IEC 60794 1 1 Edition 4 0 201 5 1 1 INTERNATIONAL STANDARD Optical fibre cables – Part 1 1 Generic specification – General IE C 6 0 7 9 4 1 1 2 0 1 5 1 1 (e n ) ® colour inside Copyright International[.]
I E C 60 4-1 -1 ® Edition 4.0 201 5-1 I N TE RN ATI ON AL S TAN D ARD colour i n sid e Opti cal fi bre cabl e s – IEC 60794-1 -1 :201 5-1 (en) P art -1 : G en eri c s peci fi cati on – G en eral T H I S P U B L I C AT I O N I S C O P YRI G H T P RO T E C T E D C o p yri g h t © I E C , G e n e v a , S wi tz e rl a n d All rights reserved Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or IEC's member National Committee in the country of the requester If you have any questions about I EC copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or your local I EC member National Committee for further information IEC Central Office 3, rue de Varembé CH-1 21 Geneva 20 Switzerland Tel.: +41 22 91 02 1 Fax: +41 22 91 03 00 info@iec.ch www.iec.ch Ab ou t th e I E C The I nternational Electrotechnical Commission (I EC) is the leading global organization that prepares and publishes I nternational Standards for all electrical, electronic and related technologies Ab o u t I E C p u b l i ca ti o n s The technical content of IEC publications is kept under constant review by the IEC Please make sure that you have the latest edition, a corrigenda or an amendment might have been published I E C Catal og u e - webstore i ec ch /catal og u e The stand-alone application for consulting the entire bibliographical information on IEC International Standards, Technical Specifications, Technical Reports and other documents Available for PC, Mac OS, Android Tablets and iPad I E C pu bl i cati on s s earch - www i ec ch /search pu b The advanced search enables to find IEC publications by a variety of criteria (reference number, text, technical committee,…) It also gives information on projects, replaced and withdrawn publications E l ectroped i a - www el ectroped i a org The world's leading online dictionary of electronic and electrical terms containing more than 30 000 terms and definitions in English and French, with equivalent terms in additional languages Also known as the International Electrotechnical Vocabulary (IEV) online I E C G l os sary - s td i ec ch /g l oss ary More than 60 000 electrotechnical terminology entries in English and French extracted from the Terms and Definitions clause of IEC publications issued since 2002 Some entries have been collected from earlier publications of IEC TC 37, 77, 86 and CISPR I E C J u st Pu bl i s h ed - webstore i ec ch /j u stpu bl i sh ed Stay up to date on all new IEC publications Just Published details all new publications released Available online and also once a month by email I E C C u stom er S ervi ce C en tre - webstore i ec ch /csc If you wish to give us your feedback on this publication or need further assistance, please contact the Customer Service Centre: csc@iec.ch I E C 60 4-1 -1 ® Edition 4.0 201 5-1 I N TE RN ATI ON AL S TAN D ARD colour i n sid e Opti cal fi bre cabl es – P art -1 : G e n eri c s peci fi cati on – G en e ral INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 33.1 80.1 ISBN 978-2-8322-3002-2 Warn i n g ! M ake su re th a t you obtai n ed th i s pu bl i cati on from an au th ori zed d i s tri bu tor ® Registered trademark of the International Electrotechnical Commission –2– I EC 60794-1 -1 : 201 © I EC 201 CONTENTS FOREWORD Scope Norm ative references Terms and definitions Graphical sym bols and abbreviations Optical fibre cables Materials Optical fibre General Attenuation coefficient Attenuation uniformity – Attenuation discontinuities Cable cut-off wavelength Fibre colouring Polarization mode dispersion (PMD) Electrical conductors Other m aterials Environm ental requirem ents Cable construction General Colour coding Overview 2 Unit colour coding Sheath colour coding Measuring m ethods General Measuring methods for dim ensions Measuring m ethods for mechanical characteristics Measuring m ethods for electrical characteristics Measuring methods for transmission and optical characteristics Measuring m ethods for environm ental characteristics Measuring methods for cable element characterisation Related Technical Reports Annex A (informative) Guidelines for specific defined applications and cabled fibre perform ance A General A Cabled fibre attenuation requirem ents A Cabled fibre bandwidth requirements A Type testing at 625 nm 20 Annex B (informative) Guidelines for qualification sam pling 21 B General 21 B Fibre selection for cable testing 21 B Pass/fail criteria 21 Bibliograph y 23 Table – Measuring m ethods for dim ensions I EC 60794-1 -1 : 201 © I EC 201 –3– Table – Measuring methods for electrical characteristics Table – Measuring m ethods for transmission and optical characteristics of cabled optical fibres Table A – Maximum cabled fibre attenuation coefficient (dB/km ), as given by I TU -T Table A – Category A1 m ultimode fibre maxim um cable attenuation coefficient (dB/km) Table A – Single-mode m axim um cable attenuation coefficient (dB/km) Table A – Category A1 m ultimode cabled fibre bandwidth (MH z km ) 20 Table A – Guidance values for 625 nm type test acceptance criteria 20 ∙ –4– I EC 60794-1 -1 : 201 © I EC 201 INTERNATI ONAL ELECTROTECHNI CAL COMMISSI ON O P T I C AL F I B RE C AB L E S – P a rt -1 : G e n e ri c s p e c i fi c a ti o n – G e n e l FOREWORD ) The I nternati on al Electrotechni cal Comm ission (I EC) is a worl d wid e organization for stan dardization com prisin g all n ation al el ectrotechnical comm ittees (I EC National Comm ittees) The object of I EC is to prom ote internati onal co-operation on all q uestions concerni ng stand ardi zati on in the el ectrical an d electronic fi elds To this en d and in additi on to other acti vities, I EC pu blish es I nternational Stan dards, Techn ical Specificati ons, Technical Reports, Publicl y Avail abl e Specificati ons (PAS) an d Gu ides (h ereafter referred to as “I EC Publication(s)”) Th ei r preparation is entrusted to tech nical comm ittees; any I EC N ational Comm ittee interested in the subj ect dealt with m ay partici pate in this preparatory work I nternational, governm ental an d n on governm ental organ izations l iaising with th e I EC also participate i n this preparation I EC collaborates closel y with the I nternational Organi zation for Stand ardization (I SO) in accordance with ditions determ ined by agreem ent between th e two organi zati ons 2) The form al decisions or ag reem ents of I EC on tech nical m atters express, as n early as possible, an i nternati onal consensus of opi nion on the rel evant subjects since each technical com m ittee has representati on from all interested I EC N ational Com m ittees 3) I EC Publications have the form of recom m endations for intern ational use an d are accepted by I EC National Com m ittees in that sense While all reasonable efforts are m ade to ensure that th e tech nical content of I EC Publications is accu rate, I EC cann ot be h eld responsi ble for th e way in which th ey are used or for an y m isinterpretation by an y en d u ser 4) I n order to prom ote intern ational u niform ity, I EC National Com m ittees und ertake to apply I EC Publications transparentl y to the m axim um extent possible i n their national an d regi on al publicati ons Any d ivergence between an y I EC Publication and the correspondi ng national or regi on al publicati on sh all be clearl y in dicated in the latter 5) I EC itself d oes n ot provi de an y attestation of conform ity I n depend ent certificati on bodies provi de conform ity assessm ent services and, in som e areas, access to I EC m arks of conform ity I EC is not responsi ble for an y services carri ed out by ind ependent certification bodi es 6) All users shou ld ensure that th ey h ave the l atest editi on of thi s publicati on 7) No liability shall attach to I EC or its directors, em ployees, servants or ag ents inclu din g in divi du al experts an d m em bers of its tech nical com m ittees and I EC Nati on al Com m ittees for any person al i nju ry, property d am age or other dam age of any n ature whatsoever, wheth er di rect or indirect, or for costs (includ i ng leg al fees) and expenses arisi ng out of the publ ication, use of, or relian ce upon, this I EC Publicati on or any other I EC Publications 8) Attention is drawn to th e N orm ative references cited in th is publ ication Use of the referenced publ ications is indispensable for the correct applicati on of this publication 9) Attention is drawn to the possibility that som e of the elem ents of this I EC Publication m ay be the su bject of patent rig hts I EC shall not be held responsibl e for identifyi ng any or all such patent ri ghts I nternational Standard I EC 60794-1 -1 has been prepared by subcom mittee 86A: Fibres and cables, of I EC technical committee 86: Fibre optics This fourth edition cancels and replaces the third edition, published in 201 This edition constitutes a technical revision This edition includes the following significant technical changes with respect to the previous edition: a) the expansion of the definitions, graphical symbols, terminology and abbreviations content, with the aim of making this standard the default and reference for all others in the I EC 60794-x series; b) the inclusion of updated and expanded optical fibre, attenuation and bandwidth sections, with the aim of m aking this standard the default and reference for all others in the I EC 60794-x series I EC 60794-1 -1 : 201 © I EC 201 –5– The text of this standard is based on the following documents: CDV Report on votin g 86A/1 651 /CDV 86A/1 667/RVC Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table A list of all parts in the I EC 60794 series, published under the general title cables, can be found on the I EC website Optical fibre This publication has been drafted in accordance with the I SO/I EC Directives, Part The comm ittee has decided that the contents of this publication will remain unchanged until the stability date indicated on the I EC website under "http: //webstore.iec.ch" in the data related to the specific publication At this date, the publication will be • • • • reconfirmed, withdrawn, replaced by a revised edition, or amended A bilingual version of this publication m ay be issued at a later date I M P O RT AN T th at it – Th e co n ta i n s u n d e rs t a n d i n g c o l o u r p ri n t e r of ' co l ou r c o l o u rs i ts i n si de' wh i ch c o n te n ts l og o a re U s e rs on th e cover c o n s i d e re d sh ou l d p ag e to t h e re fo re of th i s be p ri n t p u b l i cati on u s e fu l th i s fo r i n d i c ate s th e d ocu m e n t c o rre c t u si n g a –6– I EC 60794-1 -1 : 201 © I EC 201 O P T I C AL F I B RE C AB L E S – P a rt -1 : G e n e ri c s p e c i fi c a ti o n – G e n e l S cop e This part of I EC 60794 applies to optical fibre cables for use with com munication equipm ent and devices employing similar techniques and to cables having a com bination of both optical fibres and electrical conductors The object of this standard is to establish uniform generic requirem ents for the geom etrical, transm ission, m aterial, m echanical, ageing (environmental exposure), clim atic and electrical properties of optical fibre cables and cable elements, where appropriate N o rm a t i ve re fe re n c e s The following docum ents, in whole or in part, are normativel y referenced in this docum ent and are indispensable for its application For dated references, onl y the edition cited applies For undated references, the latest edition of the referenced docum ent (including an y amendments) applies I EC 601 89-1 , Low-frequency cables and wires with PVC insulation and PVC sheath – Part 1: General test and measuring methods I EC 60304, Standard colours for insulation for low-frequency cables and wires I EC 60793-1 -21 , Optical Fibres Part 1-21: Measurement methods and test procedures – I EC 60793-1 -40, Optical fibres – Part 1-40: Measurement methods and test procedures – I EC 60793-1 -44, Optical fibres – Part 1-44: Measurement methods and test procedures – Cut- Coating geometry Attenuation off wavelength Optical fibres – Part 1-46: Measurement methods and test procedures – Monitoring of changes in optical transmittance IEC 60793-1 -46, Optical fibres – Part 1-48: Measurement methods and test procedures – Polarization mode dispersion IEC 60793-1 -48, IEC 60793-2, Optical fibres – Part 2: Product specifications – General I EC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for class B single-mode fibres Optical fibre cables – Part 1-21: Generic specification – Basic optical cable test procedures – Mechanical tests methods IEC 60794-1 -21 , Optical fibre cables – Part 1-22: Generic specification – Basic optical cable test procedures – Environmental tests methods IEC 60794-1 -22, I EC 60794-1 -1 : 201 © I EC 201 –7– IEC 6081 -201 , Electric and optical fibre cables – Test methods for non-metallic materials – Part 201 : General tests – Measurement of insulation thickness IEC 6081 -202, Electric and optical fibre cables – Test methods for non-metallic materials – Part 202: General tests – Measurement of thickness of non-metallic sheath IEC 6081 -203, Electric and optical fibre cables – Test methods for non-metallic materials – Part 203: General tests – Measurement of overall dimensions I EC TR 61 931 , Fibre optic – Terminology I SO 4001 , Environmental management systems – Requirements with guidance for use I SO 4064-1 , Greenhouse gases – Part : Specification with guidance at the organization level for quantification and reporting of greenhouse gas emissions and removals Term s an d d efi n i ti on s For the purposes of this docum ent, the following term s and definitions apply n o ch an g e i n atten u ati o n acceptance criterion for attenuation measurement that includes an allowance for measurement uncertainty arising from m easurement errors or calibration errors due to a lack of suitable reference standards Note to entry: For a practical interpretati on, th e followin g val ues shall be used: a) no ch ang e i n attenuation, singl e-m ode (Class B): th e total u n certainty of m easurem ent shall be ≤ ± 0, 05 dB for attenu ation or ≤± 0, 05 dB/km for attenuation coefficien t Any m easu red valu e withi n this range shall be considered as “n o change i n attenu ation ” The req uirem ent for these param eters is indicated as “No ch ange ( ≤ ± 0, 05 dB or ≤ ± 0, 05 d B/km )” By ag reem ent between custom er and su ppli er, m inor d evi ation from this lim it m ay be accepted at som e low freq uency, e g l ess than 0% However for m echanical tests no devi ation i n excess of 0, dB sh all be accepted For environm ental tests no d eviation i n excess of 0, dB/km shall be accepted b) no chan ge in attenu ation, m ultim ode (Category A1 ): the total uncertainty of m easurem ent shall be ≤ ± 0, dB for attenuati on or ≤ ± 0, dB/km for atten uati on coeffici ent Any m easured valu e within this ran ge shall be considered as “no change i n attenuati on” The req uirem ent for these param eters is indicated as “No ch ange ( ≤ ± 0, dB or ≤ ± 0, dB/km )” By ag reem ent between custom er and suppli er, m inor d evi ation from this lim it m ay be accepted at som e low freq uency, e g less than 0% However for m echanical tests no deviati on in excess of 0, dB shall be accepted For environm ental tests no d eviation i n excess of 0, dB/km shall be accepted c) no ch ang e i n attenuation, pl astic optical fi bre (Categ ory A4): the total uncertai nty of m easurem ent for this standard shall be ≤ % of m axim um specified atten uation in I EC 60793-2-40 Annex A to G Any m easured valu e within this ran ge shall be considered as “no change i n attenuati on ” al l owabl e ch an g e i n atten u ati o n change in attenuation that may be a value larger than the no change lim its, d epending on fibre category, single-m ode or multimode, cable design and application –8– I EC 60794-1 -1 : 201 © I EC 201 3 li n k desi gn atten u ation LD A statistical average attenuation value for a link of concatenated cables no ch an g e in fibre strai n acceptance criterion for fibre strain m easurem ent that includes an allowance for m easurem ent uncertainty arising from measurem ent errors or calibration errors due to a lack of suitable reference standards Note to entry: For a practical i nterpretation, th e total uncertai nty of m easu rem ent sh all be ± 0, 05 % strain An y m easured val ue within th is ran ge shall be consi dered as “n o change in strain ” al l owabl e ch an ge i n fi bre strai n level of strain that will not comprom ise fibre mechanical reliability for som e of the parameters specified Note to entry: For % proof-tested fibres, the fi bre strai n und er lon g term tensile load (T L ) sh all n ot exceed 20 % of this fibre proof strain (eq ual to absol ute 0, % strain ) and th ere shall be no ch ange in attenu ation d uri ng th e test Und er sh ort term tensile load (T S ) th e fibre strain shall not exceed 60 % of th e fibre proof strai n and th e attenu ation chan ge during test shall be m easu red an d record ed Other criteria m ay be agreed between th e custom er and th e suppl ier For fi bres proof tested at hi gh er levels th e safe l ong -term l oad will not scale linearly with proof strain, so a lower percentage of the proof strain is appl icabl e For g reater than % up to % proof-tested fibres, th e strai n at T L shall be l im ited to % of the proof-test strai n (equ al to absolute 0, 34 % strain for % proof tested fibres) cabl e l oad defin ition s (n on -aeri al appli cati on s) lon g term l oad TL acceptable amount of long term load which the cable may experience during operation (i e after installation is completed) Note to entry: Lon g term load m ay be due to resi dual load ing from the install ati on process and/or en vi ronm ental effect This is the rated m axim um load for which a cable is su bject to in long term tests sh ort term l oad TS TM acceptable amount of short-term load that can be applied to a cable without permanent degradation of the characteristics of the fibres, cable elements or sheath Note to entry: Sh ort term load is often cal led rated install ation load cabl e l oad defin ition s an d ten si l e testi n g termi n ol og y (self-su pportin g aerial appli cati on s) – 12 – I EC 60794-1 -1 : 201 © I EC 201 20 breakou t cabl e cable consisting of subunits which m ay be separate fibre optical cables surrounded by a sheath of suitable m aterial Note to entry: I n the application th is outer sheath of the breakout cable can be rem oved over a certain length and th e subunits can be used as separate fibre optic cabl es Graphi cal sym bol s an d abbrevi ati on s For the purposes of this document, the abbreviations given in I EC TR 61 931 as well as the following appl y ADSS APL ∆D ∆D’ D d dc DS ID I/O-port λ CC λ operati onal LDA m MAOC MAT MI T nxd n x OD n x O D’ OD OD’ OPAC OPGW PE RTS SPL SZ t1 TA1 all dielectric self-supporting aluminium/pol yeth ylene lam inate minimum wall thickness of a m icroduct minimum thickness of the outer sheath of a protected microduct nom inal outer diam eter of a microduct cable nom inal outer diam eter of a cable (including microduct fibre units) nom inal outer diam eter of a conduit or subduct detail specification nominal inner diameter of a microduct input/output port for launching OF cables into and out of a pipe cable cut-off wavelength operational wavelength link design attenuation (tbd) m ass of km of cable (in the context of tensile testing) m axim um allowable ovality of cable m axim um allowable tension m axim um installation tension The product of a variable and the cable outer diam eter used for determining appropriate sizes for bends, m andrels, etc The product of a variable and the outer diameter of a m icroduct used for determ ining appropriate sizes for bends, m andrels, etc The product of a variable and the outer diameter of a protected m icroduct used for determ ining appropriate sizes for bends, mandrels, etc nominal outer diameter of a microduct nominal outer diameter of a protected m icroduct optical attached cable (or optical power attached cable) optical ground wire polyeth ylene rated tensile strength steel/pol yeth ylene lam inate technique in which the lay reverses direction periodicall y temperature cycling dwell time temperature cycling test low-temperature lim it according to I EC 60794-1 -22, Method F1 I EC 60794-1 -1 : 201 © I EC 201 TA2 temperature cycling test secondary low-tem perature lim it according to I EC 60794-1 -22, Method F1 temperature cycling test high-temperature limit according to I EC 60794-1 -22, Method F1 temperature cycling test secondary high-temperature limit according to I EC 60794-1 -22, Method F1 long term load short term load weight of km of cable, m icroduct fibre unit or an y form of ducting, as applicable TB1 TB2 TL TS W – 13 – Opti cal fi bre cabl es Optical fibre cables, containing optical fibres and possibl y electrical conductors, consist of the following types: – – – – – – – – – – – – – – indoor cables; patch cords; prem ises cabling; cables for installation in ducts and lashed aerial cables; cables for direct burial; cables for installation in tunnels; aerial cables; drop cables; underwater cables for lakes, river crossings and coastal applications; m icroduct cabling; cables for utility rights of way such as sewers, gas pipes and water pipes; overhead cables (power lines); optical cables for rapid/m ultiple deploym ent; other optical fibre cable types not listed above M ateri al s 6 Opti cal fibre G en eral Optical fibres shall m eet the requirements of I EC 60793-2 Annex A gives guidance on application perform ance standards Atten u ati on coeffi cien t The m axim um cabled fibre attenuation coefficient shall conform to Annex A Particular values may be agreed between the customer and supplier The attenuation coefficient shall be m easured in accordance with I EC 60793-1 -40 Atten u ati on u n i formi ty – Atten u ati on d i scon ti n u i ti es The local attenuation shall not have point discontinuities in excess of 0, dB for single-mode fibre and 0, 20 dB for m ultim ode fibre, when m easured in accordance with I EC 60793 ‑ ‑ 40 – 14 – 6.1 I EC 60794-1 -1 : 201 © I EC 201 Cable cut-off wavelength For single-mode fibre, the cable cut-off wavelength λ cc shall be less than the operational wavelength, when measured in accordance with I EC 60793-1 -44 Unless otherwise stated, this shall be: a) b) c) d) λ cc ≤ 260 nm for fibre categories B1 , B1 and B6; λ cc ≤ 270 nm for fibre category B2; λ cc ≤ 450 nm for fibre categories B4 and B5; λ cc ≤ 530 nm for fibre category B1 6.1 Fibre colouring I f the primary coated fibres are coloured for identification, the coloured coating shall be readil y identifiable throughout the lifetime of the cable and shall be a reasonable m atch to I EC 60304 Refer to for the specification of fibre colour coding 6.1 Polarization mode dispersion (PM D) Cabled single-m ode fibre PMD shall be characterized on a statistical basis, not on an individual fibre basis, as described in I EC TR 61 282-3 Measurem ents on individual cabled fibres shall be perform ed in accordance with I EC 60793-1 -48 Measurem ents on uncabled fibre can be used to generate cabled fibre statistics when the design and processes are stable and the relationship between the PMD coefficients of uncabled and cabled fibre are known The m anufacturer shall suppl y a PMD link design value, PMD Q , that serves as a statistical upper bound PMD coefficient of the concatenated optical fibre cables within a possible optical link U nless otherwise specified in the detail specification, the PMD Q value shall be less than 0, ps/√ km with a probability of –4 that this value be exceeded for a numerical concatenation of at least 20 cables 6.2 Electrical condu ctors The characteristics of any electrical conductors shall be in accordance with the relevant I EC standards 6.3 Other materials Material used in the construction of optical fibre cables shall be com patible with the ph ysical and optical properties of the fibres and shall be in accordance with the relevant I EC standards 6.4 Environmental requirements When requested, inform ation shall be provided on the overall environm ental impact of the cable and cable material This information should include manufacturing, cable handling and environmental im pact during the lifetim e of the cable Exam ples of relevant inform ation are the m inim isation or replacement of harm ful materials and im provem ents in waste disposal Relevant standards include I SO 4001 and I SO 4064-1 7.1 Cable construction General The construction, dimensions, weight, mechanical, optical, electrical and climatic properties of each type of optical fibre cable shall be as stated in the relevant specification I EC 60794-1 -1 : 201 © I EC 201 7.2 Colour coding 7.2.1 Overview – 15 – Coding is essential to uniquel y identify each fibre in a cable Coding of fibres alm ost universall y involves colouring of the fibre coating or buffer (see 5) The coding schem e em ployed will usuall y require inclusion of coding of fibre, subunits, and units within the cable Coding schemes shall be agreed between m anufacturer and custom er The specific schem e is often the subject of regional norm s I EC 60304 identifies the colours to be used in fibre colouring, but does not address the coding Sheath colour coding m ay be used for a variety of purposes, and is most commonl y used in indoor cables Such sheath coding is used to identify the categories of fibre in the cable or the application of the cable, am ongst a num ber of other possibilities Unless otherwise specified, fibres shall be uniquel y identified by a scheme agreed between manufacturer and custom er As per 6.1 5, colours shall be a reasonable m atch to I EC 60304 Other colours or schem es may be used, as agreed 7.2.2 Unit colour coding If required as a part of the unique fibre identification scheme, units shall be uniquely identified If colours are used, they shall be a reasonable m atch to I EC 60304 I f other m ethods, such as a print string, positional identification, threads, etc are used, they shall conform to the intent of the identification schem e 7.2.3 Sheath colour coding Sheath colour coding, if used, shall be as agreed between m anufacturer and custom er Measuring methods 8.1 General Not all tests are applicable to all cables I ntrinsic characteristics of optical fibres are not norm all y m easured by cable manufacturers The relevant values are provided by optical fibre m anufacturers, available as unitary or statistical values For practical reasons, the core diameter of single-m ode fibres is not specified Mode field diam eter is the relevant specification param eter Test results shall follow the rule of “rounding half away from zero”, when the results recorded display more than the significant num ber of digits required in the acceptance criteria (see 8) Guidance on selecting fibres for testing is given in Annex B 8.2 Measuring methods for dimensions The dim ensions of the optical fibres, electrical conductors and cables shall be determ ined by subj ecting samples to tests selected from Table The tests applied, acceptance criteria and number of sam ples shall be as specified in the relevant specification – 16 – I EC 60794-1 -1 : 201 © I EC 201 Table – Measuring methods for dimensions Test method I EC 60793-1 -21 Test Coati ng g eom etry m easurem ent Characteristics covered by test method Diam eter of prim ary coatin g Diam eter of col ou red fibre Diam eter of second ary or “buffer” coating Non -circul arities of secon dary or “buffer” coatin g Prim ary coati ng -cladi ng concentricity error I EC 60793-1 -22 M ethod A Delay of transm itted an d/or refl ected pulse Len gth of fibre I EC 60793-1 -22 M ethod B Backscattering tech niq ue Len gth of fibre I EC 601 89-1 Mech anical Diam eter of electrical cond uctor I EC 6081 -201 Mech anical Thickness of insulati on – electrical conductors I EC 6081 -202 Thickness of sheaths I EC 6081 -203 8.3 Overal l dim ensions Measuring methods for mechanical characteristics The mechanical characteristics of optical fibre cables shall be verified by subj ecting sam ples to tests selected from I EC 60794-1 -21 The acceptance criteria shall be as specified in the relevant specification 8.4 Measuring methods for electrical characteristics When electrical conductors or other m etallic elem ents are incorporated in an optical fibre cable, verification of various electrical characteristics m ay be necessary Typical tests are shown in Table 2, in addition to those given in I EC 60794-1 -24 The tests applied and the acceptance criteria shall be as laid down in the relevant specification Table – Measuring methods for electrical characteristics Test method I EC 601 89-1 Test Characteri stics covered by test method Con ductor resistance Characteristics of insul ated electrical conductors Diel ectric stren gth of insulation The insu lation properti es of conductors withi n optical fibre cables are n orm all y just specified for the i ncom ing m aterial, pre-cabl i ng I nsulation resistance For cables installed along overhead power lines, specialised tests are given in I EC 60794-1 -24 (Method H1 : Short circuit test and Method H2: Lightning test method) and in I EC 60794-4-20: 201 2, Annex C (Electrical test (tracking)) 8.5 Measuring methods for transmission and optical characteristics The transm ission and optical characteristics of optical fibre in cables shall be verified by carrying out selected tests from those shown in Table The tests applied and acceptance criteria shall be as specified in the relevant specification I EC 60794-1 -1 : 201 © I EC 201 – 17 – Table – Measuring methods for transmission and optical characteristics of cabled optical fibres Test method Test Characteristics covered by the test method Test methods for multimode and single-mode fibre cabl es I EC 60793-1 -40 m ethod B I nsertion loss techni que Attenuati on I EC 60793-1 -40 m ethod C Backscattering tech niq ue Attenuati on I EC 60793-1 -40 m ethod C Backscattering tech niq ue Point defects I EC 60793-1 -46 m ethod A Transm itted power m onitori ng I EC 60793-1 -46 m ethod B Backscattering m onitoring Chang e of optical transm ittance durin g m echanical an d environm ental tests Test methods for single-mode fibres I EC 60793-1 -48 Polari zation m ode dispersion Polari zation m ode dispersion NOTE Band width, chrom atic dispersion and cable cut-off wavel ength are n ot m easured on cabled optical fi bre 8.6 Measuring methods for environmental characteristics The environm ental characteristics of optical fibre cables shall be verified by subjecting sam ples to tests selected from I EC 60794-1 -22 The tests applied and acceptance criteria shall be as specified in the relevant specification 8.7 Measuring methods for cable element characterisation Tests to characterise the different types of cable elements for handling purposes are given in I EC 60794-1 -23 Related Technical Reports Guidance to assist the user and installer with regard to the general aspects of the installation of optical fibre cables is covered by I EC TR 62691 [2] I EC TR 62222 [1 ] gives guidance on tests for assessing the fire performance of communication cables installed in buildings I EC TR 62362 [4] gives guidance on the selection of optical fibre cable specifications relative to mechanical, ingress, clim atic or electrom agnetic characteristics, as classified in I SO/I EC 24702 [9] An evaluation of h ydrogen induced effects within optical fibre cables is relevant for certain specialised designs, such as those for lakes, rivers, coastal and OPGW applications and those containing metallic tubes More details on when detailed consideration m ay be warranted are given in I EC TR 62690 [3] Guidelines on considerations that should be taken into account when testing optical fibres which are exposed to nuclear radiation are given in I EC TR 62283 [5] Guidelines on considerations that should be taken into account when planning to connect different types of singlem ode fibre are given in I EC/TR 62000 [6] Guidance on techniques for the measurem ent of the coefficient of friction between cables and ducts is given in I EC TR 62470 [7] _ Num bers in sq uare brackets refer to the Bi bliography – 18 – I EC 60794-1 -1 : 201 © I EC 201 An n e x A (informative) G u i d e l i n e s fo r s p e c i fi c d e fi n e d a p p l i c a t i o n s a n d c a b l e d fi b re p e rfo rm a n c e A G e n e l The fibre category should be agreed between customer and supplier Applications of optical fibre cables are defined by m an y different standards organisations including I EC, I SO, I EEE and I TU A C a b l e d fi b re a t t e n u a t i o n re q u i re m e n t s Cabled fibre attenuation requirem ents are given in Table A , Table A.2 and Table A T a b l e A – M axi m u m cabl ed fi b re a t t e n u a t i o n F i b re c a t e g o r y c o e ffi c i e n t ( d B / k m ) , M a xi m u m a tte n u a ti o n as g i ven b y I T U -T c o e ffi c i e n t ( d B / k m ) a t wa ve l e n g th s ( n m ) 31 nm 383 nm 550 nm 625 nm I EC 60793-2-50, B1 (d ispersion unshifted) – I TU-T G 652 A 0, n/a 0, n/a I EC 60793-2-50, B1 (d ispersion unshifted) – I TU-T G 652 B 0, n/a 0, 35 0, I EC 60793-2-50, B1 (cut-off shifted) – I TU-T G 654 A/B/C n/a n/a 0, 22 n/a I EC 60793-2-50, B1 (extend ed band) – I TU-T G 652 C 0, 0, 0, 0, I EC 60793-2-50, B1 (extend ed band) – I TU-T G 652 D 0, 0, 0, I EC 60793-2-50, B2 (dispersion shifted) – I TU-T G 653 C/D n/a n/a 0, 35 n/a I EC 60793-2-50, B4 (n on-zero dispersion shifted) – I TU-T G 655 C/D/E n/a n/a 0, 35 0, I EC 60793-2-50, B5 (wi deband non zero dispersi on shifted) – I TU-T G 656 n/a 0, (1 460) 0, 35 0, I EC 60793-2-50, B6_a1 , B6_a2 (bendi ng l oss insensitive) – I TU-T G 657 A1 /A2 0, 0, 0, 0, I EC 60793-2-50, B6_b2, B6_b3 (bendi ng l oss insensitive) – I TU-T G 657 B2/B3 0, 0, 0, (1 31 to 625) 0, (1 31 to 625) (1 31 to 625) 0, n/a = not applicabl e These values are more applicable to cables in the I EC 60794-3 [1 0] and I EC 60794-4 series, where used for long system applications (as defined by I TU -T) The introduction of link design attenuation (LDA) values is under consideration for certain fibre category Different attenuation values may be agreed between the customer and the supplier for certain cable constructions