SIST EN 50423-3:2005
(Main)Overhead electrical lines exceeding AC 1 kV up to and including AC 45 kV -- Part 3: Set of National Normative Aspects
Overhead electrical lines exceeding AC 1 kV up to and including AC 45 kV -- Part 3: Set of National Normative Aspects
Notes 1, 2 and 3 are normative in Austria:
NOTE 2 The construction of lines with covered conductors (KUF) and reduced internal or external
clearance is permitted in Austria.
NOTE 4 This NNA applies to overhead lines with nominal voltage exceeding AC 1kV up to and including
AC 45 kV and a maximum operating voltage of 52 kV according to ÖVE EN 60071-1. Hereinafter the latter
will be described as high voltage overhead lines, group I.
Freileitungen über AC 1 kV bis einschließlich AC 45 kV -- Teil 3: Nationale Normative Festlegungen
Lignes électriques aériennes dépassant 1 kV AC jusqu'à 45 kV AC -- Partie 3: Aspects Normatifs Nationaux
Nadzemni električni vodi za izmenične napetosti nad 1 kV in do vključno 45 kV – 3. del Zbirka nacionalnih normativnih določil
General Information
Relations
Standards Content (Sample)
SLOVENSKI SIST EN 50423-3:2005
STANDARD
julij 2005
Nadzemni električni vodi za izmenične napetosti nad 1 kV in do vključno 45 kV
– 3. del Zbirka nacionalnih normativnih določil
Overhead electrical lines exceeding AC 1 kV up to and including AC 45 kV – Part 3:
Set of National Normative Aspects
ICS 29.240.20 Referenčna številka
SIST EN 50423-3:2005(en)
© Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno
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EUROPEAN STANDARD EN 50423-3
NORME EUROPÉENNE
EUROPÄISCHE NORM January 2005
ICS 29.240.20
English version
Overhead electrical lines exceeding
AC 1 kV up to and including AC 45 kV
Part 3: Set of National Normative Aspects
Lignes électriques aériennes Freileitungen über AC 1 kV
dépassant 1 kV AC jusqu'à 45 kV AC bis einschließlich AC 45 kV
Partie 3: Aspects Normatifs Nationaux Teil 3: Nationale Normative Festlegungen
This European Standard was approved by CENELEC on 2004-10-01. 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 obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in one official version (English). 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50423-3:2005 E
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EN 50423-3:2005 – 2 –
Foreword
The different parts of this European Standard were prepared by the respective CENELEC National
Committees in cooperation with the Technical Committee CENELEC TC 11, Overhead electrical lines
exceeding 1 kV a.c. (1,5 kV d.c.).
The texts of the drafts were submitted to the Unique Acceptance Procedure and were approved by
CENELEC as EN 50423-3 on 2004-10-01.
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) 2005-10-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2007-10-01
__________
Text of EN 50423-3
Please see the subparts specific to each National Committee.
NOTE This Part 3 of EN 50423 is published by CENELEC in English only.
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National Normative Aspects (NNA)
for
AUSTRIA
based on EN 50423-1:2005
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EN 50423-3-1:2005 - 2/39 - Austria
Contents
1 General scope – Field of application . 4
2 Definitions, symbols and references …………………………………………. 4
2.1 Definitions . 4
2.3 References . 5
4 Actions on lines . 6
4.3.2 Wind loads . 6
4.3.3 Ice loads . 6
4.3.6 Construction and maintenance loads . 7
4.3.10.4 Standard load cases . 7
4.3.11 Partial factors for actions . 12
5 Electrical requirements . 13
5.4 Internal and external clearances . 13
5.4.2.1 General considerations and underlying principles .…. 13
5.4.3 Clearances within the span and at the tower . 17
5.4.4 Clearances to ground in areas remote from buildings, roads,
railways and navigable waterways . 18
5.4.5.2 Clearances to residential and other buildings . 19
5.4.5.3 Clearances to Line near roads, railways, navigable waterways . 21
5.4.5.4 Clearances to other power lines or overhead telecom. lines . 29
5.4.5.5 Clearances to recreational areas . 32
6 Earthing systems . 33
6.3 Construction of earthing systems . 33
6.3.1 Installation of earthing electrodes . 33
8 Foundations ………. 33
8.2 General requirements .…. 33
8.5.2.1 Geotechnical design by calculation, General . 34
8.5.3 Geotechnical design by prescriptive measures . 34
9 Conductors and overhead earthwires (ground wires) with or without
telecommunication circuits . 35
9.1 Introduction .………………………… 35
9.5.6 Test requirements …………………………………. 35
9.6 General requirements . 37
10 Insulators .…. 37
10.1 General .……………………………. 37
10.7 Mechanical requirements . 37
10.10 Characteristics and dimensions of insulators . 37
In addition to the given NNA, the following applies for Austria: . 38
TELECOMMUNICATION LINES CARRIED ON OVERHEAD TRANSMISSION LINES
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Austria - 3/39 - EN 50423-3-1:2005
Foreword
1. The Austrian National Committee (NC) is identified by the following address:
Austrian Electrotechnical Committee
Österreichischer Verband für Elektrotechnik (OVE)
Eschenbachgasse 9, A-1010 Vienna, Austria
Phone no. +43.1.587.63.73
Fax no. +43.1.586.74.08
name/number of relevant subcommittee: Fach(normen)ausschuss L
2. The Austrian NC has prepared this Part 3-1 of EN 50423 listing the Austrian national
normative aspects, under its sole responsibility, and duly passed it through the CENELEC
and CLC/TC 11 procedures.
3. This EN 50423-3-1 is normative in Austria and informative for other countries;
4. This EN 50423-3-1 has to be read in conjunction with EN 50423-1, hereinafter referred to
as Part 1. All clause numbers used in this Part 3-1 correspond to those of Part 1. Specific
subclauses, which are prefixed „AT“, are to be read as amendments to the relevant text in
Part 1. Any necessary clarification regarding the application of Part 3-1 in conjunction
with Part 1 shall be referred to the Austrian NC who will, in cooperation with CLC/TC 11
clarify the requirements.
When no reference is made in Part 3-1 to a specific subclause, then Part 1 applies.
5. In the case of „boxed values“ defined in Part 1, amended values (if any) which are defined
in Part 3-1 shall be taken into account in Austria.
However any boxed value, whether in Part 1 or Part 3-1, shall not be amended in the
direction of greater risk in a Project Specification.
6. The Austrian NC declares in accordance with subclause 3.1 of Part 1 that this Part 3-1
follows the „Empirical Approach“ (subclause 4.3), and that consequently subclause 4.2
„General Approach“ is not applicable for Austria.
7. The national Austrian standards/regulations related to overhead electrical lines exceeding
1 kV (A.C.) are identified/listed in 2.3.
NOTE All national standards referred to in this Part 3-1 will be replaced by the relevant European Standards
as soon as they become available and are declared by the Austrian NC to be applicable and thus reported to
the secretary of CLC/TC 11.
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EN 50423-3-1:2005 - 4/39 - Austria
Clause National regulation
1 General scope – Field of application
(A-dev) AT.1 Notes 1, 2 and 3 are normative in Austria:
NOTE 2 The construction of lines with covered conductors (KUF) and reduced internal or external
clearance is permitted in Austria.
NOTE 4 This NNA applies to overhead lines with nominal voltage exceeding AC 1kV up to and including
AC 45 kV and a maximum operating voltage of 52 kV according to ÖVE EN 60071-1. Hereinafter the latter
will be described as high voltage overhead lines, group I.
2 Definitions, symbols and references
2.1 Definitions
(A-dev) AT.2.(1)
a conductor crosses an object when, as a result of being deflected by wind blowing in
the direction of that facility, the outline of the conductor intersects the outline of the
object
(A-dev) AT.2.(2) crossing span
a span to which the conditions of AT.2.(1) apply
(A-dev) AT.3
In addition to the definition in Part 1:
Conductors
are understood to mean bare, insulated, or sheathed wires and cables suspended
between the supports of an overhead high-tension power transmission line – regardless
of whether they are energized or not. Included here are lines having multiple functions
(composite cables for conductors and earthwires). OPCON and OPGW are to be
considered as conductors.
Covered conductors (KUF) are not shock-proof, i.e. covered conductors being valid with
regard to prodection of contact as bare conductors. For the minimum requirements of
the design of covered conductors see ÖVE/ÖNORM E 8227
(A-dev) AT.11
line groups
are defined as follows in Table 2.1/AT.11
Table 2.1/AT.11 - Line groups
Line Nominal Maximum Operating Proof Alternating Normal Surge
Group Insulation Voltage, Effective Voltage A (Alternating Level (Surge
(series) Value in kV Voltage Holding Holding Voltage)
Voltage) Peak Value
Effective Value in kV in kV
I till 45kV till 52 till 105 till 250
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Austria - 5/39 - EN 50423-3-1:2005
Clause National regulation
(ncpt) AT.30
wooden poles
pylon with a wooden tower body
2.3 References
(A-dev) AT.21 ÖVE-L 1, Construction of overhead power lines up to 1000V
(A-dev) AT.22 ÖNORM B 4007 Scarffoldind – general – use, construction und load
(A-dev) AT.23 ÖNORM B 4700 Reinforced concrete structures – EUROCODE-orientated
analysis, design and detailing
(A-dev) AT.24 ÖVE/ÖNORM E 8227 Covered conductors
(A-dev) AT.25 ÖNORM E 4101 Electrical overhead-lines; Pin insulators type VHD und VHD-G
(A-dev) AT.26 ÖNORM E 4102 Electrical overhead-lines; solid core post insulators VKSt und
VKS
(A-dev) AT.27 ÖVE-EH 41 Earthing in alternating current systems with nominal voltages
exceeding 1 kV
(A-dev) AT.28 ÖVE-L 5, Teil 1 Commissioning report for overhead lines
(A-dev) AT.29 ÖNORM ENV 1994-1-1 Eurocode 4: Design of composite steel and concrete
structures – Part 1-1: General rules and rules for buildings
(A-dev) AT.30 ÖNORM B 4710_1 Concrete – Part 1: Specification, production, use and
verification of conformity
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EN 50423-3-1:2005 - 6/39 - Austria
Clause National regulation
4 Actions on lines
4.3.2 Wind loads
(ncpt) AT.3 :
Table 4.3.2/AT.3 Specific wind pressure acting upon the directly affected
components
2
Values relate to a wind velocity of 120 km/h and a thrust of 700 N/m
Component Specific C . q Reduction
x 120
aerodyn. drag N/m2 factor
coefficient C
x
full flat surfaces 1,6 1112 1
flat lattice walls made of angle profiles 1,4 973 1
made of rods 1,1 765 1
Timber poles, steel poles, concrete poles of 0,7 487 1
circular or near-circular shape
steel poles and concrete poles of hexagonal 1,0 695 1
or octagonal shape
Double poles of in the pole-plane 0,7 487 1
Timber, steel rectangular to pole-plane 0,8 556 1
1)
resp. concrete where e < d
m
wires and d < 15,8 mm 1,15 600 0,75
conductors of
Circular or d > 15,8 mm 1,0 521 0,75
elliptical shape
Aircraft warning and radar sphere d < 1,0 m 0,4 278 1
1)
e . inner distance pole to pole
dm .means diameter of pole
(snc) AT.10: In special cases it may be necessary to assume a greater wind velocity than
indicated in Table 4.3.2/AT.3 (120 km/h).
4.3.3 Ice loads
(A-dev) AT.2: Normal and exceptional additional loads on conductors are to be selected with a
view to the prevailing climatic conditions; the minimum assumptions are:
Normal additional load: (4 + 0,2 x d) in N/m
(d = conductor diameter in mm)
Exceptional additional load 25
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Austria - 7/39 - EN 50423-3-1:2005
Clause National regulation
(snc) AT.3: For towers and equipment the following loading conditions apply:
For Normal additional loads:
(1) Conductor: Normal additional load
(2) Insulator strings of glass or porcelain: minimum 20% of their self weight (for
strings of composite insulators eventually higher percentages are to be
considered.)
(3) Tower body: no additional load
(4) Crossarms made of steel profiles: minimum 40% of their self weight
(5) Crossarms made of other materials: minimum 120 N/m2 acting on total surface
4.3.6 Construction and maintenance loads
(ncpt) AT.1: Construction loads are to be assumed as perpendicularly acting single
loads. They act on
(1) crossarms which jut out more than 1,2 metres: at the crossarm´s end
(2) horizontal bracing of crossarms: in the middle of the bracing (crossarm's upper
not horizontal bracings need not to be assumed with construction loads)
(3) all bracing and diagonals inclined at less than 30 degrees to the horizontal, in the
centre of the diagonals. In areas with climbing facilities (e.g. ladder, steps) on
supports: diagonals of these parts need not to be calculated for construction
loads.
(4) all horizontal bracings of tower bodies in the middle of the bracings (e.g. plan
bracing, secondary bracing)
At (1) and (2) loadings of normal conditions according to 4.3.10.4 are to be assumed
additionally, but not in cases (3) and (4).
For material stress the other regular loading conditions are to be assumed according to
relevant regulations (ÖNORM B 4605)
Poles of wooden towers need not to be assumed with construction loads.
4.3.10.4 Standard load cases
Loading cases as from table 4.3.10.4/AT.2 (suspension and angle suspension towers), table
4.3.10.4/AT.3 (tension and angle tension towers) and table 4.3.10.4/AT.4 (tapping towers) are
to be considered.
(ncpt) AT.1:
Tabelle 4.3.10.4/AT.1 Loading cases for the rating of conductor supports
1 2 3
Poles, except Timber
1 Poles Timber poles
poles
Suspension and angle Table 4.3.10.4/AT.2 Table 4.3.10.4/AT.2
2
suspension towers A, B, C A, B, C, D
Tension and angle Table 4.3.10.4/AT.3 Table 4.3.10.4/AT.3
3
tension towers A, B/C A, B/C, D
Tapping poles Table 4.3.10.4/AT.4 Table 4.3.10.4/AT.4
4
A, B, C A, B, C, D
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EN 50423-3-1:2005 - 8/39 - Austria
Clause National regulation
(ncpt) AT.2 :
Table 4.3.10.4/AT.2 - Load cases for suspension and angle suspension towers
Normal loading conditions
Horizontal
Wind Load: Wind perpendicular to the direction of the line, in the case of angle suspension
forces
towers in the direction of the bisectors, acting upon: tower, equipment, and ice-free
conductors.
Horizontal conductor pull: of all conductors
Vertical Permanent Loads Normal additional loads and construction
forces loads are to be taken into account for the rating
A Upward and downward pulls
of those components for which the additional
Weight of the normal additional load on
consideration of these loads along with the
crossarms, equipment and conductors
other vertical loads produces the less
of the adjacent span halves
favourable stresses
Construction Load
Selfweight of support
Horizontal Wind Load: Wind in direction of the line, in the case of angle suspension towers vertical to
forces
B the bisector of the angles, acting upon: tower, equipment, and ice-free conductors.
Horizontal conductor pull: of all conductors.
Vertical as per loading condition A.
forces
Horizontal Reduction of the horizontal conductor pulls of all conductors in one adjacent span 95%
forces
Horizontal conductor pull of all conductors in the other adjacent span.
C
Vertical as per loading condition A
forces
Horizontal Discontinuation of the horizontal pull of one conductor resp. one bundle conductor in one
forces
adjacent span and reduction of the horizontal conductor pull of this conductor resp.
bundle conductor in the other adjacent span to the following percentages:
for single conductors 40 %
for bundle conductors 20 % of the entire bundle conductor
D
Horizontal conductor pull in all other conductors
Vertical as per loading condition A
forces
For the conductor or bundle conductor with discontinued horizontal conductor pull the upward
or downward pull is discontinued.
For the conductor or bundle conductor with reduced horizontal conductor pull the upward or
downward pull is to be reduced to the same percentage as the horizontal pull.
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Austria - 9/39 - EN 50423-3-1:2005
Clause National regulation
(ncpt) AT.3 :
Table 4.3.10.4/AT.3 - Load cases for tension and angle tension towers
(analogously for terminal tension towers)
Normal loading conditions
Horizontal Wind Load: Wind perpendicular to the direction of the line, in case of angle tension towers in
forces the direction of the bisectors or in that of the main axis of the support which deviates least
from the direction of the resultant horizontal conductor pull, acting upon: tower, equipment,
and ice-free conductors.
Horizontal conductor pull: of all conductors
A Vertical Permanent Loads Normal additional loads and construction
forces loads are to be taken into account for the
Upward and downward pulls
rating of those components for which the
Weight of the normal additional load on
additional consideration of those loads along
crossarms, equipment, and conductors
with the other vertical loads produces the less
of the adjacent span halves
favourable stressing
Construction Load
Selfweight of support
Horizontal Wind Load: Wind in direction of the line, in the case of angle tension towers perpendicular to
forces the bisectors of the angle or vertical to that main axis of the support which deviates least
from the direction of the resultant horizontal conductor pull, acting upon: tower, equipment,
and ice-free conductors.
Reduction of horizontal conductor pulls of all conductors in one adjacent span to 50 %.
B/C
Horizontal conductor pull of all conductors in the other adjacent span.
vertical as per loading condition A.
forces In the case of conductors with reduced horizontal conductor pulls the upward and downward
pulls are to be reduced to 50 %.
Horizontal Discontinuation of the horizontal pull of one tensioned conductor or bundle conductor whilst
forces
D the full horizontal conductor pull is being considered by all other conductors tensioned on
the tower.
Vertical as per loading condition A
forces For the conductor or bundle conductor with discontinued horizontal conductor pull the upward
or downward pull is discontinued.
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EN 50423-3-1:2005 - 10/39 - Austria
Clause National regulation
(ncpt) AT.4:
Table 4.3.10.4/AT.4 - Load cases for tapping towers
Normal loading conditions
Horizon- Wind Load: Wind in the direction of that main axis of the tower which deviates least from
tal forces
the resultant horizontal conductor pulls.
acting upon: the tower, equipment, and conductors free of ice.
Horizontal conductor pull: of all conductors
A Vertical Permanent Loads Normal additional loads and construction
forces loads are to be taken into account for the
Upward and downward pulls
rating of those components for which the
Weight of the normal additional load on
additional consideration of those loads
crossarms, equipment, and conductors
along with the other vertical loads
of the adjacent span halves
produces the less favourable stressing
Construction Load
Selfweight of support
Horizon- Wind Load: Wind perpendicular to that main axis of the tower which deviates least from the
tal forces
resultant horizontal line pulls,
acting upon: the tower, equipment, and conductors free of ice.
Horizontal conductor pulls of all conductors
B
vertical as per loading condition A.
forces
Horizon- Wind Load: Wind perpendicular to that main axis of the tower which deviates least from the
C tal forces
resultant horizontal line pulls, acting upon: the tower, the equipment, and the ice-free
conductors.
Terminated Conductors: Reduction of the horizontal conductor pulls of all conductors in an
adjacent span or more adjacent spans to 50%. In case of wooden tapping poles in A-pole
form only the conductor pulls of non-terminated conductors need to be considered for the
through conductor. Horizontal conductor pulls of all conductors in all other adjacent spans.
Non-terminated Conductors: Reduction of the horizontal conductor pulls of all conductors in
an adjacent span or more adjacent spans to 95%
Horizontal conductor pull of all conductors in the other adjacent spans.
Vertical as per loading condition A
forces In the case of terminated conductors with reduced horizontal conductor pulls the upward and
downward pulls are to be reduced to 50%.
Horizon-
D Horizontal forces Terminated Conductors: Discontinuation of the horizontal conductor
tal forces
pull of a conductor or bundle conductor in a span of the through system whilst in the other
span the full horizontal conductor pull is exerted, and possible simultaneous discontinuation
of the horizontal conductor pull of a conductor or bundle conductor of the tapping system.
Horizontal conductor pull in all other conductors of the adjacent spans.
Horizontal forces Non-terminated Conductors: Discontinuation of the horizontal
conductor pull of a conductor or a bundle conductor in an adjacent span and reduction of the
horizontal conductor pull of this conductor or bundle conductor in the other adjacent span of
each conductor system to the following percentages:
for single conductors 40%,
for bundle conductors 20% of the entire bundle conductor.
Horizontal conductor pull in all other conductors.
Vertical as per loading conditions A
forces In the case of the terminated conductors with discontinued horizontal conductor pull the
upward or downward pull is discontinued. In the case of nonterminated conductors for which
the horizontal conductor pull is discontinued, the upward or downward pull is also
discontinued. In the case of conductors with reduced horizontal conductor pull the upward or
downward pull is reduced to the same percentage as for the horizontal conductor pulls.
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Austria - 11/39 - EN 50423-3-1:2005
Clause National regulation
1)
(ncpt) AT.4: For timber poles of lines Group II with nominal insulation 45 the following applies:
Table 4.3.10.4/AT.4 - Loading assumptions for timber poles
Timber poles lines group II Loading assumption
1)
nominal insulation 45 kV
Suspension and angle suspension towers Table 4.3.10.4/AT.1 A, B, C
Tension and angle tension towers Table 4.3.10.4/AT.2 A, B/C
Tapping poles Table 4.3.10.4/AT.3 A, B, C
1)
Calculation of wooden towers of other Group II -lines (above 45kV) which remain in service for only
a short period is also covered here, provided that they do not violate the Protective Zone of a facility
where Enhanced Safety applies. In the event of violation of the said Protective Zone, complete
loading conditions apply also for timber poles as from 4.3.10.4/AT.1 .AT.3 of lines Group II which
remain in service for only a short period of time.
(ncpt) AT.5: Depending upon the porpuse for which they are used, distinctions are drawn
between:
(1) Suspension and angle suspension towers
(2) Tension and angle tension towers
(3) Tapping poles
(ncpt) AT.6: Table 4.3.10.4/AT.1 shows the loading conditions under which these supports
are to be rated. Table 4.3.10.4/AT.2 to Tabelle 4.3.10.4/AT.4 show the loading
assumptions for these loading conditions
(ncpt) AT.7: If, under special conditions, it is to be assumed that conductor pulls will be
reduced or discontinued completely, it must be assumed that as a result the relevant
least favourable stressing of the component to be rated will apply.
(ncpt) AT.8: If suitable measures are adopted at suspension towers and angle suspension
towers to ensure that there is no stress as per loading conditions D (discontinuation of
the conductor pull of one conductor) or loading conditions C (differential pull), these
loading conditions need not be taken into account. However, if the said measures
ensure only partial relief, the percentages shown in Table 4.3.10.4/AT.1 must be
adjusted to the extent of the effective relief. Reference for loading condition C is on the
basis of the assumption that the conductor on one side of the tower is stressed with the
normal additional load at -5°C whilst on the other side there is no additional load.
Reference for loading condition D is on the basis of the assumption that on one side of
the tower a conductor or a conductor of a bundle conductor has ruptured whereby on
the opposing side the conductor pull reduced by the said special measures must be
taken into account.
In the case of lines equipped with suspension strings it may be additionally assumed for
the purposes of loading conditions C and D that between the tower in question and the
next conductor termination there are three level spans with normal span lengths and
similarly equipped suspension towers.
(ncpt) AT.9: If towers of a multiple-circuit line are initially only partially utilised, this is to be
taken into account in the rating.
(ncpt) AT.10: In unusual cases, under particularly unfavourable climatic conditions, it may be
necessary to assume an additional loading assumption with wind pressure on ice-
covered components
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EN 50423-3-1:2005 - 12/39 - Austria
Clause National regulation
(ncpt) AT.11: If multiple strings are used, for the purpose of rating these supports and the
components of these supports are also to be rated for the case of an individual string
failing in the most unfavourable position.
4.3.11 Partial factors for actions
(ncpt) AT.1:
Table 4.3.11/AT.1 - Partial factors for actions - Ultimate limit states
Values given below supersede those given in tables of Part 1
Type of Partial
Loading condition
tower factors γ
A B C D
Suspension γ 1,3 1,3 1,3 1,3
G
and angle
γ 1,3 1,3 n.a. n.a.
W
suspension
1,3 1,3 1,3 1,3
γ
I
towers
γ n.a. n.a. n.a. n.a.
A
1,3 1,3 1,3 1,3
γ
C
A B/C D
1,3 1,3 1,3
γ
G
Tension
γ 1,3 1,3 1,3
W
and angle
1,3 1,3 1,3
γ
I
tension
γ n.a. n.a. n.a.
A
towers
γ 1,3 1,3 1,3
C
A B C D
1,3 1,3 1,3 1,3
γ
G
Tapping γ 1,3 1,3 n.a. n.a.
W
towers
γ 1,3 1,3 1,3 1,3
I
n.a. n.a. n.a. n.a.
γ
A
γ 1,3 1,3 1,3 1,3
C
Remarks: = Partial Factor for Self Loads
γ
G
γ = Partial Factor for Wind Loads
W
γ = Partial Factor Additional Loads
I
γ = Partial Factor Exceptional loads
A
γ = Partial Factor for Conductor Pull
C
n.a. not applicable
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Austria - 13/39 - EN 50423-3-1:2005
Clause National regulation
5 Electrical requirements
5.4 Internal and external clearances
5.4.2.1 General considerations and underlying principles
(A-dev) AT.1 Overhead HV-lines are to be so constructed that:
(1) conductors which are live are kept at such a distance from one another and from
earthed components of their supports that electrical arc
...
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