1、BSI Standards PublicationOverhead electrical lines exceeding AC 45 kVPart 2-20: National Normative Aspects (NNA) for ESTONIA (based on EN 50341-1:2012)BS EN 50341-2-20:2015BS EN 50341-2-20:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 50341-2-20:2015.It i
2、s based on EN 50341-1:2012.This standard, together with the following list of National NormativeAspect standards, supersedes BS EN 50423-3:2005 and BS EN 50341-3:2001:Country Code Origin Ref AT Austrian National Committee BS EN 50341-2-1 BE Belgian National Committee BS EN 50341-2-2 CH Swiss Nationa
3、l Committee BS EN 50341-2-3 DE German National Committee BS EN 50341-2-4 DK Danish National Committee BS EN 50341-2-5 ES Spanish National Committee BS EN 50341-2-6 FI Finnish National Committee BS EN 50341-2-7 FR French National Committee BS EN 50341-2-8 GB British National Committee BS EN 50341-2-9
4、 GR Greek National Committee BS EN 50341-2-10 IE Irish National Committee BS EN 50341-2-11 IS Iceland National Committee BS EN 50341-2-12 IT Italian National Committee BS EN 50341-2-13 LU Luxemburg National Committee No NNA available NL Nederlands National Committee BS EN 50341-2-15 NO Norwegian Nat
5、ional Committee BS EN 50341-2-16 PT Portuguese National Committee BS EN 50341-2-17 SE Swedish National Committee BS EN 50341-2-18 CZ Czech National Committee BS EN 50341-2-19EE Estonian National Committee BS EN 50341-2-20:2015 SI Slovak National Committee BS EN 50341-2-21 PL Polish National Committe
6、e BS EN 50341-2-22 BS EN 50423-3:2005 and BS EN 50341-3:2001 will be withdrawn uponpublication of the rest of the series.The UK participation in its preparation was entrusted to TechnicalCommittee PEL/11, Overhead Lines.A list of organizations represented on this committee can be obtainedon request
7、to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 89873 0 ICS 29.240.20 Compliance with a British Sta
8、ndard cannot confer immunity from legal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 31 May 2015.Amendments/corrigenda issued since publicationDate Text affectedEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 50341-2-20 Februa
9、ry 2015 ICS 29.240.20 English Version Overhead electrical lines exceeding AC 45 kV - Part 2-20: National Normative Aspects (NNA) for ESTONIA (based on EN 50341-1:2012) This European Standard was approved by CENELEC on 2015-01-06. CENELEC members are the national electrotechnical committees of Austri
10、a, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
11、 Sweden, Switzerland,Turkey and the United Kingdom. European Committee for Electrotechnical Standardization Comit Europen de Normalisation ElectrotechniqueEuropisches Komitee fr Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CENELEC All rights of expl
12、oitation in any form and by any means reserved worldwide for CENELEC Members. Ref. No. EN 50341-2-20:2015 E EN 50341-2-20:2015 2 / 42 Estonia CONTENTS 0 Introduction .5 0.7 Language 5 1 Scope 5 1.1 General .5 1.2 Field of application 5 2 Normative references, definitions and symbols 6 2.1 Normative
13、references6 3 Basis of design 8 3.2 Requirements of overhead lines .8 3.3 Limit states 9 3.4 Actions 9 3.6 Design values .9 4 Actions on lines .9 4.1 Introduction .9 4.3 Wind loads 9 4.4 Wind forces on overhead line components . 10 4.5 Ice loads . 11 4.6 Combined wind and ice loads 11 4.7 Temperatur
14、e effects . 11 4.8 Security loads 11 4.9 Safety Loads 12 4.10 Forces due to short-circuit currents . 13 4.11 Other special forces . 13 4.12 Load cases . 13 4.13 Partial factors for actions . 14 5 Electrical requirements 16 5.1 Introduction 16 5.2 Currents . 16 5.4 Classification of voltages and over
15、voltages . 16 5.5 Minimum air clearance distances to avoid flashover . 17 5.6 Load cases for calculation of clearances . 17 5.8 Internal clearances within the span and at the top of support . 18 5.9 External clearances . 18 5.10 Corona effect . 26 6 Earthing systems . 27 6.1 Introduction 27 6.2 Rati
16、ngs with regard to corrosion and mechanical strength 27 6.4 Dimensioning with regard to human safety . 27 7 Supports . 28 7.2 Materials 28 7.3 Lattice steel towers 28 7.4 Steel poles . 29 7.5 Wood poles 29 7.9 Corrosion protection and finishes 30 7.10 Maintenance facilities. 30 8 Foundations . 30 8.
17、1 Introduction 30 8.2 Basis of geotechnical design . 30 8.3 Soil investigation and geotechnical data 31 9 Conductors and earth-wires . 32 9.2 Aluminium based conductors . 32 9.3 Steel based conductors . 32 9.5 Conductors and ground wires containing optical fibre telecommunication circuits . 32 BS EN
18、 50341-2-20:2015EN 50341-2-20:2015 2 / 42 Estonia CONTENTS 0 Introduction .5 0.7 Language 5 1 Scope 5 1.1 General .5 1.2 Field of application 5 2 Normative references, definitions and symbols 6 2.1 Normative references6 3 Basis of design 8 3.2 Requirements of overhead lines .8 3.3 Limit states 9 3.4
19、 Actions 9 3.6 Design values .9 4 Actions on lines .9 4.1 Introduction .9 4.3 Wind loads 9 4.4 Wind forces on overhead line components . 10 4.5 Ice loads . 11 4.6 Combined wind and ice loads 11 4.7 Temperature effects . 11 4.8 Security loads 11 4.9 Safety Loads 12 4.10 Forces due to short-circuit cu
20、rrents . 13 4.11 Other special forces . 13 4.12 Load cases . 13 4.13 Partial factors for actions . 14 5 Electrical requirements 16 5.1 Introduction 16 5.2 Currents . 16 5.4 Classification of voltages and overvoltages . 16 5.5 Minimum air clearance distances to avoid flashover . 17 5.6 Load cases for
21、 calculation of clearances . 17 5.8 Internal clearances within the span and at the top of support . 18 5.9 External clearances . 18 5.10 Corona effect . 26 6 Earthing systems . 27 6.1 Introduction 27 6.2 Ratings with regard to corrosion and mechanical strength 27 6.4 Dimensioning with regard to huma
22、n safety . 27 7 Supports . 28 7.2 Materials 28 7.3 Lattice steel towers 28 7.4 Steel poles . 29 7.5 Wood poles 29 7.9 Corrosion protection and finishes 30 7.10 Maintenance facilities. 30 8 Foundations . 30 8.1 Introduction 30 8.2 Basis of geotechnical design . 30 8.3 Soil investigation and geotechni
23、cal data 31 9 Conductors and earth-wires . 32 9.2 Aluminium based conductors . 32 9.3 Steel based conductors . 32 9.5 Conductors and ground wires containing optical fibre telecommunication circuits . 32 BS EN 50341-2-20:2015Estonia 3 / 42 EN 50341-2-20:2015 9.6 General requirements . 32 10 Insulator
24、s 32 10.2 Standard electrical requirements 32 10.4 Pollution performance requirements . 33 10.7 Mechanical requirements 33 10.10 Characteristics and dimensions of insulators . 33 11 Hardware 34 11.6 Mechanical requirements 34 12 Quality assurance, checks and taking-over 34 Annex B (informative) Conv
25、ersion of wind velocities and ice loads 35 Annex C (informative) Application examples of wind loads Special forces 36 Annex E (normative) Theoretical method for calculating minimum air clearances . 37 Annex F (informative) Empirical method for calculating mid span clearances 38 Annex G (normative) C
26、alculation methods for earthing systems 39 Annex H (informative) Installation and measurements of earthing systems . 40 Annex M (informative) Geotechnical and structural design of foundations . 42 BS EN 50341-2-20:2015EN 50341-2-20:2015 4 / 42 Estonia FOREWORD 1 The Estonian National Committee (NC)
27、is identified by the following address Estonian Centre for Standardisation Estonian National High Voltage Committee (HVC) Aru str. 10, 10317 Tallinn, Estonia Phone: +372 605 5050 Fax: +372 605 5070 e-mail: infoevs.ee 2 The Estonian NC has prepared this Part 2-20 of EN 50341, listing the Estonian nat
28、ional normative aspects under its sole responsibility, and has duly passed it through the CENELEC and CLC/TC 11 procedures. NOTE: The Estonian NC also takes sole responsibility for the technically correct co-ordination of this NNA with EN 50341-1. It has performed the necessary checks in the frame o
29、f quality assurance / control. However, it is noted that this quality control has been made in the framework of the general responsibility of a standards committee under the national laws / regulations. 3 This Part 2-20 is normative in Estonia and informative for other countries. 4 This Part 2-20 ha
30、s to be read in conjunction with EN 50341-1, referred to hereafter as Part 1. All clause numbers used in this Part 2-20 correspond to those in Part 1. Specific subclauses, which are prefixed “EE”, are to be read as amendments to the relevant articles in Part 1. Any necessary clarification regarding
31、the application of Part 2-20 in conjunction with Part 1 shall be referred to the Estonian NC that will, in cooperation with CLC/TC 11, clarify the requirements. When no reference is made in Part 2-20 to a specific subclause, Part 1 applies. 5 In the case of “box values” defined in Part 1, amended va
32、lues (if any), which are defined in Part 2-20, shall be taken into account in Estonia. However any boxed value, whether in Part 1 or Part 2-20, shall not be amended in the direction of greater risk in the Project Specification. Terms with prepositions “from” and “up to”, denoting boundaries of value
33、s, always include the boundary values itself, as it is common in other Estonian normative documents. 6 The national Estonian standards/regulations related to overhead electrical lines exceeding AC 1 kV are identified/listed in Clause 2 of this Part 2-20. NOTE All national standards referred to in th
34、is Part 2-20 will be replaced by the relevant European Standards as soon as they become available and are declared by the Estonian Centre for Standardisation to be applicable and thus reported to the secretary of CLC/TC 11. BS EN 50341-2-20:2015EN 50341-2-20:2015 4 / 42 Estonia FOREWORD 1 The Estoni
35、an National Committee (NC) is identified by the following address Estonian Centre for Standardisation Estonian National High Voltage Committee (HVC) Aru str. 10, 10317 Tallinn, Estonia Phone: +372 605 5050 Fax: +372 605 5070 e-mail: infoevs.ee 2 The Estonian NC has prepared this Part 2-20 of EN 5034
36、1, listing the Estonian national normative aspects under its sole responsibility, and has duly passed it through the CENELEC and CLC/TC 11 procedures. NOTE: The Estonian NC also takes sole responsibility for the technically correct co-ordination of this NNA with EN 50341-1. It has performed the nece
37、ssary checks in the frame of quality assurance / control. However, it is noted that this quality control has been made in the framework of the general responsibility of a standards committee under the national laws / regulations. 3 This Part 2-20 is normative in Estonia and informative for other cou
38、ntries. 4 This Part 2-20 has to be read in conjunction with EN 50341-1, referred to hereafter as Part 1. All clause numbers used in this Part 2-20 correspond to those in Part 1. Specific subclauses, which are prefixed “EE”, are to be read as amendments to the relevant articles in Part 1. Any necessa
39、ry clarification regarding the application of Part 2-20 in conjunction with Part 1 shall be referred to the Estonian NC that will, in cooperation with CLC/TC 11, clarify the requirements. When no reference is made in Part 2-20 to a specific subclause, Part 1 applies. 5 In the case of “box values” de
40、fined in Part 1, amended values (if any), which are defined in Part 2-20, shall be taken into account in Estonia. However any boxed value, whether in Part 1 or Part 2-20, shall not be amended in the direction of greater risk in the Project Specification. Terms with prepositions “from” and “up to”, d
41、enoting boundaries of values, always include the boundary values itself, as it is common in other Estonian normative documents. 6 The national Estonian standards/regulations related to overhead electrical lines exceeding AC 1 kV are identified/listed in Clause 2 of this Part 2-20. NOTE All national
42、standards referred to in this Part 2-20 will be replaced by the relevant European Standards as soon as they become available and are declared by the Estonian Centre for Standardisation to be applicable and thus reported to the secretary of CLC/TC 11. BS EN 50341-2-20:2015Estonia 5 / 42 EN 50341-2-20
43、:2015 0 INTRODUCTION 0.7 Language (snc) EE.1 Language This Part 2-20 is published in English and in Estonian. 1 SCOPE 1.1 General (NCPT) EE.1 Application to new lines This Part 2-20 applies to all new overhead electric lines with nominal system voltages exceeding AC 1 kV and with rated frequencies b
44、elow 100 Hz. This standard also applies to D.C. overhead lines in structural aspects. (NCPT) EE.2 “New overhead line” A “new overhead line” means a completely new line between two points, A and B. A new branch line of the existing power line should be considered as a new power line including the jun
45、ction support, for which specific requirements should be defined in the Project Specification. 1.2 Field of application (A-dev) EE.1 Application to mounting of telecommunication equipment The Standard EVS-EN 50341:2012 is applicable to fixing of structural elements for tele-communication (antennas,
46、satellite dishes, All Dielectric Self Supporting (ADSS) equipment, etc.), if mounted on power line supports (towers), especially regarding wind forces and ice loads on such fixed elements. The design and installation should be done under the due control of the line owner and/or the competent authori
47、ty. Mounting of telecommunication equipment on power line supports must be coordinated with line owner and stated in the Project Specification. If telecommunication equipment (antennas, dishes, etc.) will be installed in the transmission line supports, and their size, location or mounting will have
48、major effects on the loads or design of the structures, the requirements of EVS-EN 1993-3 will also have to be taken into account. If such structures include conductive parts, the requirements on clearances in Section 5.8 should be applied. (NCPT) EE.2 Application to existing overhead lines The Stan
49、dard EVS-EN 50341:2012 shall not be applied to maintenance, reconductoring, tee-offs, extensions or diversions to existing overhead lines in Estonia, unless specifically required in the Project Specification. In cases of major revisions of existing lines the degree of application of the Standard EVS-EN 50341:2012 should be agreed upon by the parties concerned and specified in the Project Specification. (NCPT) EE.3 Application to installations under construction or design Installations in the design and construction stage may be completed by using the standard valid at the begin
