1、BRITISH STANDARDBS EN 60079-27:2008Explosive atmospheres Part 27: Fieldbus intrinsically safe concept (FISCO)ICS 29.260.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g
2、44g42g43g55g3g47g36g58BS EN 60079-27:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2008 BSI 2008ISBN 978 0 580 56915 9National forewordThis British Standard is the UK implementation of EN 60079-27:2008. It is identical to IEC 60
3、079-27:2008. It supersedes BS EN 60079-27:2006, which will be withdrawn on 1 April 2011. The UK participation in its preparation was entrusted by Technical Committee GEL/31, Equipment for explosive atmospheres, to Subcommittee GEL/31/13, Intrinsically safe apparatus.A list of organizations represent
4、ed on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corr
5、igenda issued since publicationDate CommentsEUROPEAN STANDARD EN 60079-27 NORME EUROPENNE EUROPISCHE NORM May 2008 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue
6、 de Stassart 35, B - 1050 Brussels 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60079-27:2008 E ICS 29.260.20 Supersedes EN 60079-27:2006English version Explosive atmospheres - Part 27: Fieldbus intrinsically safe concept
7、(FISCO) (IEC 60079-27:2008) Atmosphres explosives - Partie 27: Concept de rseau de terrain de scurit intrinsque (FISCO) (CEI 60079-27:2008) Explosionsfhige Atmosphre - Teil 27: Konzept fr eigensichere Feldbussysteme (FISCO) (IEC 60079-27:2008) This European Standard was approved by CENELEC on 2008-0
8、4-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obt
9、ained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Cen
10、tral Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg,
11、Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Foreword The text of document 31G/169/CDV, future edition 2 of IEC 60079-27, prepared by SC 31G, Intrinsically-safe apparatus, of IEC TC 31, Equipment for explosive atmos
12、pheres, was submitted to the IEC-CENELEC Parallel Unique Acceptance Procedure and was approved by CENELEC as EN 60079-27 on 2008-04-01. This European Standard supersedes EN 60079-27:2006. The significant change with respect to EN 60079-27:2006 is that EN 60079-27:2008 replaces the FNICO requirements
13、 with the requirements of an “ic” FISCO system. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2009-01-01 latest date by which the national standards conflicting with the EN
14、have to be withdrawn (dow) 2011-04-01 This European Standard has been prepared under a mandate given to CENELEC by the European Commission and the European Free Trade Association and covers essential requirements of EC Directive (94/9/EC). See Annex ZZ. Annexes ZA and ZZ have been added by CENELEC.
15、_ Endorsement notice The text of the International Standard IEC 60079-27:2008 was approved by CENELEC as a European Standard without any modification. _ BS EN 60079-27:2008 2 CONTENTS 1 Scope.4 2 Normative references .4 3 Terms, definitions and abbreviations 5 3.1 Terms and definitions 5 3.2 Abbrevi
16、ations 5 4 Apparatus requirements .5 4.1 General .5 4.2 FISCO power supplies.5 4.2.1 General .5 4.2.2 Additional requirements of “ia” and “ib” FISCO power supplies 5 4.2.3 Additional requirements of “ic” FISCO power supplies .6 4.3 FISCO field devices.6 4.3.1 General .6 4.3.2 Additional requirements
17、 of “ia” and “ib” FISCO field devices 7 4.3.3 Additional requirement of “ic” FISCO field devices.7 4.4 Terminator.7 4.5 Simple apparatus 7 4.6 Marking .8 4.7 Examples of marking .8 5 System requirements9 5.1 General .9 5.2 Additional requirements of “ic” FISCO systems10 Annex A (informative) Typical
18、 system 11 Bibliography12 Figure A.1 Typical system11 Table 1 Assessment of maximum output current for use with “ia” and “ib” FISCO rectangular supplies6 Table 2 Assessment of maximum output current for use with “ic” FISCO rectangular supplies 6 Annex ZA (normative) Normative references to internati
19、onal publications with their corresponding European publications.13 Annex ZZ (informative) Coverage of Essential Requirements of EC Directives 14BS EN 60079-27:2008 3 EXPLOSIVE ATMOSPHERES Part 27: Fieldbus intrinsically safe concept (FISCO) 1 Scope This part of IEC 60079 contains the details of app
20、aratus, systems and installation practice for use with the Fieldbus Intrinsically Safe Concept (FISCO). It is based on the concepts of Manchester encoded, bus powered systems designed in accordance with IEC 61158-2 which is the physical layer standard for Fieldbus installations. The constructional a
21、nd installation requirements of FISCO apparatus and systems are determined by IEC 60079-11, IEC 60079-14, and IEC 60079-25, except as modified by this standard. Part of a Fieldbus device may be protected by any of the methods of explosion protection listed in IEC 60079-0, appropriate to the zone of
22、intended use. In these circumstances, the requirements of this standard apply only to that part of the apparatus directly connected to the intrinsically safe trunk or spurs. NOTE 1 Certification to the FISCO requirements does not prevent apparatus also being certified and marked to IEC 60079-11 in t
23、he conventional manner so that they may be used in other systems. Some apparatus certified before this standard was published but not necessarily complying with the electrical parameters of this standard may be marked “Suitable for FISCO systems”. This apparatus may be accepted in a FISCO system, if
24、 the comparison of the electrical parameters Uo, Io, Po, withUi, Ii, Pi, demonstrate compatibility with the remainder of the system, and all the other requirements of this standard are met. NOTE 2 A typical system is illustrated in Annex A. NOTE 3 Generally, “ic” FISCO systems are intended for use i
25、n zone 2 locations. FISCO systems are predominantly intended for use in zone 1 and 2 locations, but may enter zone 0 locations if specifically permitted to do so by the documentation. NOTE 4 Edition 1 of this standard introduced the FNICO concept to cover the use of Fieldbus concepts in zone 2 utili
26、zing the energy-limited nL concept. This standard substitutes the “ic” concept for the energy-limited concept, but permits the continued use of FNICO and nL apparatus. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated referenc
27、es, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60079-0, Explosive atmospheres Part 0: Equipment General requirements IEC 60079-11, Explosive atmospheres Part 11: Equipment protection by intrinsic safet
28、y “i” IEC 60079-14, Electrical apparatus for explosive gas atmospheres Part 14: Electrical installations in hazardous areas (other than mines) IEC 60079-15, Electrical apparatus for explosive gas atmospheres Part 15: Construction, test and marking of type of protection ”n” electrical apparatus IEC 6
29、0079-25, Electrical apparatus for explosive gas atmospheres Part 25: Intrinsically safe systems IEC 61158-2, Digital data communications for measurement and control Fieldbus for use in industrial control systems Part 2: Physical layer specification and service definition BS EN 60079-27:2008 4 3 Term
30、s, definitions and abbreviations 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in IEC 60079-0, IEC 60079-11 and IEC 60079-15 as well as the following apply. NOTE Additional definitions applicable to explosive atmospheres can be found in IEV 60050-426. 3
31、.2 Abbreviations FISCO Fieldbus Intrinsically Safe Concept FNICO Fieldbus Non-Incendive Concept 4 Apparatus requirements 4.1 General Apparatus shall be constructed in accordance with IEC 60079-11 except as modified by this standard. The apparatus documentation shall confirm that each apparatus is su
32、itable for use in a FISCO system in accordance with this standard. 4.2 FISCO power supplies 4.2.1 General The power supply shall either be resistive limited or have a trapezoidal or rectangular output characteristic. The maximum output voltage, Uo, shall be not greater than 17,5 V nor less than 14 V
33、 under the conditions specified in IEC 60079-11 for the respective level of protection. The maximum unprotected internal capacitance Ciand inductance Lishall be not greater than 5 nF and 10 H, respectively. The output from the power supply may be connected to earth. No specification of the internal
34、parameters Li and Cior the maximum external parameters Lo and Cois required on the certificate or label. The determination of power supply output parameters shall take into account the possible opening, shorting and earthing of field wiring connected to the field terminals of the apparatus. 4.2.2 Ad
35、ditional requirements of “ia” and “ib” FISCO power supplies The maximum output current Iofor any “ia” or “ib” FISCO power supply shall be determined in accordance with IEC 60079-11 but shall not exceed 380 mA. For rectangular supplies, Table 1 may be used for assessment. BS EN 60079-27:2008 5 Table
36、1 Assessment of maximum output current for use with “ia” and “ib” FISCO rectangular supplies UoV Permissible current, for IIC (includes 1,5 safety factor) mA Permissible current, for IIB (includes 1,5 safety factor) mA 14 183 380 15 133 354 16 103 288 17 81 240 17,5 75 213 NOTE The two largest curre
37、nt values for IIB are derived from 5,32 W. The maximum output power Poshall not exceed 5,32 W. 4.2.3 Additional requirements of “ic” FISCO power supplies The maximum output current Iofor an “ic” FISCO power supply shall be determined in accordance with IEC 60079-11. For “ic” FISCO rectangular suppli
38、es, Table 2 may be used for assessment. Table 2 Assessment of maximum output current for use with “ic” FISCO rectangular supplies UoV Permissible current, for IIC mA Permissible current, for IIB mA 14 274 570 15 199 531 16 154 432 17 121 360 17,5 112 319 NOTE The maximum output power Pofrom “ic” FIS
39、CO power supplies is not restricted to 5,32 W. 4.3 FISCO field devices 4.3.1 General These requirements apply to apparatus other than the power supply terminators and simple apparatus connected to the intrinsically safe bus whether installed inside or outside the hazardous area. In addition to the r
40、elevant sections of IEC 60079-11, hand held terminals shall comply with the requirements for field terminals. The requirements are as follows: a) field devices shall have a minimum input voltage parameter of Ui= 17,5 V; b) the maximum unprotected internal capacitance Ci of each field device shall be
41、 not greater than 5 nF; c) the bus terminals shall be isolated from earth in accordance with IEC 60079-11; d) the bus terminals of separately powered field devices shall be galvanically isolated from other sources of power in accordance with IEC 60079-11, so as to ensure that these terminals remain
42、passive and multiple earthing of the bus is avoided; BS EN 60079-27:2008 6 e) under normal or fault conditions as specified in IEC 60079-11 the bus terminals shall remain passive, that is the terminals shall not be a source of energy to the system except for a leakage current not greater than 50 A;
43、f) field devices shall be allocated a level of protection and be suitable for apparatus group IIC in accordance with IEC 60079-11; g) field devices intended to be installed within the hazardous area shall be temperature classified in accordance with IEC 60079-11. 4.3.2 Additional requirements of “ia
44、” and “ib” FISCO field devices The additional requirements of “ia” and “ib” FISCO field devices are as follows: a) field devices shall have minimum input parameters of Ii = 380 mA and Pi = 5,32 W; b) field devices shall have an internal inductance Linot greater than 10 H. 4.3.3 Additional requiremen
45、t of “ic” FISCO field devices The additional requirement of “ic” FISCO field devices is that they shall have an internal inductance Linot greater than 20 H. 4.4 Terminator The line terminators required by the system shall comprise a resistor-capacitor combination, which presents at its terminals a c
46、ircuit equivalent to a resistor of minimum value 90 in series with a capacitor of maximum value 2,2 F (including tolerances). NOTE 1 IEC 61158-2 specifies the component values necessary for operational reasons. The terminator shall a) be allocated a level of protection and be suitable for apparatus
47、group IIC; b) have an input voltage parameter Uinot less than 17,5 V; NOTE 2 If the capacitive component(s) are considered to be able to fail to create a short circuit then the required power rating of the resistor(s) is 5,1 W and the temperature class should be determined with a power dissipation o
48、f 3,4 W. c) be isolated from earth in accordance with IEC 60079-11; d) have a maximum unprotected internal inductance Linot greater than 10 H; e) terminators intended to be installed within the hazardous area shall be temperature classified in accordance with IEC 60079-11. The terminators may be inc
49、orporated within field devices or power supplies. NOTE 3 For safety assessment purposes, the effective capacitance (Ci) of the terminator is considered not to affect the intrinsic safety of the system. 4.5 Simple apparatus The requirement of simple apparatus used in an intrinsically safe system is that it shall comply with IEC 60079-11. The capacitance and inductance of the simple apparatus shall be known so that the system requirement in 5.1 can be assessed. The total inductance and capacitance of each s
