SIST EN 50341-2-21:2023
(Main)Overhead electrical lines exceeding AC 1 kV - National Normative Aspects (NNA) for Slovenia (based on EN 50341-1:2012)
Overhead electrical lines exceeding AC 1 kV - National Normative Aspects (NNA) for Slovenia (based on EN 50341-1:2012)
SI.1 Definition of the new overhead power line A new overhead power line is defined as a functionally completed installation for the transmission of electricity between points A and B (i.e. the new construction of all conductors, their supports together with foundations, earthing system, insulators, accessories and fittings).
The overhead lines currently being designed (starting of a design to obtain a building permit) or being under construction may be completed in accordance with the standards
in force at the time of the start of the design or construction of the overhead line.
In the case of maintenance and renovation works with major structural changes to overhead lines, this standard shall be applied in accordance with the project specification. E.g., for the construction of new support on new foundations in the existing overhead line, the provisions of this standard shall be applied to support and foundations
but for the other elements of the overhead line don’t need to be complied with this standard.
For the design and construction of DC overhead lines, the requirements of this standard are also applicable to the design of structures, but not for electrical requirements, which have to be specified in the project specification.
Nadzemni električni vodi za izmenične napetosti nad 1 kV - Nacionalna normativna določila (NNA) za Slovenijo (na podlagi EN 50341-1:2012)
Nov nadzemni električni vod je opredeljen kot vod, ki predstavlja funkcionalno zaključeno celoto za prenos električne energije med točkama A in B (to pomeni novogradnjo vseh podpor s temelji, vodnikov z izolatorji in obesno opremo ter sistemi ozemljitve).
Objekti, ki se v času izdaje standarda projektirajo (začetek izdelave projekta za pridobitev
gradbenega dovoljenja) ali gradijo, se lahko zaključijo v skladu s standardi, ki so bili veljavni ob
začetku projektiranja ali gradnje nadzemnega voda.
Pri vzdrževalnih in obnovitvenih delih z večjimi konstrukcijskimi spremembami nadzemnega
voda je treba ta standard uporabiti skladno z določili projektne naloge. Npr., pri gradnji nove
podpore na novih temeljih v trasi obstoječega voda je treba za podporo in temelje uporabiti
določila tega standarda, za ostale elemente napenjalnega polja pa določil tega standarda ni
treba upoštevati.
Pri projektiranju in gradnji nadzemnih vodov enosmerne napetosti so zahteve iz tega standarda uporabne tudi pri oblikovanju konstrukcij, vendar ne za električne zahteve, ki jih je treba določiti v projektni nalogi.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2023
Nadzemni električni vodi za izmenične napetosti nad 1 kV - Nacionalna normativna
določila (NNA) za Slovenijo (na podlagi EN 50341-1:2012)
Overhead electrical lines exceeding AC 1 kV - National Normative Aspects (NNA) for
Slovenia (based on EN 50341-1:2012)
Ta slovenski standard je istoveten z: EN 50341-2-21:2023
ICS:
29.240.20 Daljnovodi Power transmission and
distribution lines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN 50341-2-21
NORME EUROPÉENNE
EUROPÄISCHE NORM July 2023
ICS 29.240.20
English Version
Overhead electrical lines exceeding AC 1 kV - National
Normative Aspects (NNA) for Slovenia (based on
EN 50341-1:2012)
This European Standard was approved by CENELEC on 2023-05-31. 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 obtained on application to the CEN-CENELEC
Management Centre 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-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 50341-2-21:2023 E
Contents Page
European foreword . 5
1.1 General . 6
1.2 Field of application . 6
2. Normative references, definitions, and symbols . 6
2.1 Normative references . 6
2.2 Definitions . 8
2.3 Symbols . 8
3. Basis of design . 8
3.2 Requirements of overhead lines . 8
3.2.2 Reliability requirements . 8
3.3 Limit states . 9
3.3.1 General . 9
4. Actions on lines . 9
4.1 Introduction . 9
4.2 Permanent loads . 9
4.3 Wind loads . 9
4.3.1 Field of application and basic wind velocity . 9
4.3.2 Mean wind velocity . 10
4.3.3 Mean wind pressure . 11
4.3.4 Turbulence intensity and peak wind pressure . 11
4.4 Wind forces on overhead line components . 11
4.4.1 Wind forces on conductors . 11
4.4.2 Wind loads on insulator sets . 12
4.4.3 Wind forces on lattice towers . 12
4.4.4 Wind forces on poles . 13
4.5 Ice loads . 13
4.5.1 General . 13
4.5.2 Ice forces on conductors . 14
4.6 Combined wind and ice loads . 14
4.6.1 Combined probabilities . 14
4.6.2 Drag factors and ice densities . 15
4.6.3 Mean wind pressure and peak wind pressure . 15
4.6.6 Combination of wind velocities and ice loads . 15
4.7 Temperature effects . 15
4.8 Security loads . 15
4.8.1 General . 15
4.9 Safety loads . 15
4.9.1 Construction and maintenance loads . 16
4.11 Other special forces . 16
4.11.1 Avalanches, creeping snow . 16
4.11.2 Earthquakes . 16
Slovenia 3/54 EN 50341-2-21:2023
4.12 Load cases . 16
4.12.1 General . 16
4.12.2 Standard load cases . 17
4.13 Partial factors for actions . 19
5. Electrical requirements . 21
5.2 Currents . 21
5.2.1 Normal current . 21
5.3 Insulation co-ordination . 21
5.4 Classification of voltages and overvoltages . 22
5.4.2 Representative power frequency voltages . 22
5.4.5 Representative fast-front overvoltages . 22
5.5 Minimum air clearance to avoid flashover . 23
5.5.3 Empirical method based on European experience . 23
5.6 Load cases for calculation of clearances . 24
5.6.2 Maximum conductor temperature . 24
5.6.3 Wind loads for determination of electric clearances . 24
5.6.4 Ice loads for determination of electric clearances . 25
5.6.5 Combined wind and ice loads . 25
5.8 Internal clearances within the span and at the top of support . 26
5.9 External clearances . 27
5.9.1 General . 27
5.9.2 External clearances to ground in areas remote from buildings, roads, etc. . 28
5.9.3 External clearances to residential and other buildings . 29
5.9.5 External clearances to adjacent traffic routes . 30
5.9.6 External clearances to other power lines or overhead telecommunication lines . 31
5.9.7 External clearances to recreational areas (playgrounds, sports areas, etc.) . 32
5.10 Corona effect . 32
5.10.1 Radio noise . 32
5.10.2 Audible noise . 33
5.11 Electric and magnetic fields . 33
5.11.1 Electric and magnetic fields under overhead line . 33
5.11.2 Electric and magnetic field induction . 33
5.11.3 Interference with telecommunications circuits . 33
6 Earthing systems . 33
6.1 Introduction . 33
6.1.3 Earthing measures against lighting effects . 33
6.1.4 Transferred potentials . 35
6.3 Dimensioning with regard to thermal strength . 35
6.3.2 Current rating calculation . 35
6.4 Dimensioning with regard to human safety . 35
6.4.2 Touch voltage limits at different locations . 35
6.5 Site inspection and documentation of earthing systems . 36
7 Supports . 36
7.1 Initial design considerations . 36
7.2 Materials . 36
7.2.1 Steel materials, bolts, nuts and washers, welding consumables . 36
(ncpt) SI.1 Materials for steel components . 36
7.3 Lattice steel towers . 37
7.3.1 General . 37
7.3.5 Structural analysis . 37
7.3.6 Ultimate limit states . 37
7.3.8 Resistance of connections . 37
7.4 Steel poles . 38
7.4.1 General . 38
7.4.7 Serviceability limit states (EN 1993-1-1:2005 – Chapter 7) . 38
7.4.8 Resistance of connections . 39
7.5 Wood poles . 39
7.5.5 Ultimate limit states . 39
7.5.7 Resistance of connections . 40
7.6 Concrete poles . 40
7.9 Corrosion protection and finishes . 40
7.9.1 General . 40
7.10 Maintenance facilities . 40
7.10.1 Climbing . 40
7.10.2 Maintainability . 41
8 Foundations . 42
8.1 Introduction . 42
8.2 Basis of geotechnical design (EN 1997-1:2004, chapter 2) . 42
8.2.2 Geotechnical design by calculation . 42
9 Conductors and earth-wires . 44
9.2 Aluminium based conductors . 44
9.2.1 Characteristics and dimensions . 44
9.2.3 Conductors service temperatures and grease characteristics . 44
9.3 Steel based conductors . 45
9.6 General requirements. 45
10 Insulators . 46
10.2 Standard electrical requirements . 46
10.7 Mechanical requirements . 46
11.5 Short circuit current and power arc requirements . 47
11.6 Mechanical requirements . 48
Annex G (normative): Calculation methods for earthing systems . 50
Annex J (normative): Angles in lattice steel towers . 51
Annex M (informative): Geotechnical and structural design of foundations . 52
Table M.4/SI.1 Soil characteristics for design of foundations (Slovenia) . 53
Slovenia 5/54 EN 50341-2-21:2023
European foreword
The following statements 1 to 6 are required from CLC/TC 11 for all NNAs.
1 The Slovenian National Technical Committee is identified by the following address:
Slovenski Inštitut za Standardizacijo (SIST)
Ulica gledališča BTC 2
SI-1000 Ljubljana, SLOVENIA
phone ++386 1 478 3013
e-mail: sist@sist.si
Name of the relevant technical body: SIST/TC NVV Technical Committee for Overhead
lines and conductors.
2 The Slovenian NC and its technical body NVV “Overhead power lines and conductors” of
SIST prepared this Part 2-21 of EN 50341, listing the Slovenian National Normative Aspects
(NNA) under its sole responsibility, and duly passed it through the CENELEC and CLC/TC
11 procedures.
NOTE: The Slovenian NC also takes sole responsibility for the technically correct co-ordination of
this EN 50341-2-21 with EN 50341-1:2012. It performed the necessary checks in the frame of quality
assurance/control. However, it is noted that this quality control was made in the framework of the
general responsibility of a standards committee under the national laws/regulations.
3 This EN 50431-2-21, hereafter referred to as Part 2-21, is normative in Slovenia and
informative in other countries.
4 This Part 2-21 shall be read in conjunction with EN 50341-1, hereafter referred to as Part
1. All clause numbers used in this NNA correspond to those of Part 1. Specific subclauses,
which are prefixed “SI”, shall be read as amendments to the relevant text in Part 1. Any
necessary clarification regarding the application of this NNA in conjunction with Part 1 shall
be referred to the Slovenian NC who will, in co-operation with CLC/TC 11, clarify the
requirements.
When no reference is made in this NNA to a specific subclause, then Part 1 applies.
5 In case of “boxed values” defined in Part 1, amended values, (if any) which are defined in
Part 2-21 shall be considered in Slovenia.
However, any “boxed value”, whether in Part 1 or in this Part 2-21, shall not be amended
in the direction of greater risk in a Project Specification.
6 The Slovenian National standards/regulations related to overhead electrical lines
exceeding 1 kV AC are listed in subclause 2.1 SI.1 of this Part 2-21.
NOTE All national standards referred to in this Part 2-21 will be replaced by the relevant European
Standards as soon as they become available and are declared by the Slovenian NC to be applicable
and thus reported to the secretary of CLC/TC 11.
1. Scope
1.1 General
(A-dev) SI.1 Definition of the new overhead power line
A new overhead power line is defined as a functionally completed installation for the
transmission of electricity between points A and B (i.e. the new construction of all
conductors, their supports together with foundations, earthing system, insulators,
accessories and fittings).
The overhead lines currently being designed (starting of a design to obtain a building
permit) or being under construction may be completed in accordance with the standards
in force at the time of the start of the design or construction of the overhead line.
In the case of maintenance and renovation works with major structural changes to
overhead lines, this standard shall be applied in accordance with the project
specification. E.g., for the construction of new support on new foundations in the existing
overhead line, the provisions of this standard shall be applied to support and foundations
but for the other elements of the overhead line don’t need to be complied with this
standard.
For the design and construction of DC overhead lines, the requirements of this standard
are also applicable to the design of structures, but not for electrical requirements, which
have to be specified in the project specification.
1.2 Field of application
(ncpt) SI.1 Conductors with optical fiber wires
This standard is also applicable for designing and construction of conductors with fiber
optic wires (OPPC), optical ground wires (OPGW) and ADSS (All Dielectric Self
Supporting) cables.
(ncpt) SI.2 Use of cover conductors and overhead insulated cable networks
In overhead lines with covered conductors, insulated by artificial mass and overhead
insulated cable networks up to and including 45 kV, project requirements shall be defined
in the project specification.
(ncpt) SI.3 Use for the installation of other equipment on supports
This Standard also applies to all other equipment intended for installation of new
overhead line supports. Other equipment shall be considered as the equipment which
does not belong to the basic elements of the overhead line, e. g. equipment for the
passage of overhead line into cable, disconnectors, telecommunications equipment,
meteorological equipment, measuring equipment and more. Static verification of the
support and foundation of the overhead water must be carried out due to the impact of
the self-weight of other equipment and the impact of wind and ice on other equipment.
2. Normative references, definitions, and symbols
2.1 Normative references
All standards referred to in the text in this Standard are listed in EN 50341-1:2012. In
addition to these standards, the design and construction of overhead lines above 1 kV in
Slovenia must consider the applicable national legislation and regulations related to
spatial placement and safety, and quality.
(A-dev) SI.1 National normative acts and regulations, to be taken into account when designing
and building overhead lines in Slovenia are:
Slovenia 7/54 EN 50341-2-21:2023
Energy Act, (Uradni list RS, št. 60/19, 65/20, 158/20 – ZURE, 121/21 – ZSROVE, 172/21 – ZOEE,
204/21 – ZOP in 44/22 – ZOTDS)
Building Act (Uradni list RS, št. 199/21 in 105/22 – ZZNŠPP)
Rules on technical conditions for the construction of overhead high voltage lines of alternating
current from 1kV to 400 kV (Uradni list RS, št. 52/14 in 67/22)
Spatial Planning Act (Uradni list RS, št. 33/07, 70/08 – ZVO-1B, 108/09, 80/10 – ZUPUDPP, 43/11
– ZKZ-C, 57/12, 57/12 – ZUPUDPP-A, 109/12, 76/14 – odl. US, 14/15 – ZUUJFO, 61/17 – ZUreP-
2 in 199/21 – ZUreP-3)
Decree on the assessment and management of environmental noise (Uradni list RS, št. 121/04,
59/19, 44/22 – ZVO-2 in 53/22)
Spatial Management Act Uradni list RS, št. 199/21)
Rules on electromagnetic compatibility (Uradni list RS, št. 39/16 in 9/20)
Rules on the first measurements and operational monitoring of the sources of electromagnetic
radiation and the terms of its implementation (Uradni list RS, št. 70/96, 41/04 – ZVO-1, 17/11 –
ZTZPUS-1 in 44/22 – ZVO-2)
Reference Title
EN 338 Structural timber - Strength classes
EN 1090-1+A1 Execution of steel structures and aluminium structures - Part 1:
Requirements for conformity assessment of structural components
EN 1090-2 Execution of steel structures and aluminium structures - Part 2: Technical
requirements for steel structures
EN 1991-1-4 Eurocode 1: Actions on structures - Part 1-4: General actions - Wind
actions
EN 1991-1-4:2005/A101:2008 Eurocode 1: Actions on structures - Part 1-4: General actions -
Wind actions - National annex
EN 1993-1-1:2005 Eurocode 3: Design of steel structures - Part 1-1: General rules and rules
for buildings
EN 1995-1-1 Eurocode 5: Design of timber structures - Part 1-1: General - Common
rules and rules for buildings
EN 1995-1-2 Eurocode 5: Design of timber structures - Part 1-2: General - Structural
fire design
EN 1997-1:2005 Eurocode 7: Geotechnical design - Part 1: General rules
EN 10025-1:2004 Hot rolled products of structural steels - Part 1: General technical delivery
conditions
EN 10025-2:2019 Hot rolled products of structural steels - Part 2: Technical delivery
conditions for non-alloy structural steels
EN 50182 Conductors for overhead lines - Round wire concentric lay stranded
conductors
EN 50183 Conductors for overhead lines - Aluminium-magnesium-silicon alloy wires
EN 50189 Conductors for overhead lines - Zinc coated steel wires
EN 50341-1:2012 Overhead electrical lines exceeding AC 1 kV - Part 1: General
requirements - Common specifications
EN 50443 Effects of electromagnetic interference on pipelines caused by high
voltage a.c. electric traction systems and/or high voltage a.c. power supply
systems
EN 50522:2011 Earthing of power installations exceeding 1 kV a.c.
EN 60071-1 Insulation co-ordination - Part 1: Definitions, principles and rules
EN 61232 Aluminium-clad steel wires for electrical purposes
EN 61284 Overhead lines - Requirements and tests for fittings
IEC/TR3 61597 Overhead electrical conductors - Calculation methods for stranded bare
conductors
EN ISO 898-1 Mechanical properties of fasteners made of carbon steel and alloy steel -
Part 1: Bolts, screws and studs with specified property classes - Coarse
thread and fine pitch thread (ISO 898-1)
2.2 Definitions
The definitions listed in EN 50341-1:2012 are supplemented and detailed for the purpose
of this Part 2-21 as follows:
2.2.110 Factor of ice load
Factor that determines the ice loading in a given geographical zone
2.3 Symbols
For the purpose of this Part of the Standard 2-21, the symbols listed in EN 50341-1:2012
shall be used and the following:
f the factor of ice load
zl
3. Basis of design
3.2 Requirements of overhead lines
3.2.2 Reliability requirements
(ncpt) SI.1 Reliability of overhead line
The minimum reliability level is 1 considering a 50-year return period and based on the
provisions of EN 50341-1:2012. Higher levels of reliability can be determined in the
project specification.
(ncpt) SI.2 Impact of wind on the temporary overhead lines
In accordance with SIST EN 1991-1-4:2005/A101:2008 for temporary overhead lines
should be considered seasonal coefficient c = 1,0
season
Slovenia 9/54 EN 50341-2-21:2023
(ncpt) SI.3 Impact of ice loads to the temporary overhead lines
When designing temporary overhead lines that route will take place in an area with the
altitude of less than 800 m and their use is foreseen between 1 June and 30 September,
then ice loads is not to be considered.
3.3 Limit states
3.3.1 General
(ncpt) SI.1 Simplified interpretation of limit states
Ultimate limit states shall be analysed when the mechanical properties of the support,
foundations, conductors, insulating chains and equipment are checked.
Factored values shall be used to determine the impact values.
Serviceability limit states shall be analysed when checking the supports, foundations,
conductors, insulator chains and equipment adoption. For example, checking support
deformations if they are within the limits of the permissible shift/buckling (polygonal
supports, concrete poles), the distance of the insulating chain to the structure is checked
due to wind influence, the sag controls, and so on.
Non-factored values shall be used to determine the impact values.
4. Actions on lines
4.1 Introduction
(ncpt) SI.1 Selection of the method
For assessing weather data in determining the numerical values of actions, approach 1
shall be used for wind loads, which provides for the application of European and national
standards to reference data, such as the basic wind speed set out in the national
appendix to EN 1991-1-4 and applied together with the provisions in chapter 4.
For the assessment of the ice loads, shall be used approach 3, which is based on the
use of data identified by a long and successful history of the design of overhead lines.
4.2 Permanent loads
(ncpt) SI.1 Self-weight of other equipment on the support
The self-weight of the other equipment intended to be fitted to the support acts as a
constant weight.
4.3 Wind loads
4.3.1 Field of application and basic wind velocity
(A-dev) SI.1 Basic wind speed, v
b,0
Basic wind velocity v is defined according to EN 1991-1-4. On the territory of Slovenia,
b,0
the zones for the basic values of wind velocity v are defined according to Figure
b,0
4.3/SI.1.
WIND VELOCITY FOR DESIGNING
Figure 4.3/SI.1: Zones for basic wind velocity values v ,
b 0
(source: SIST EN 1991-1-4:2005/A101:2008)
In zone 1, shell be considered a velocity of 20 m/s up to an altitude of 800 m, 25 m/s for
altitude between 800 and 1 600 m, 30 m/s for altitude between 1 600 m and 2 000 m and
above 30 m/s (e.g. 40 m/s) for an altitude above 2 000 m.
In zone 2, shell be considered a velocity of 25 m/s. It covers the fen area under the
Kamniško-Savinjske Alps and the Trnovski gozd area as well as area of Notranjska. For
altitudes between 1 600 m and 2 000 m, the project velocity value shall be 30 m/s and
above 2 000 m above 30 m/s (e.g. 40 m/s).
In zone 3, shell be considered a velocity of 30 m/s. It covers the areas of Primorje, the
Karst and part of the Vipava Valley.
4.3.2 Mean wind velocity
(ncpt) SI.1 Wind directional factor, c
dir
The value of the wind orientation factor c is assumed to be 1.0.
dir
(ncpt) SI.2 Consider of terrain categories
For overhead lines above 45 kV, category II shall be considered unless otherwise
specified in the project specification.
For overhead lines up to 45 kV, category II and III shall be considered unless otherwise
specified in the project specification.
The land roughness factor z and the land factor k shall be considered according to
0 r
Table 4.1 of EN 50341-1:2012.
(ncpt) SI.3 Orography factor, c
o
Slovenia 11/54 EN 50341-2-21:2023
Recommended value for the orography factor c is assumed to be 1.0.
o
4.3.3 Mean wind pressure
(ncpt) SI.1 Height and temperature effect
The effect of temperature and altitude on air density is not considered when calculating
the mean wind pressure. The calculations shall consider the conservative air density
value of q = 1.25 kg/m .
h
4.3.4 Turbulence intensity and peak wind pressure
(ncpt) SI.1 Peak pressure for lines not exceeding 45 kV
For lines with a voltage level up to 45 kV and a supports height of up to 15 m, the peak
pressure values shall be taken into account by zone and terrain category according to
Table 4.1/SI.1.
For lines with supports height above 15 m, the equation in SI.2 shall be considered.
Table 4.1/SI.1: Peak pressure for lines not exceeding 45 kV, in N/m
Land category
Wind loads
zones
II III
Zone 1 425 583
Zone 2 663 909
Zone 3 952 1305
(ncpt) SI.2 Calculation of peak pressure of wind for overhead lines over 45 kV
Peak wind pressure q (h) should be consider in accordance with EN 50341-1:2012.
p
4.4 Wind forces on overhead line components
4.4.1 Wind forces on conductors
4.4.1.1 General
(ncpt) SI.1 Reference height above ground
When calculating the wind force on conductors, the height of conductors or grounding
conductor mounted in the insulator chains, calculated using method 6 (mean arithmetic
height) in Table 4.3 of EN 50341-1:2012, shall be taken as the reference height.
4.4.1.2 Structural factor
(ncpt) SI.1 Span Factor for overhead lines above 45 kV
Span factor G shall be calculated in accordance with EN 50341-1:2012.
c
For peak factor value assumes to be k = 3.
p
For resonance response factor value should be taken R = 0.
(ncpt) SI.1 Span Factor for overhead lines up to 45 kV
Span factor G for supports up to 15 m height shall be consider as follows:
c
G =0.80 for terrain category II, and
c
G =0.75 for terrain category III.
c
For overhead lines with supports higher than 15 m, G should be calculate in accordance
c
with EN 50341-1-2012.
4.4.1.3 Drag Factor
(ncpt) SI.1 Drag factor for conductors of overhead lines up to 45 kV
For drag factor 𝐶𝐶 , the Table 4.2/SI.1 shell be used.
c
Table 4.2/SI.1: Drag Factor, Cc
Element of the overhead line C
c
Conductors with a diameter of up to 12.5 mm 1.2
Conductors with a diameter of 12.5 to 15.8 mm 1.1
Conductors with a diameter exceeding 15.8 mm 1.0
Non-round diameter conductors 1.3
Radar markers and flight warning spheres of a diameter between 300
0.4
mm and 1 000 mm
(ncpt) SI.2 Drag factor for conductors of overhead lines above 45 kV
For drag factor shell be used value 𝐶𝐶 = 1.0.
c
4.4.2 Wind loads on insulator sets
(ncpt) SI.1 Reference height of insulator set above the ground
As reference height of the insulator set should be consider the height of compression
point of the insulator to the support.
(ncpt) SI.2 Wind loads on insulator sets
The wind loads on insulator sets acts in direction of the wind action and is equal to
= q (h) ∙ G ∙ C ∙ A
QWins p ins ins ins
Where are:
q (h) peak wind pressure according to 4.3.4
p
Gins structural factor for insulator sets
C drag factor for insulator sets = 1.2
ins
A area of an insulator set exposed to the wind
ins
4.4.3 Wind forces on lattice towers
4.4.3.1 General
(ncpt) SI.1 Method selection
Method 1 shall be followed for the calculation of the wind force on the lattice towers. The
reference height of each section of the tower or of each element of the tower shall be the
height of the section of the geometric centre of gravity of the section of tower or element
above the ground.
4.4.3.2 Method 1
(ncpt) SI.1 Wind on tower body
The reference height h must be determined in accordance with 4.4.3.1/SI.1.
For the design factors for the support and consoles, the value Gt = Gtc = 1.0 shall be
taken into account.
Slovenia 13/54 EN 50341-2-21:2023
4.4.4 Wind forces on poles
(ncpt) SI.1 Method selection
Method 1 shell be used for the determination of the forces on single poles. The pole is
divided into sections and the reference height of each section is the height of the centre
of gravity of the section treated above ground. For the structural factor for poles is
recommended G = 1,0.
pol
4.5 Ice loads
4.5.1 General
(snc) SI.1 Ice loads zones
The ice loads depend on the geographical course of the overhead line. The provisions
for basic ice loads are based on long-standing experience (approach 3). For the purpose
of determining the ice loads for designing overhead lines, Slovenia is divided into three
zones:
1. Load ice zone: f = 1.6
zl
2. Load ice zone: f = 2.5
zl
3. Load ice zone: f = 5.0
zl
where is f the factor of ice load.
zl
Murska Sobota
Maribor
Dravograd
Ljutomer
Ptuj
Velenje
Celje
Kranj
Tolmin
Zidani most
Ljubljana
Krško
Nova Gorica
Novo mesto
1. cona
Postojna
2. cona
Kocevje
3. cona
Crnomelj
Koper
Figure 4.5.1/SI.1: Ice load factors are defined by geographical location in Slovenia.
st
zone includes areas where, on the basis of weather conditions and confirmed by
The 1
long years of experience, only small ice loads are produced which did not cause major
damage to overhead lines.
nd
The 2 zone includes areas where, on the basis of weather conditions, geographical
location and confirmed by many years of experience, high ice loads are expected to
cause damages to overhead lines.
rd
The 3 zone includes areas where, on the basis of weather conditions, geographical
location and confirmed by many years of experience, extremely high ice loads are
expected to caused major damage to the overhead lines.
The classification of the terrain of the overhead line or part of it into one of those zones
must be determined and justified by the investor in the project specification.
In particularly exposed areas, higher ice loads may be considered, if necessary, than
those stated for zone 3. This should be defined in the project specification.
For ice density (ρ ) shell be assumed value of 900 kg/m .
I
(snc) SI.2 A specialty for overhead lines up to 45 kV
In special cases, a factor of f may be used of less than 1.6, but not less than 1.0 to
zl
sizing the lines. This decision must be taken by the investor in the project specification.
For overhead lines with a voltage level ≤ 20 kV, a factor f of 1.0 may be used in zone 1
zl
and a factor f of 1,6 may be used in zone 2 and in zone 3 may be used a factor f = 2,5.
zl zl
This decision must be taken by the investor in the project specification.
(ncpt) SI.3 Ice thickness
The ice lining around the individual elements of the overhead line may be converted by
considering the thickness of the ice lining with a density of 900 kg/m and according to
the ice factor f :
zl
f = 1.0 ice lining with thickness 10 mm
zl
f = 1.6 ice lining with thickness 15 mm
zl
fzl = 2.5 ice lining with thickness 20 mm
f = 5.0 ice lining with thickness 30 mm
zl
4.5.2 Ice forces on conductors
(ncpt) SI.1 Ice forces on conductors
Ice loads on the length of the conductors is calculated according to:
I = f ∙ 1.8 ∙ √𝑑𝑑 [N/m]
zl
Where are:
f ice load factor, depends on the zone in accordance with 4.5.1/Sl.1
zl
d diameter of conductor (v mm)
(ncpt) SI.2 Ice forces on other elements of the overhead line
Ice loads on towers, insulator chains, warning balls, marking elements for birds and other
equipment shall not be considered, unless otherwise specified in the project
specification.
4.6 Combined wind and ice loads
4.6.1 Combined probabilities
(ncpt) SI.1 Combined probabilities of ice and wind
In Slovenia, the simultaneous action of ice and wind is considered as a combination of
the ice loads with the reducing wind loads.
Slovenia 15/54 EN 50341-2-21:2023
4.6.2 Drag factors and ice densities
(ncpt) SI.1 Drag factors and ice densities
In Slovenia shell be taken in account the ice density ρ = 900 kg/m . For the coefficient
I
of the ice shape shell be taken C = 1.0.
lc
In exceptional cases, it is permissible to require in the project specification lower ice
density or wet snow. In that case, the values given in Table 4.5 of EN 50341-1:2012 shall
be considered for the C coefficient.
lc
4.6.3 Mean wind pressure and peak wind pressure
(ncpt) SI.1 Peak wind pressure on iced conductors
For determination of the peak wind iced conductors shell be taken into account
4.6.1/SI.1.
4.6.6 Combination of wind velocities and ice loads
(ncpt) SI.1 Combination of wind velocities and ice loads
Wind force on the towers shall be calculated according to 4.4.3/SI.1, to the poles
according to 4.4.4/SI.1, to the insulator chains in accordance with 4.4.2/SI.1 and to the
iced conductors in accordance with 4.4.1/SI.1. This considers that the air pressure is
reduced to 40 % of the value.
4.6.6.1 Extreme ice load I combined with a high probability wind velocity V
T IH
(ncpt) SI.1 Iced conductors
The impact of wind on the iced conductors should be considered for all types of supports.
4.7 Temperature effects
(ncpt) SI.1 General
Temperature effects for overhead lines shell be considered in the following design
situations:
a) –20 °C the minimum temperature to be considered without wind and ice loads,
b) +5 °C the normal ambient reference temperature assumed at exceptional wind speed,
c) –5 °C temperature assumed at the formation of the ice lining,
d) –5 °C temperature to be considered when combining wind and ice,
e) +10 °C normal ambient reference temperature assumed at the time of windless.
4.8 Security loads
4.8.1 General
(ncpt) SI.1 General
Security loads are considered in 4.12.2/SI.1 (load cases H, J in K).
For overhead lines up to 45 kV load case K is not dealt with.
4.9 Safety loads
(ncpt) SI.1 Construction and maintenance loads
The loads arising from the construction and maintenance of overhead lines are referred
below as construction loads.
Vertical acting forces of at least 1.0 kN shall be assumed for crossarms of suspension
and angle suspension towers or poles and at least 2.0 kN for all other types of towers.
In the case of lattice steel structures these forces shell be assumed as acting at the
individually most unfavourable nodes of the lower chords of one crossarm face and in all
other cases in the axis of the crossarm at the attachment point of a conductor. For all
hiking elements which are inclined less than 45° towards the horizontal, a vertical force
of 1.0 kN in half of the element shall be assumed, however, without any other loads.
Climbing wedges must be checked at the statically unfavourable position of a
concentrated force of 1.0 kN.
4.9.1 Construction and maintenance loads
(ncpt) SI.1 Loads during construction and maintenance
Loads during construction and maintenance should be considered in accordance with
4.12.2/SI.1 and load case I
...
S L O V E N S K I SIST EN 50341-2-21
S T A N D A R D julij 2023
Nadzemni električni vodi za izmenične napetosti nad 1 kV –
Nacionalna normativna določila (NNA) za državo Slovenijo
(na podlagi EN 50341-1:2012)
Overhead electrical lines exceeding AC 1kV – National Normative Aspects (NNA)
for Slovenia (based on EN 50341-1:2012)
Referenčna oznaka
ICS 29.240.20 SIST EN 50341-2-21:2023 (sl)
Nadaljevanje na straneh II do IV in od 1 do 57
2023-11. Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno.
SIST EN 50341-2-21 : 2023
NACIONALNI UVOD
Standard SIST EN 50341-2-21 (sl), Nadzemni električni vodi za izmenične napetosti nad 1 kV –
Nacionalna normativna določila (NNA) za državo Slovenijo (na podlagi EN 50341-1:2012)), 2023, ima
status slovenskega standarda in je istoveten evropskemu standardu EN 50341-2-21 (en), Overhead
electrical lines exceeding AC 1 kV – National Normative Aspects (NNA) for Slovenia (based on EN
50341-1:2012), 2023.
NACIONALNI PREDGOVOR
Slovenski standard SIST EN 50341-2-21:2023 je pripravil tehnični odbor SIST/TC NVV Nadzemni vodi
in vodniki.
Tehnični odbor Evropske organizacije za standardizacijo v elektrotehniki CLC/TC 11 je pripravil evropski
standard EN 50341-2-21:2023, Overhead electrical lines exceeding AC 1 kV – National Normative
Aspects (NNA) for Slovenia (based on EN 50341-1:2012), ki je v sistem slovenske nacionalne
standardizacije privzet kot SIST EN 50341-2:21:2023, Nadzemni električni vodi za izmenične napetosti
nad 1 kV – Nacionalna normativna določila (NNA) za državo Slovenijo (na podlagi EN 50341-1:2012).
Ker je mnogo parametrov projektiranja nadzemnih električnih vodov v posameznih državah članicah
Evropske unije pogojenih geoklimatsko in zgodovinsko, se je tehnični odbor CLC/TC 11 odločil, da v
prvi del standarda vključi le osnovne parametre, ki jih morajo vse države članice upoštevati, da
zagotovijo ustrezno varnost nadzemnih električnih vodov na celotnem območju EU. Dodatno pa je
tehnični odbor določil, da mora vsaka država članica zbrati vsa posebna in dodatna določila, ki so
specifična zanjo pri projektiranju nadzemnih električnih vodov. Določena sta bila postopek priprave teh
dokumentov in njegova oblika. Prav tako so bile določene zaporedne številke delov nacionalnih
normativnih določil za vsako državo članico, za Slovenijo je to oznaka EN 50341-2-21.
Za vsako posamezno državo velja, da je del z njenimi lastnimi nacionalnimi določili zanjo normativen,
deli ostalih držav pa so informativni. Vsi deli so že ali še bodo po njihovi pripravi v predpisanih rokih
privzeti v sistem evropske standardizacije.
Priprava slovenskih nacionalnih normativnih določil se je začela hkrati s privzemom evropskega
standarda EN 50341-1:2012 v slovenskem tehničnem odboru SIST/TC NVV Nadzemni vodi in vodniki.
To obsežno in strokovno izredno zahtevno delo je poleg strokovnjakov s področja elektrotehnike
zahtevalo tudi sodelovanje kompetentnih strokovnjakov s področij gradbeništva in meteorologije.
Pri pripravi slovenskega standarda SIST EN 50341-2-21:2023 je tehnični odbor SIST/TC NVV
Nadzemni vodi in vodniki upošteval vsa pravila in navodila, ki jih je za pripravo nacionalnih normativnih
določil pripravil evropski tehnični odbor CLC/TC 11, ter izkušnje strokovnjakov v drugih državah
članicah. Tehnični odbor SIST/TC NVV se je v tem času aktivno vključil v delo evropskega tehničnega
odbora CLC/TC 11. Da je naloga obsežna, so ugotavljali strokovnjaki tudi v ostalih državah članicah.
Odločitev za izdajo tega standarda je 20. novembra 2023 sprejel tehnični odbor SIST/TC NVV Nadzemni
vodi in vodniki.
ZVEZE S STANDARDI
S privzemom tega evropskega standarda veljajo za omejeni namen referenčnih standardov vsi
standardi, navedeni v izvirniku, razen tistih, ki so že sprejeti v nacionalno standardizacijo:
SIST EN 338 Konstrukcijski les – Trdnostni razredi
SIST EN 1090-1+A1 Izvedba jeklenih in aluminijastih konstrukcij – 1. del: Zahteve za
ugotavljanje skladnosti sestavnih delov konstrukcij
SIST EN 1090-2 Izvedba jeklenih in aluminijastih konstrukcij – 2. del: Tehnične zahteve za
izvedbo jeklenih konstrukcij
SIST EN 1991-1-4 Evrokod 1: Vplivi na konstrukcije – 1-4. del: Splošni vplivi – Obtežbe vetra
II
SIST EN 50341-2-21 : 2023
SIST EN 1991-1-4:2005/A101:2008 Evrokod 1: Vplivi na konstrukcije – 1-4. del: Splošni vplivi –
Obtežbe vetra – Nacionalni dodatek
SIST EN 1993-1-1:2005 Evrokod 3: Projektiranje jeklenih konstrukcij – 1-1. del: Splošna pravila in
pravila za stavbe
SIST EN 1995-1-1 Evrokod 5: Projektiranje lesenih konstrukcij – 1-1. del: Splošna pravila in
pravila za stavbe
SIST EN 1995-1-2 Evrokod 5: Projektiranje lesenih konstrukcij – 1-2. del: Splošna pravila –
Projektiranje požarnovarnih konstrukcij
SIST EN 1997-1:2005 Evrokod 7: Geotehnično projektiranje – 1. del: Splošna pravila
SIST EN 10025-1:2004 Vroče valjani izdelki iz konstrukcijskih jekel – 1. del: Splošni tehnični
dobavni pogoji
SIST EN 10025-2:2019 Vroče valjani izdelki iz konstrukcijskih jekel – 2. del: Tehnični dobavni
pogoji za nelegirana konstrukcijska jekla
SIST EN 50182 Vodniki za nadzemne vode – Vrvi iz koncentrično sukanih okroglih žic
SIST EN 50183 Vodniki za nadzemne vode – Žice iz zlitine aluminij-magnezij-silicij
SIST EN 50189 Vodniki za nadzemne vode – Pocinkana jeklena žica
SIST EN 50341-1:2013 Nadzemni električni vodi za izmenične napetosti nad 1 kV – 1. del: Splošne
zahteve – Skupna določila
SIST EN 50443 Učinki elektromagnetne interference na cevovode, ki jih povzročajo
visokonapetostni sistemi izmeničnega toka električne vleke in/ali
visokonapetostni izmenični napajalni sistemi
SIST EN 50522:2011 Ozemljitev elektroenergetskih postrojev, ki presegajo 1 kV izmenične
napetosti
SIST EN 60071-1 Koordinacija izolacije – 1. del: Definicije, načela in pravila
SIST EN 61232 Z aluminijem oplaščene jeklene žice za elektrotehnične namene
SIST EN 61284 Nadzemni vodi – Zahteve in preskusi za obesno opremo (IEC 61284)
SIST IEC/TR3 61597 Vodniki za nadzemne vode – Izračuni za gole pletene vrvi
SIST EN ISO 898-1 Mehanske lastnosti veznih elementov iz ogljikovega in legiranega jekla –
1. del: Vijaki s specificiranim trdnostnim razredom – Grobi in fini navoj
(ISO 898-1:2013)
OSNOVA ZA IZDAJO STANDARDA
– privzem standarda EN 50341-2-21:2023
PREDHODNA IZDAJA
– SIST EN 50341-3-21:2009, Nadzemni električni vodi za izmenične napetosti nad 45 kV –
3-21. del: Nacionalna normativna določila (NNA) za Slovenijo (na podlagi SIST EN 50341-1:2002)
III
SIST EN 50341-2-21 : 2023
OPOMBA
– Povsod, kjer se v besedilu standarda uporablja izraz ''evropski standard'', v SIST EN 50341-2-
21:2023 to pomeni ''slovenski standard''.
– Nacionalni uvod in nacionalni predgovor nista sestavni del standarda.
– Ta nacionalni dokument je istoveten EN 50341-2-21:2023 in je objavljen z dovoljenjem
CEN-CENELEC
Upravni center
Rue de la Science 23
B-1040 Bruselj
This national document is identical with EN 50341-2-21:2023 and is published with the permission
of
CEN-CENELEC
Management Centre
Rue de la Science 23
B-1040 Brussels
IV
EVROPSKI STANDARD EN 50341-2-21
EUROPEAN STANDARD
NORME EUROPÉENNE
julij 2023
EUROPÄISCHE NORM
ICS 29.240.20
Slovenska izdaja
Nadzemni električni vodi za izmenične napetosti nad 1 kV –
Nacionalna normativna določila (NNA) za državo Slovenijo
(na podlagi EN 50341-1:2012)
Ta evropski standard je CENELEC sprejel 31. maja 2023. Člani CEN morajo izpolnjevati notranje
predpise CEN/CENELEC, ki določajo pogoje, pod katerimi dobi ta evropski standard status
nacionalnega standarda brez kakršnihkoli sprememb.
Sezname najnovejših izdaj teh nacionalnih standardov in njihove bibliografske podatke je mogoče na
zahtevo dobiti pri Upravnem centru CEN-CENELEC ali pri članih CENELEC.
Ta evropski standard obstaja v treh uradnih izdajah (angleški, francoski in nemški). Izdaje v drugih
jezikih, ki jih člani CENELEC na lastno odgovornost prevedejo in izdajo ter priglasijo pri Upravnem
centru CEN-CENELEC, veljajo kot uradne izdaje.
Člani CENELEC so nacionalni organi za standarde Avstrije, Belgije, Bolgarije, Cipra, Češke republike,
Danske, Estonije, Finske, Francije, Grčije, Hrvaške, Irske, Islandije, Italije, Latvije, Litve, Luksemburga,
Madžarske, Malte, Nemčije, Nizozemske, Norveške, Poljske, Portugalske, Republike Severne
Makedonije, Romunije, Slovaške, Slovenije, Srbije, Španije, Švedske, Švice, Turčije in Združenega
kraljestva.
CENELEC
Evropski komite za standardizacijo v elektrotehniki
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Upravni center CEN-CENELEC: Rue de la Science 23, B-1040 Bruselj
© 2023 CENELEC Vse pravice do izkoriščanja v kakršnikoli obliki in na kakršenkoli Ref. oznaka EN 50341-2-21:2023 E
način imajo nacionalni člani CENELEC.
SIST EN 50341-2-21 : 2023
VSEBINA Stran
Evropski predgovor . 6
1 Področje uporabe . 7
2 Zveze s standardi in predpisi, definicije in simboli . 7
2.1 Zveze s standardi in predpisi . 7
2.2 Definicije . 9
2.3 Simboli . 9
3 Osnove projektiranja . 9
3.2 Zahteve za nadzemne vode . 9
3.2.2 Zanesljivost nadzemnih vodov . 9
3.3 Mejna stanja . 9
3.3.1 Splošno . 9
4 Vplivi na nadzemne vode .10
4.1 Uvod .10
4.2 Stalne obtežbe .10
4.3 Obtežbe vetra .10
4.3.1 Področje uporabe in osnovna hitrost vetra .10
4.3.2 Srednja hitrost vetra .11
4.3.3 Srednji tlak vetra .12
4.3.4 Jakost turbulence in konični tlak vetra.12
4.4 Sile vetra na komponente nadzemnega voda .12
4.4.1 Sile vetra na vodnike .12
4.4.2 Obtežbe vetra na izolatorske verige .13
4.4.3 Sile vetra na palične stebre .14
4.4.4 Sile vetra na drogove.14
4.5 Obtežbe žleda .14
4.5.1 Splošno .14
4.5.2 Sile žleda na vodnike .16
4.6 Kombinacija obtežb vetra in žleda .16
4.6.1 Verjetnost kombinacij .16
4.6.2 Faktor zračnega upora in gostote žleda .16
4.6.3 Srednji in konični tlak vetra .16
4.6.6 Kombinacija hitrosti vetra in obtežb žleda .17
4.7 Temperaturni vplivi .17
4.8 Obtežbe z vidika obratovalne sigurnosti .17
4.8.1 Splošno .17
4.9 Varnostne obtežbe .17
4.9.1 Obtežbe pri gradnji in vzdrževanju .………………………………………………………………18
4.10 Sile zaradi kratkostičnih tokov ………………………………………………………………………… 18
4.11 Druge posebne sile.18
SIST EN 50341-2-21 : 2023
4.11.1 Plazovi, drseči sneg . 18
4.11.2 Potresi . 18
4.12 Primeri obtežb .18
4.12.1 Splošno .18
4.12.2 Standardni primeri obtežb .20
4.13 Delni faktorji za vplive .23
5 Električne zahteve .24
5.2 Toki .24
5.2.1 Normalni tok .24
5.3 Koordinacija izolacije .24
5.4 Razvrstitev napetosti in prenapetosti .25
5.4.2 Značilne napetosti omrežne frekvence.25
5.4.5 Značilne prenapetosti s strmim čelom .25
5.5 Najkrajše zračne izolacijske razdalje za izogibanje preskokom .26
5.5.3 Empirične metode, osnovane na evropskih izkušnjah .26
5.6 Primeri obtežb za izračun izolacijskih razdalj .27
5.6.2 Najvišja temperatura vodnika .27
5.6.3 Obtežbe vetra za določitev električnih izolacijskih razdalj.27
5.6.4 Obtežbe žleda za določitev električnih izolacijskih razdalj .28
5.6.5 Kombinirane obtežbe vetra in žleda .29
5.8 Notranje izolacijske razdalje v razpetini in v glavi podpore .29
5.9 Zunanje izolacijske razdalje .31
5.9.1 Splošno .31
5.9.2 Zunanje izolacijske razdalje do tal na območjih, daleč od stavb, cest, plovnih poti itd. .32
5.9.3 Zunanje izolacijske razdalje do stanovanjskih stavb in drugih zgradb .32
5.9.4 Zunanje izolacijske razdalje do križanja prometne poti .33
5.9.5 Zunanje izolacijske razdalje do bližnjih prometnih poti .34
5.9.6 Zunanje izolacijske razdalje do drugih nadzemnih elektroenergetskih vodov ali
nadzemnih telekomunikacijskih vodov .34
5.9.7 Zunanje izolacijske razdalje do rekreacijskih površin (igrišča, športna območja itd.) .35
5.10 Učinek korone .36
5.10.1 Radiofrekvenčni šum .36
5.10.2 Slišni (koronski) hrup . 36
5.11 Električna in magnetna polja .36
5.11.1 Električna in magnetna polja pod nadzemnim vodom .36
5.11.2 Indukcija zaradi električnih in magnetnih polj .37
5.11.3 Motenje telekomunikacijskih tokokrogov .37
6 Ozemljitveni sistemi .37
6.1 Uvod .37
6.1.3 Ozemljitveni ukrepi proti vplivom udarov strel .37
6.1.4 Preneseni potenciali .38
SIST EN 50341-2-21 : 2023
6.3 Dimenzioniranje glede na toplotno odpornost .39
6.3.2 Izračun glede na tok .39
6.4 Dimenzioniranje glede na varnost ljudi.39
6.4.2 Mejne vrednosti napetosti dotika na različnih lokacijah .39
6.5 Nadzor ozemljitvenih sistemov na terenu in dokumentacija .39
7 Podpore .40
7.1 Uvodna projektna določila .40
7.2 Materiali .40
7.2.1 Jekla, vijaki, matice in podložke, varilni material .40
7.3 Jekleni palični stebri .41
7.3.1 Splošno .41
7.3.5 Analiza konstrukcije .41
7.3.6 Mejna stanja nosilnosti .41
7.3.8 Nosilnost spojev .41
7.4 Jekleni drogovi .42
7.4.1 Splošno .42
7.4.7 Mejna stanja uporabnosti (EN 1993-1-1:2005, točka 7) .42
7.4.8 Nosilnost spojev .43
7.5 Leseni drogovi .43
7.5.3 Materiali .43
7.5.5 Mejno stanje nosilnosti .43
7.5.7 Nosilnost spojev .44
7.6 Betonski drogovi .44
7.9 Korozijska zaščita in končna obdelava.45
7.9.1 Splošno .45
7.10 Pripomočki za vzdrževanje .45
7.10.1 Plezanje .45
7.10.2 Vzdrževalnost .46
8 Temelji .46
8.1 Uvod .46
8.2 Osnove geotehničnega projektiranja (EN 1997-1:2004, točka 2) .46
8.2.2 Geotehnično projektiranje z izračunom .46
9 Vodniki in zaščitne vrvi .48
9.2 Aluminijasti vodniki .48
9.2.1 Značilnosti in mere .48
9.2.3 Obratovalna temperatura vodnikov in lastnosti masti .48
9.3 Jekleni vodniki ……………………………………………………………………………………………. 49
9.3.3 Obratovalna temperatura vodnikov in lastnosti masti ……………………………………………… 49
9.6 Splošne zahteve . 49
9.6.2 Delni faktorji za vodnike . 49
10 Izolatorji .50
SIST EN 50341-2-21 : 2023
10.2 Standardne električne zahteve .50
10.7 Mehanske zahteve .50
10.9 Izbira materiala in specifikacija .51
11 Pribor za nadzemne vode .51
11.2 Električne zahteve .51
11.5 Zahteve glede kratkostičnega toka in obloka .52
11.6 Mehanske zahteve .52
12 Zagotavljanje kakovosti, pregledi in prevzemi .53
Dodatek G (normativni): Računske metode za ozemljitvene sisteme .54
G.4 Napetost dotika in tok skozi telo .54
G.4.1 Soodvisnost med tokom skozi telo in napetostjo dotika .54
Dodatek J (normativni): Kotniki v jeklenih paličnih stebrih .55
J.4 Uklonska nosilnost kotnikov pri tlačni obremenitvi (glej 7.3.6.4 v EN 50341-1:2012) .55
J.4.1 Upogibna uklonska nosilnost .55
J.4.3 Vitkost elementov .55
Dodatek M (informativni): Geotehnično in konstrukcijsko projektiranje temeljev .56
M.3 Vzorčni primer delno empiričnih modelov za ocenjevanje nosilnosti .56
M.3.1 Geotehnično projektiranje z izračunom .56
M.3.1.2 Blok temelji .57
SIST EN 50341-2-21 : 2023
Evropski predgovor
Naslednje točke od 1 do 6 so napisane po zahtevah tehničnega odbora CLC/TC 11 in so obvezne za
vse nacionalne posebnosti (NNA).
1) Naslov slovenskega tehničnega odbora SIST/TC NVV Nadzemni vodi in vodniki je:
Slovenski inštitut za standardizacijo (SIST)
Ulica gledališča BTC 2
SI-1000 Ljubljana, Slovenija
Telefon: 00 386 1 478 30 13
E-pošta: sist@sist.si
Naziv ustreznega tehničnega organa: SIST/TC NVV Tehnični odbor za nadzemne vode in vodnike.
2) Slovenski nacionalni tehnični odbor SIST/TC NVV je z vso odgovornostjo pripravil ta standard, ki
je drugi del standarda EN 50341-1 in vključuje slovenske nacionalne normativne vidike (NNA).
Dokument je bil preverjen po postopkih CENELEC in tehničnega odbora CLC/TC 11.
OPOMBA: Slovenski tehnični odbor SIST/TC NVV prevzema vso odgovornost za tehnično pravilno uskladitev tega
standarda EN 50341-2-21:2023 s standardom EN 50341-1:2012. Izvedeni so bili vsi potrebni pregledi za
zagotavljanje/obvladovanje kakovosti. Vendar pa je treba opozoriti, da je bil ta nadzor kakovosti izveden v
okviru splošne odgovornosti odbora za standard v skladu z nacionalnimi predpisi.
3) Ta EN 50341-2-21 (v nadaljevanju del 2-21) je normativen za uporabo v Sloveniji in informativen
za druge države.
4) Ta EN 50341-2-21 je treba brati skupaj s prvim delom (EN 50341-1). Številčenje točk v tem delu
standarda ustreza številčenju iz prvega dela. Posebne podtočke s predpono "SI" je treba brati kot
dopolnilo k ustreznemu besedilu iz prvega dela. Kakršnokoli potrebno pojasnilo o uporabi tega
dokumenta v povezavi s prvim delom je treba predložiti slovenskemu tehničnemu odboru SIST/TC
NVV, ki bo v sodelovanju z evropskim tehničnim odborom CLC/TC 11 pojasnil zahteve.
Kadar v tem standardu ni sklicevanja na posamezne podtočke iz prvega dela, potem velja besedilo
iz prvega dela.
5) V primeru "okvirjenih vrednosti", ki so opredeljene v prvem delu, je treba v Sloveniji upoštevati
spremenjene vrednosti (če obstajajo), opredeljene v tem drugem delu.
Vendar, katerakoli "okvirjena vrednost", bodisi v prvem delu ali v tem drugem delu, se ne sme
spremeniti, če obstajajo večja tveganja v projektni specifikaciji.
6) Slovenski nacionalni standardi in predpisi, ki urejajo nadzemne električne vode nad 1 kV izmenične
napetosti, so navedeni v točki 2.1 tega standarda (2.1/SI.1).
OPOMBA: Vse nacionalne standarde, navedene v tem standardu, bodo zamenjali ustrezni evropski standardi takoj, ko
bodo na voljo in jih bo sprejel slovenski organ za standarde, kar bo treba poročati sekretarju tehničnega
odbora CLC/TC 11.
SIST EN 50341-2-21 : 2023
1 Področje uporabe
1.1 Splošno
(A-dev) SI.1 Definicija novega nadzemnega električnega voda
Nov nadzemni električni vod je opredeljen kot vod, ki predstavlja funkcionalno zaključeno celoto
za prenos električne energije med točkama A in B (to pomeni novogradnjo vseh podpor s temelji,
vodnikov z izolatorji in obesno opremo ter sistemi ozemljitve).
Objekti, ki se v času izdaje standarda projektirajo (začetek izdelave projekta za pridobitev
gradbenega dovoljenja) ali gradijo, se lahko zaključijo v skladu s standardi, ki so bili veljavni ob
začetku projektiranja ali gradnje nadzemnega voda.
Pri vzdrževalnih in obnovitvenih delih z večjimi konstrukcijskimi spremembami nadzemnega
voda je treba ta standard uporabiti skladno z določili projektne naloge. Npr., pri gradnji nove
podpore na novih temeljih v trasi obstoječega voda je treba za podporo in temelje uporabiti
določila tega standarda, za ostale elemente napenjalnega polja pa določil tega standarda ni
treba upoštevati.
Pri projektiranju in gradnji nadzemnih vodov enosmerne napetosti so zahteve iz tega standarda
uporabne tudi pri oblikovanju konstrukcij, vendar ne za električne zahteve, ki jih je treba določiti
v projektni nalogi.
1.2 Področje uporabe
(ncpt) SI.1 Vodniki z optičnimi vlakni
Ta standard se uporablja tudi za projektiranje in gradnjo vodnikov z vgrajenimi optičnimi vlakni
(OPPC), zaščitnih vrvi z vgrajenimi optičnimi vlakni (OPGW) in dielektričnih samonosnih kablov
(ADSS).
(ncpt) SI.2 Uporaba oplaščenih vodnikov in nadzemna izolirana kabelska omrežja
Za nadzemne vode z oplaščenimi vodniki, izoliranimi z umetno maso, in za nadzemna izolirana
kabelska omrežja do vključno 45 kV je treba projektne zahteve opredeliti v projektni nalogi.
(ncpt) SI.3 Uporaba za vgradnjo ostale opreme na podpore
Ta standard se uporablja tudi za vso ostalo opremo, predvideno za vgradnjo na novo podporo
nadzemnega voda. Za ostalo opremo je treba šteti vso tisto opremo, ki ne pripada osnovnim
elementom nadzemnega voda, npr. opremo za prehod nadzemnega voda v kabel, ločilnike,
telekomunikacijsko opremo, meteorološko opremo, merilno opremo in drugo. Izvesti je treba
statično preverjanje podpore in temelja nadzemnega voda zaradi vpliva lastne teže ostale
opreme ter vpliva vetra in žleda na ostalo opremo.
2 Zveze s standardi in predpisi, definicije in simboli
2.1 Zveze s standardi in predpisi
Vsi standardi, na katere se sklicuje besedilo tega standarda, so navedeni v EN 50341-1:2012.
Poleg navedenih standardov je pri projektiranju in gradnji nadzemnih vodov nad 1 kV v Sloveniji
treba upoštevati veljavno nacionalno zakonodajo in predpise, povezane z umeščanjem v prostor
ter varnostjo in kakovostjo.
(A-dev) SI.1 Nacionalni normativni akti in predpisi, ki jih je treba upoštevati pri projektiranju in gradnji
nadzemnih vodov v Sloveniji so:
Energetski zakon (Uradni list RS, št. 60/19, 65/20, 158/20 – ZURE, 121/21 – ZSROVE, 172/21
– ZOEE, 204/21 – ZOP in 44/22 – ZOTDS)
SIST EN 50341-2-21 : 2023
Gradbeni zakon (Uradni list RS, št. 199/21 in 105/22 – ZZNŠPP)
Pravilnik o tehničnih normativih za graditev nadzemnih elektroenergetskih vodov z nazivno
napetostjo od 1 KV do 400 kV (Uradni list RS, št. 52/14 in 67/22)
Zakon o prostorskem načrtovanju (Uradni list RS, št. 33/07, 70/08 – ZVO-1B, 108/09, 80/10 –
ZUPUDPP, 43/11 – ZKZ-C, 57/12, 57/12 – ZUPUDPP-A, 109/12, 76/14 – odl. US, 14/15 –
ZUUJFO, 61/17 – ZUreP-2 in 199/21 – ZUreP-3)
Uredba o hrupu v naravnem in življenjskem okolju (Uradni list RS, št. 121/04, 59/19, 44/22 –
ZVO-2 in 53/22)
Odlok o strategiji prostorskega razvoja Slovenije (Uradni list RS, št. 199/21)
Pravilnik o elektromagnetni združljivosti (Uradni list RS, št. 39/16 in 9/20)
Pravilnik o prvih meritvah in obratovalnem monitoringu za vire elektromagnetnega sevanja ter
o pogojih za njihovo izvajanje (Uradni list RS, št. 70/96, 41/04 – ZVO-1, 17/11 – ZTZPUS-1 in
44/22 – ZVO-2)
Zveza s standardi Naslov
EN 338 Konstrukcijski les – Trdnostni razredi
EN 1090-1+A1 Izvedba jeklenih in aluminijastih konstrukcij – 1. del: Zahteve za
ugotavljanje skladnosti sestavnih delov konstrukcij
EN 1090-2 Izvedba jeklenih in aluminijastih konstrukcij – 2. del: Tehnične zahteve za
izvedbo jeklenih konstrukcij
EN 1991-1-4 Evrokod 1: Vplivi na konstrukcije – 1-4. del: Splošni vplivi – Obtežbe vetra
EN 1991-1-4:2005/A101:2008 Evrokod 1: Vplivi na konstrukcije – 1-4. del: Splošni vplivi –
Obtežbe vetra – Nacionalni dodatek
EN 1993-1-1:2005 Evrokod 3: Projektiranje jeklenih konstrukcij – 1-1. del: Splošna pravila in
pravila za stavbe
EN 1995-1-1 Evrokod 5: Projektiranje lesenih konstrukcij – 1-1. del: Splošna pravila in
pravila za stavbe
EN 1995-1-2 Evrokod 5: Projektiranje lesenih konstrukcij – 1-2. del: Splošna pravila –
Projektiranje požarnovarnih konstrukcij
EN 1997-1:2005 Evrokod 7: Geotehnično projektiranje – 1. del: Splošna pravila
EN 10025-1:2004 Vroče valjani izdelki iz konstrukcijskih jekel – 1. del: Splošni tehnični
dobavni pogoji
EN 10025-2:2019 Vroče valjani izdelki iz konstrukcijskih jekel – 2. del: Tehnični dobavni
pogoji za nelegirana konstrukcijska jekla
EN 50182 Vodniki za nadzemne vode – Vrvi iz koncentrično sukanih okroglih žic
EN 50183 Vodniki za nadzemne vode – Žice iz zlitine aluminij-magnezij-silicij
EN 50189 Vodniki za nadzemne vode – Pocinkana jeklena žica
EN 50341-1:2012 Nadzemni električni vodi za izmenične napetosti nad 1 kV – 1. del:
Splošne zahteve – Skupna določila
EN 50443 Učinki elektromagnetne interference na cevovode, ki jih povzročajo
visokonapetostni sistemi izmeničnega toka električne vleke in/ali
visokonapetostni izmenični napajalni sistemi
EN 50522:2011 Ozemljitev elektroenergetskih postrojev, ki presegajo 1 kV izmenične
napetosti
SIST EN 50341-2-21 : 2023
EN 60071-1 Koordinacija izolacije – 1. del: Definicije, načela in pravila
EN 61232 Z aluminijem oplaščene jeklene žice za elektrotehnične namene
EN 61284 Nadzemni vodi – Zahteve in preskusi za obesno opremo (IEC 61284)
IEC/TR3 61597 Vodniki za nadzemne vode – Izračuni za gole pletene vrvi
EN ISO 898-1 Mehanske lastnosti veznih elementov iz ogljikovega in legiranega jekla –
1. del: Vijaki s specificiranim trdnostnim razredom – Grobi in fini navoj
(ISO 898-1:2013)
2.2 Definicije
V tem delu standarda se uporabljajo definicije, navedene v EN 50341-1:2012, in naslednja:
2.2.110 faktor obtežbe žleda
faktor, ki določa obtežbe žleda vodnikov v določeni geografski coni
2.3 Simboli
V tem delu standarda 2-21 se uporabljajo simboli, navedeni v EN 50341-1:2012, in naslednji:
f faktor obtežbe žleda
zl
3 Osnove projektiranja
3.2 Zahteve za nadzemne vode
3.2.2 Zanesljivost nadzemnih vodov
(ncpt) SI.1 Zanesljivost nadzemnega voda
Upoštevajoč določila EN 50341-1:2012 in pretekle izkušnje je določena minimalna stopnja
zanesljivosti 1 s 50-letno povratno dobo. Višje stopnje zanesljivosti se lahko določijo v projektni
nalogi.
(ncpt) SI.2 Vpliv vetra na začasne nadzemne vode
V skladu s SIST EN 1991-1-4:2005/A101:2008 naj se za začasne vode privzame faktor sezonski
koeficient c = 1,0.
season
(ncpt) SI.3 Vpliv obtežb žleda na začasne nadzemne vode
Pri projektiranju začasnih nadzemnih vodov, ki bodo potekali na območju z nadmorsko višino,
nižjo od 800 m, in je njihova uporaba predvidena v obdobju med 1. junijem in 30. septembrom,
se obtežbe zaradi žleda ne upoštevajo.
3.3 Mejna stanja
3.3.1 Splošno
(ncpt) SI.1 Poenostavljena razlaga mejnih stanj
Mejno stanje nosilnosti (MSN) je treba uporabiti pri preverjanju mehanskih lastnosti podpor,
temeljev, vodnikov, izolatorskih verig in opreme.
Za določitev vrednosti vplivov je treba uporabiti faktorirane vrednosti.
SIST EN 50341-2-21 : 2023
Mejno stanje uporabnosti (MSU) je treba uporabiti pri preverjanju uporabnosti podpor, temeljev,
vodnikov, izolatorskih verig in opreme. Na primer pri preverjanju deformacij podpor, da so v
mejah dovoljenih pomikov/zasukov (poligonalni stebri, betonski drogovi), pri preverjanje razdalje
izolatorske verige do konstrukcije zaradi vpliva vetra, pri preverjanju povesov itn.
Za določitev vrednosti vplivov je treba uporabiti nefaktorirane vrednosti.
4 Vplivi na nadzemne vode
4.1 Uvod
(ncpt) SI.1 Izbor metode
Za ocenjevanje vremenskih podatkov pri ugotavljanju številskih vrednosti vplivov je treba pri
obtežbah vetra uporabiti pristop 1, ki predvideva uporabo evropskih in nacionalnih standardov
za referenčne podatke, kot je npr. osnovna hitrost vetra, določena v nacionalnem dodatku k EN
1991-1-4 in se uporablja skupaj z določili v točki 4.
Za ocenjevanje obtežb žleda je treba upoštevati pristop 3, ki temelji na uporabi podatkov,
ugotovljenih z dolgo in uspešno zgodovino projektiranja nadzemnih vodov.
4.2 Stalne obtežbe
(ncpt) SI.1 Lastna teža ostale opreme na stebru
Lastna teža ostale opreme, predvidene za vgradnjo na steber, deluje kot stalna obtežba.
4.3 Obtežbe vetra
4.3.1 Področje uporabe in osnovna hitrost vetra
(A-dev) SI.1 Osnovna hitrost vetra, v
b,0
Osnovna hitrost vetra vb,0 je definirana skladno z EN 1991-1-4. Na ozemlju Slovenije so cone
za osnovne vrednosti hitrosti vetra v opredeljene skladno s sliko 4.3.1/SI.1.
b,0
SIST EN 50341-2-21 : 2023
PROJEKTNA HITROST VETRA
Slika 4.3.1/SI.1: Cone za osnovne vrednosti hitrosti vetra v
b,0
(vir: SIST EN 1991-1-4:2005/A101:2008)
V coni 1 je treba upoštevati hitrost 20 m/s do nadmorske višine 800 m, 25 m/s za nadmorsko
višino med 800 m in 1 600 m, 30 m/s za nadmorsko višino med 1 600 m in 2 000 m ter nad
30 m/s (npr. 40 m/s) za nadmorsko višino nad 2 000 m.
V coni 2 je treba upoštevati hitrost 25 m/s. Zajema območje fena pod Kamniško-Savinjskimi
Alpami ter območje Trnovskega gozda in Notranjske. Za nadmorske višine med 1 600 m in
2 000 m velja vrednost projektne hitrosti 30 m/s, nad 2 000 m pa nad 30 m/s (npr. 40 m/s).
V coni 3 je treba upoštevati hitrost vetra 30 m/s. Zajema območja Primorja in Krasa ter del
Vipavske doline.
4.3.2 Srednja hitrost vetra
(ncpt) SI.1 Faktor usmerjenosti vetra, c
dir
Za vrednost faktorja usmerjenosti vetra c se privzame vrednost 1,0.
dir
(ncpt) SI.2 Upoštevanje kategorije terena
Za nadzemne vode nad 45 kV je treba upoštevati kategorijo II, če v projektni nalogi ni določeno
drugače.
Za nadzemne vode do 45 kV je treba upoštevati kategoriji II in III, če v projektni nalogi ni
določeno drugače.
Faktor dolžine hrapavosti zemljišča z in faktor zemljišča k je treba upoštevati po preglednici 4.1
0 r
iz EN 50341-1:2012.
SIST EN 50341-2-21 : 2023
(ncpt) SI.3 Faktor hribovitosti, co
Za priporočeno vrednost faktorja hribovitosti se privzame vrednost c = 1,0.
o
4.3.3 Srednji tlak vetra
(ncpt) SI.1 Učinek višine in temperature
Pri računanju srednjega tlaka vetra se ne upoštevata vpliva učinka temperature in nadmorske
višine na gostoto zraka. V izračunih je treba upoštevati konservativno vrednost gostote zraka,
ki znaša q = 1,25 kg/m .
h
4.3.4 Jakost turbulence in konični tlak vetra
(ncpt) SI.1 Konični tlak vetra za vode do vključno 45 kV
Za vode z napetostnim nivojem do vključno 45 kV in višino stebrov do 15 m je treba upoštevati
vrednosti koničnega tlaka vetra po conah in kategorijah terena po preglednici 4.1/SI.1.
Za vode z višino stebrov nad 15 m je treba vrednosti upoštevati skladno z določilom iz SI.2.
Preglednica 4.1/SI.1: Konični tlak vetra za vode do vključno 45 kV, v N/m
Kategorija zemljišča
Cona obtežbe vetra
III II
Cona 1 425 583
Cona 2 663 909
Cona 3 952 1 305
(ncpt) SI.2 Izračun koničnega tlaka vetra za nadzemne vode nad 45 kV
Konični tlak vetra q (h) naj se izračuna v skladu z EN 50341-1:2012.
p
4.4 Sile vetra na komponente nadzemnega voda
4.4.1 Sile vetra na vodnike
4.4.1.1 Splošno
(ncpt) SI.1 Referenčna višina nad tlemi
Pri izračunu sile
...
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