482-01Information technology Telecommunications andinformation exchange betweensystems Twisted pair multipointinterconnectionsCSA PrefaceStandards developm
18、ent within the Information Technology sector is harmonized with internationalstandards development. Through the CSA Technical Committee on Information Technology (TCIT),Canadians serve as the Canadian Advisory Committee (CAC) on ISO/IEC Joint Technical Committee 1 onInformation Technology (ISO/IEC J
19、TC1) for the Standards Council of Canada (SCC), the ISO memberbody for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of theInternational Telecommunication Union (ITU), Canada participates in the International Telegraph andTelephone Consultative Committee (ITU-T)
20、.This International Standard was reviewed by the CSA TCIT under the jurisdiction of the StrategicSteering Committee on Information Technology and deemed acceptable for use in Canada. (Acommittee membership list is available on request from the CSA Project Manager.) From time to time,ISO/IEC may publ
21、ish addenda, corrigenda, etc. The CSA TCIT will review these documents for approvaland publication. For a listing, refer to the CSA Information Products catalogue or CSA Info Update orcontact a CSA Sales representative. This Standard has been formally approved, without modification, bythese Committe
22、es and has been approved as a National Standard of Canada by the Standards Council ofCanada.March 2001 CSA International 2001All rights reserved. No part of this publication may be reproduced in any form whatsoever without the prior permission ofthe publisher. ISO/IEC material is reprinted with perm
23、ission. Inquiries regarding this National Standard of Canada shouldbe addressed to CSA International, 178 Rexdale Boulevard, Toronto, Ontario, M9W 1R3.INTERNATIONAL STANDARD ISO/IEC 8482 Second edition 19934 2-l 5 Information technology - Telecommunications and information exchange between Systems -
24、 Twisted pair multipoint interconnections Technologies de Iinforma tion - T6kommunications et khange dinformations entre syst - a binar-y and bi-directional Signal transfer of the interconnected endpoint Systems; - the electrical and mechanical design of the endpoint System branch cables and the com
25、mon trunk cable, which may be up to 1 200 m in length; - the component measurements of the integrated circuit type generators and receivers within the endpoint Systems; - the applicable data signalling rate up to 12,5 Mbit/s. 12 The defined electrical component charac- teristics and measurements are
26、 in close conformance with the twisted pair Point-to-Point characteristics given in ITU-T Recommendation V.11. 13 This International Standard does not de- scribe a complete physical interface and has no functional interface characteristics, such as - number of interchange data and control circuits;
27、- type, size and pin allocation of the endpoint System and branch trunk cable connectors; - data and control Signal encoding; - time relations between Signals on the interchange circuits; - mode of synchronous or asynchronous trans- mission; - Signal quality for transmission and reception. 14 . This
28、 International Standard does not specify special environmental conditions, such as galvanic isolation, electromagnetic interference (EMI), radio frequency interference (RFI), and human safety. This may form the subject of a future amendment. 15 . This International Standard is primarily a component
29、specif icat ion. lt is not sufficiently specified for satisfactory interoperation in all possible configurations. lt is the responsibility of implementors to ensure that their intended configuration will allow satisfactory interoperation. 16 This International Standard may be com- bined with any app
30、ropriate set of functional and additional environmental characteristics so as to meet the practical data transmission requirements in the field of local or wide area networks. 2 Normative reference The following ITU-T Recommendation contains certain provisions which, through reference in this text,
31、constitutes provisions of this International Standard. At the time of publication, the edition indicated was valid. All CCITT Recommendations and International Standards are subject to revision, and Parties to agreements based on this International Standard are encouraged to investigate the possibil
32、ity of applying the most recent edition of the recommendation indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. The ITU-T Secretariat maintains a list of currently valid ITU-T Recommendations. 1 ISO/IEC 8482:1993(E) ITU-T Recommendation V.11 :1988
33、, Electrical characteristics for balanced double-curren t inter- Change circuits for general use with integrated circuit equipment in the field of data communications. 3.6 differential mode voltage: The vector differente of the voltages between each conductor of a balanced interchange circuit and gr
34、ound or other stated voltage reference. NOTE - The differential mode voltage is commonly referred to as the transverse mode voltage. 3 Definitions For the purposes of this International Standard the following definitions apply: 3.1 balanced interchange circuit: An interchange circuit which uses two
35、conductors and the differential mode voltage for transmitting Signals. 3.2 common mode ejection ratio (CMRR ): For balanced interchange circuits, the ratio of an applied common mode voltage, Isis the short circuit current, in amperes; Z, is the cable characteristics impedance, in Ohms. With a 250 mA
36、 peak current limit, this voltage will equal about 15 V. If four, or more receivers are ON (circuit current up to 500 mA) and the unlikely event occurs where two generators are turned OFF such that the current interruptions concur on the circuit, the differential voltage could rise to a larger value
37、. The designer is cautioned to consider this possibility in the System design. The requirements specified in clause 10 are designed to protect when only one such event occurs. 17 ISOJIEC 8482:1993(E) Annex B (informative) Guidance on a.c. loading measurement The a.c. loading on the multipoint medium
38、 caused by the connection of the endpoint Systems determines the transmission Performance. This loading is the most part is dependent on the Parameters of the application such as, type of encoding, signalling rate and the characteristics of the branch cable. Therefore the following measurements are
39、provided for general guidance only and may have to be modified to be appropriate for measurement in accordance with the complete interface and Signal quality Standards (see also clause A.l of annex A). Bl . Reflection attenuation (sec figure B.l) The reflection attenuation of a connected endpoint Sy
40、stem should not be less than 20 dB for frequency range corresponding to the main transmission spectrum. The measurement is made at the disconnected branch/trunk cable connector of an endpoint System using a parallel test resistor of 120 s1. The recommended measurement configuration is shown in figur
41、e B.l. During the test, any generator involved is in an inactive state. B2 . Receiving Signal distortion The receiving Signal distortion measured at the interconnected branch/trunk cable connector of an endpoint System should not exceed 25 % for mark/space reversals at the application signalling rat
42、e. NOTE - In the case of twisted pair transmission medium it is assumed that the Pattern dependent distortion is not very far outside the range of the markkpace reversals measurement. aR = 20 log =$ (in dB) Figure B.1 - Reflection attenuation measurement This page intentionally left blank This page
43、intentionally left blank This page intentionally left blank ISO/IEC 8482:1993(E) UDC 681.327.8:621.316.5 Descriptors: data processing, information interchange, telecommunications, data transmission, network interconnection, data communication equipment. Price based on 18 pages A not-for-profit private sector organization Organisme sans but lucratif du secteur prive178 Rexdale Boulevard 178, boulevard RexdaleToronto, Ontario, Canada M9W 1R31 800 463.6727+ 1 416 747.4044www.csa-international.orgISBN 1-55324-414-1
