EN 50341-1:2001/A1:2009
(Amendment)Overhead electrical lines exceeding AC 45 kV - Part 1: General requirements - Common specifications
Overhead electrical lines exceeding AC 45 kV - Part 1: General requirements - Common specifications
Superseded by EN 50341-1:2012
Freileitungen über AC 45 kV - Teil 1: Allgemeine Anforderungen - Gemeinsame Festlegungen
Lignes électriques aériennes dépassant AC 45 kV - Partie 1: Règles générales - Spécifications communes
Nadzemni električni vodi za izmenične napetosti nad 45 kV - 1. del: Splošne zahteve - Skupna določila
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-november-2009
1DG]HPQLHOHNWULþQLYRGL]DL]PHQLþQHQDSHWRVWLQDGN9GHO 6SORãQH
]DKWHYH6NXSQDGRORþLOD
Overhead electrical lines exceeding AC 45 kV -- Part 1: General requirements - Common
specifications
Freileitungen über AC 45 kV -- Teil 1: Allgemeine Anforderungen - Gemeinsame
Festlegungen
Lignes électriques aériennes dépassant AC 45 kV -- Partie 1: Règles générales -
Spécifications communes
Ta slovenski standard je istoveten z: EN 50341-1:2001/A1:2009
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 50341-1/A1
NORME EUROPÉENNE
April 2009
EUROPÄISCHE NORM
ICS 29.240.20
English version
Overhead electrical lines exceeding AC 45 kV -
Part 1: General requirements -
Common specifications
Lignes électriques aériennes Freileitungen über AC 45 kV -
dépassant AC 45 kV - Teil 1: Allgemeine Anforderungen -
Partie 1: Règles générales - Gemeinsame Festlegungen
Spécifications communes
This amendment A1 modifies the European Standard EN 50341-1:2001; it was approved by CENELEC on
2009-04-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this amendment 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 Central Secretariat or to any CENELEC member.
This amendment 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
Central 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, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: avenue Marnix 17, B - 1000 Brussels
© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50341-1:2001/A1:2009 E
Foreword
This amendment was prepared by the Technical Committee CENELEC TC 11, Overhead electrical lines
exceeding 1 kV a.c. (1,5 kV d.c.).
The text of the draft was submitted to the formal vote and was approved by CENELEC as amendment A1 to
EN 50341-1:2001 on 2009-04-01.
The following dates were fixed:
– latest date by which the amendment has to be
implemented at national level by publication of
an identical national standard or by endorsement (dop) 2010-04-01
– latest date by which the national standards conflicting
with the amendment have to be withdrawn (dow) 2012-04-01
__________
- 3 - EN 50341-1:2001/A1:2009
Introduction
Replace by:
Introduction
Detailed structure of the standard
The standard comprises two parts, numbered Part 1 and Part 3.
Part 1: General requirements - Common specifications
This part, also referred to as the Main Body, includes clauses common to all countries. These clauses have
been prepared by Working Groups and approved by CLC/TC 11.
The Main Body is available in English, French and German.
Part 3: National Normative Aspects
The index lists the existing National Normative Aspects (NNAs) related to the different countries.
The National Normative Aspects (NNAs) reflect national practices. They generally include A-deviations,
special national conditions and national complements.
A-deviations:
A-deviations are required by existing national laws or regulations, which cannot be altered at the time of
preparation of the standard.
Reference is made to CENELEC Internal Regulations Part 2, definition 2.17.
Special national conditions (snc):
Special national conditions are national characteristics or practices that cannot be changed even over a long
period, e.g. those due to climatic conditions, earth resistivity, etc.
Reference is made to CENELEC Internal Regulations, Part 2, definition 2.15.
National complements (NCPTs):
National complements reflect national practices, which are neither A-deviations, nor special national
conditions. It has been agreed within CLC/TC 11 that NCPTs should be gradually adapted to the Main Body,
aiming at the usual EN structure including only a Main Body, A-deviations and special national conditions.
Language:
The NNAs are published in English and in the national language(s) of the respective country.
All clauses
In the Main Body text there are many instances where the word “should” has been inadvertently used in place
of “shall”. Until such time as a full revision to this European Standard is completed replace “should” by “shall”
in all cases.
Replace the obsolete references to draft EN(V)s with those indicated in Table 1.
Table 1 – Main Body Specification – Update of references
Clause Old reference to New reference to New title Comment
number EN(V) EN
Foreword prEN 1993-7-1 - - No longer exists.
2.3 ENV 1991-1 1991-1-1 Part 1-1: General actions -
Densities, self weight, imposed
loads - for buildings
2.3 ENV 1991-2-4 1991-1-4 Part 1-4: General actions - wind
actions
2.3 ENV 1992-1-3 No longer exists. Integrated in
ENV 1992-1-1.
2.3 ENV 1992-3 No longer exists. Integrated in
ENV 1992-1-1.
4.2.2.1.5 ENV 1991-2-4, 1991-1-4, Table 4.2.1.
Clause 8 Subclause 4.3.2
4.2.2.4.3 ENV 1991-2-4, 1991-1-4 Formula for G is
x
Clause B.2 replaced by C C .
s d
4.2.2.4.3 ENV 1991-2-4, 1991-1-1
Clause 10
4.2.2.4.4 ENV 1991-2-4, 1991-1-1
Clause 10
7.2.1 ENV 1993-1-1, Annex B does not
Clause 3, deal with material
Annexes B and D and Annex D does
not exist.
7.2.2 ENV 1993-1-3 1993-1-3
7.2.4 ENV 1993-1-1, This annex no longer exists.
Annex C
- 5 - EN 50341-1:2001/A1:2009
1 Scope
Replace NOTE 2 by the following:
NOTE 2 Design and construction of overhead lines with insulated conductors, where internal and external clearances can be smaller
than specified in the standard, are not included. Other requirements of the standard may be applicable, and where necessary NNAs
shall be consulted.
Add the following NOTE 4:
NOTE 4 The specific definition as to the meaning and extent of a “new overhead line” is to be identified by each NC within their own
NNA. At the least, it shall mean a totally new line between two points, A and B.
2 Definitions, symbols and references
Add the following definitions:
2.1.107
composite insulator
insulator made of at least two insulating parts, namely a core and a housing, equipped with end fittings
NOTE Composite insulators, for example, can consist either of individual sheds mounted on the core, with or without an intermediate
sheath, or alternatively, of a housing directly moulded or cast in one or several pieces onto the core.
2.1.108
anti-cascading tower
tension or suspension tower specially designed with higher strength to avoid cascade failures and installed at
a nominated frequency of towers to limit damage and permit quick restoration of failed towers and
conductor(s)
3 Basis of design
3.2.2 Reliability of overhead lines
Add the following paragraphs at the end of the existing clause as an informative note:
NOTE It is important to note that increasing the Reliability Level is not the only way to improve continuity of service of an overhead
line. The reference reliability level is generally regarded as providing an acceptable reliability level in respect of continuity of service and
safety, but in fact a designer shall consider the following two aspects:
Safety of the public: the reference return period of 50 years gives a high level of reliability. The probability of failure is acceptable in
respect of public safety, because the combined probability resulting in human injury is very low. Moreover, as components are designed
as complete systems rather than individually in isolation, and because they are usually designed prior to specific knowledge of the real
line parameters (e.g. span length), the use factor has a positive influence on actual line reliability.
Continuity of service: it is possible to increase the availability by increasing the return period (upgrading) but it is not the only solution.
It is also possible to increase the service life by creating redundancy, constructing other overhead lines, or having more lines radiating
from substations thereby improving design by strength coordination, limiting damage, installing anti-cascading towers, and by setting an
emergency restoration plan to repair damage very quickly.
Overall costs are not only determined by the probability of failure, but mostly by the possible consequence of failure, including the
uncontrollable propagation of failure, and this may extend well beyond the initial failure. Such consequences can be reduced
significantly by the following cost-effective measures such as: strength coordination, design of supports to resist torsional and
longitudinal security loadings, load control devices, de-icing methods, anti-cascading towers, and construction of other overhead lines,
etc. (i.e. proactive solutions); emergency restoration structures, training of linemen, etc. (i.e. reactive solutions).
3.5 Material properties
Delete the note at the end of this subclause.
4 Actions on lines
4.2.4.4 Equivalent diameter D of ice covered conductor
Replace the symbol definition in the formula:
I is the factored ice load (N/m) according to the wind combination as specified in 4.2.4.1. It includes all
relevant combination and partial load factors for the reliability level concerned.
In the equations of 3.7.4, it is calculated as follows:
I = γ Q = γ I formula 3.7.4 (1) for dominating ice load
Q1 1K I K
I = Ψ Q = Ψ I formula 3.7.4 (1) for dominating wind load
Q2 2K I K
where
I is the reference (characteristic) ice load.
K
4.2.5 Temperature effects
Replace this subclause by the following:
4.2.5 Temperature effects
Temperature effects in five different design situations may generally apply as described below. They will
depend on other climatic actions that may be present:
a) a minimum temperature to be considered with no other climatic action, if this is relevant;
b) a normal ambient reference temperature assumed for the extreme wind speed condition;
c) a reduced wind speed combined with a minimum temperature condition to be considered, if relevant;
d) a temperature to be assumed with icing. For both of the main types of icing (precipitation icing and
o
incloud icing) a temperature of 0 C may be used, unless otherwise specified. A lower temperature shall
be taken into account in regions where the temperature often drops significantly after a snowfall;
e) a temperature to be used for the combination of wind and ice.
It is expected that lower minimum temperatures will be applicable for the longer return periods T indicated in
Table 3.1.
The relevant temperatures and associated design situations are given in the NNAs.
4.2.10.2 Standard load cases
Replace this subclause by the following:
4.2.10.2 Standard load cases
For control of adequate reliability and functions under service conditions of the overhead line, standard load
cases (indicated in Table 4.2.7) and options given below may be defined in the NNAs.
- 7 - EN 50341-1:2001/A1:2009
Table 4.2.7 – Standard load cases (normative)
Load Load as per
Remark
Conditions
case subclause
1a Extreme wind load See (a)
4.2.2
1b Wind load at a minimum temperature If relevant, see 4.2.5
2a Uniform ice loads on all spans
2b Uniform ice loads, transversal bending If relevant, see (b)
4.2.3
2c Unbalanced ice loads, longitudinal bending See (c)
2d Unbalanced ice loads, torsional bending If relevant, see (d)
3 4.2.4 Combined wind and ice loads See (e)
4 4.2.6 Construction and maintenance loads
5a 4.2.7 (a) Security loads, torsional loads Reduced partial factors for
5b 4.2.7 (b) Security loads, longitudinal loads material properties may apply as
given in Clauses 7 and 8.
In all load cases, the vertical component of the permanent actions as given in 4.2.1 shall be included. Where
permanent actions reduce the effects of other actions such as uplift on a foundation, the minimum value of
the permanent action shall be applied, for example minimum allowed ratio of weight-to-wind span.
If applicable and stated in the Project Specification, load cases involving short circuit loads or other special
loads in accordance with 4.2.8 and 4.2.9, respectively, shall be investigated.
Items (a) to (e) apply as given in Table 4.2.7:
(a) A wind direction normal to the line shall be considered and at all other angles which may be critical for
the design.
Wind load on all spans in one direction from the support resulting in longitudinal loads may be
considered in the design of the relevant supports, where this condition is not adequately addressed by
other defined load cases (optional).
(b) In load case 2b, a reduced ice load equal to the characteristic ice load multiplied by a reduction factor
α on all the conductors on all the cross-arms on one side only of the support shall be investigated. This
load case is illustrated in Figure 4.2.4. Where this load condition can be ignored α is defined as 1
(optional).
(c) In load case 2c, the characteristic ice load on all the conductors in one direction only from all the
cross-arms of the support shall be multiplied by a reduction factor α and in the other direction by
...
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