IEC 62561-2:2025

IEC 62561-2 ®
Edition 3.0 2025-09
INTERNATIONAL
STANDARD
REDLINE VERSION
Lightning protection system components (LPSC) -
Part 2: Requirements for conductors and earth electrodes
ICS 29.020; 91.120.40 ISBN 978-2-8327-0758-6
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CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Requirements . 10
4.1 General . 10
4.2 Documentation and installation instructions . 10
4.3 Air-termination conductors, air-termination rods, earth lead-in rods catenary
wires and down conductors . 11
4.4 Earth electrodes . 14
4.4.1 General . 14
4.4.2 Earth conductors . 16
4.4.3 Earth rods. 16
4.4.4 Earth plates and equipotential earth grids . 17
4.4.5 Couplers for earth rods . 17
4.5 Earth lead-in conductors and earth plates . 18
4.6 Marking . 18
4.6.1 Content of marking . 18
4.6.2 Durability and legibility. 18
5 Tests . 20
5.1 General test conditions . 20
5.2 Air-termination conductors, air-termination rods, catenary wires, down
conductors, earth lead-in rods conductors, earth conductors, earth plates
and equipotential earth grids . 21
5.2.1 General . 21
5.2.2 Test for thickness of coating . 21
5.2.3 Resistance test for coated conductors . 23
5.2.4 Bend and adhesion Bending test for coated conductors . 24
5.2.5 Environmental test for coated materials conductors . 24
5.2.6 Electrical resistivity test . 24
5.2.7 Tensile strength test . 25
5.2.8 Material, configuration and cross-sectional area test . 26
5.3 Earth rods . 26
5.3.1 General . 26
5.3.2 Test for thickness of coating on earth rods . 26
5.3.3 Adhesion test for copper coated earth rods . 26
5.3.4 Electrical resistance test for coated earth rods . 27
5.3.5 Bend test Bending test for copper coated steel earth rods . 28
5.3.6 Environmental test for coated earth rods . 28
5.3.7 Electrical resistivity test for earth rods . 29
5.3.8 Tensile strength test for earth rods . 29
5.3.9 Test for yield/tensile ratio for copper coated steel earth rods . 29
5.3.10 Material, configuration and cross-sectional area test for earth rods . 30
5.4 Couplers for earth rods . 30
5.4.1 General . 30
5.4.2 Compression test by mechanical means . 30
5.4.3 Environmental test . 33
5.4.4 ElectricalLightning current test . 33
5.4.5 Tensile strength test for couplers of earth rods . 33
5.5 Marking test . 33
5.5.1 General test conditions . 33
5.5.2 Acceptance criteria . 34
5.6 Documentation and installation instructions . 34
5.6.1 General test conditions . 34
5.6.2 Acceptance criteria . 34
6 Electromagnetic compatibility (EMC) . 34
7 Structure and content of the test report. 34
7.1 General . 34
7.2 Report identification . 34
7.3 Specimen description . 35
7.4 Conductor . 35
7.5 Standards and references . 35
7.6 Test procedure. 35
7.7 Testing equipment description . 35
7.8 Measuring instruments description . 35
7.9 Results and parameters recorded . 36
7.10 Statement of pass/ or fail . 36
Annex A (normative) Environmental test for conductors, air-termination
rods and earth lead-in rods . 37
A.1 General . 37
A.2 Salt mist treatment . 37
A.3 Humid sulphurous atmosphere treatment . 37
A.4 Ammonia atmosphere treatment . 37
Annex B (normative) ElectricalLightning current test . 38
B.1 General . 38
B.2 Acceptance criteria . 38
Annex C (normative) Requirements and tests for air-termination conductors, air-
termination rods, catenary wires and down conductors . 39
Annex D (normative) Requirements and tests for earth lead-in conductors, earth
electrodes, equipotential earth grids and couplers for earth rods . 40
Annex E (normative) Flow chartSequence of tests for air-termination conductors, air-
termination rods, catenary wires, earth lead-in rods conductors, down-conductors,
earth conductors, earth plates and equipotential earth grids, see Figure E.1 . 42
Annex F (normative) Flow chartSequence of tests for earth rods . 44
Annex G (normative) Flow chartSequence of tests of couplers for earth rods . 46
Annex H (normative) Material, configuration and cross-sectional area test . 48
H.1 General . 48
H.2 Acceptance criteria for air-termination conductors, air-termination rods,
catenary wires and down conductors . 48
H.3 Acceptance criteria for earth lead-in conductors, earth electrodes,
equipotential earth grids . 48
Annex I (normative) Applicability of previous tests . 49
Bibliography . 50
Figure 1 – Coating measurements around the circumference of a round conductor . 22
Figure 2 – Coating measurements of a plate conductor . 22
Figure 3 – Typical test arrangement for adhesion test . 27
Figure 4 – Definitions of upper yield strength R and tensile strength R . 30
eH m
Figure 5 – Typical test arrangement for the compression test by mechanical means . 32
Figure E.1 – Flow chart of tests for air-termination conductors, air-termination rods,
catenary wires, earth lead-in rods conductors, down-conductors, earth conductors
electrodes and equipotential earth plates grids . 43
Figure F.1 – Flow chart of tests for earth rods . 45
Figure G.1 – Flow chart of tests of couplers for earth rods . 47

Table 1 – Material, configuration and cross-sectional area of air-termination
g
conductors, air-termination rods, earth lead-in rods catenary wires and down-
conductors . 12
Table 2 – Mechanical and electrical characteristics of air-termination
conductors, air-termination rods, earth lead-in rods, down-conductors and earth
electrodes .
Table 2 – Material properties . 13
Table 3 – Material, configuration and cross-sectional area of earth electrodes .
Table 3 – Material, configuration and cross-sectional area of earth lead-in conductors,
earth electrodes and equipotential earth grids . 14
Table B.1 – Lightning impulse current (I ) parameters . 38
imp
Table C.1 – Summary of requirements and tests for various elements tested according
to Table 1 and Table 2 . 39
Table D.1 – Summary of requirements and tests for various elements tested according
to Table 2 and Table 3 . 40
Table I.1 – Differences in the requirements for conductors and earth electrodes
complying with IEC 62561-2:2012 or IEC 62561-2:2018 . 49

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Lightning protection system components (LPSC) -
Part 2: Requirements for conductors and earth electrodes

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
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the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made
to the previous edition IEC 62561-2:2018. A vertical bar appears in the margin wherever a
change has been made. Additions are in green text, deletions are in strikethrough red text.

IEC 62561-2 has been prepared by IEC technical committee 81: Lightning protection. It is an
International Standard.
This third edition cancels and replaces the second edition published in 2018. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) definitions of new conductor types mentioned in this document have been added;
b) the document has been updated in line with IEC 60068-2-52:2017 on salt mist treatment;
c) the document has been updated in line with ISO 22479:2019 on humid sulphurous
atmosphere treatment;
d) a new normative Annex H for material, configuration and cross-sectional area test has been
introduced;
e) a new normative Annex I for applicability of previous tests has been introduced.
f) equipotential earth grid has been introduced.
The text of this International Standard is based on the following documents:
Draft Report on voting
81/794/FDIS 81/800/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 62561 series, published under the general title Lightning protection
system components (LPSC), can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
INTRODUCTION
This part of IEC 62561 deals with the requirements and tests for lightning protection system
components (LPSC), specifically conductors and earth electrodes, used for the installation of a
lightning protection system (LPS) designed and implemented according to the IEC 62305
series.
1 Scope
This part of IEC 62561 specifies the requirements and tests for
– metallic conductors (other than "natural" conductors) that form part of the air-termination
and down-conductor systems, and
– metallic earth electrodes that form part of the earth-termination system.
NOTE 1 Additional requirements can be necessary for conductors and earth electrodes intended for use in
hazardous environments.
NOTE 2 In CENELEC member countries, testing requirements of components for explosive atmospheres are
specified in CLC/TS 50703-2.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068-2-52:19962017, Environmental testing – Part 2-52: Tests – Test Kb: Salt mist, cyclic
(sodium, chloride solution)
IEC 60228, Conductors of insulated cables
IEC 62305-3, Protection against lightning – Part 3: Physical damage to structures and life
hazard
IEC 62305-4, Protection against lightning – Part 4: Electrical and electronic systems within
structures
IEC 62561-1:2012, Lightning protection system components (LPSC) – Part 1, Requirements for
connection components
ISO 2178, Non-magnetic coatings on magnetic substrates – Measurement of coating thickness
– Magnetic method
ISO 1460, Metallic coatings – Hot dip galvanized coatings on ferrous materials – Gravimetric
determination of the mass per unit area
ISO 1461:2022, Hot dip galvanized coatings on fabricated iron and steel articles –
Specifications and test methods
ISO 6892-1, Metallic materials – Tensile testing – Part 1: Method of test at room temperature
ISO 6957:1988, Copper alloys – Ammonia test for stress corrosion resistance
ISO 6988:1985, Metallic and other non-organic coatings – Sulphur dioxide test with general
condensation of moisture
ISO 22479:2019, Corrosion of metals and alloys – Sulphur dioxide test in a humid atmosphere
(fixed gas method)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1
air-termination system
part of an external lightning protection system (LPS using metallic elements such as rods, mesh
conductors or catenary wires) intended to intercept lightning flashes
EXAMPLE Air-termination rods, air-termination conductors and catenary wires.
3.2
air-termination rod
part of the air-termination system consisting of a metal rod for intercepting and conducting
flashes to the down-conductor and earthing system components of the lightning protection
system (LPS)
3.3
air-termination conductor
part of the air-termination system consisting of a conductor for intercepting and conducting
flashes to the down-conductor and earthing system components of the lightning protection
system (LPS)
3.4
catenary wire
part of the air-termination system consisting of an overhead wire for intercepting and conducting
flashes to the down-conductor and earthing system of the lightning protection system (LPS)
3.5
copper coated steel
steel that is manufactured through a continuous electro-plating process of copper over steel
core, resulting in a permanent molecular bond between the two materials
3.6
down-conductor system
part of an external LPS intended to conduct lightning current between the air-termination system
and the earth-termination system
3.7
down-conductor
part of an external lightning protection system, which is intended to conduct lightning current
from the air-termination system to the earth-termination system
part of the down-conductor system intended to conduct lightning current from the air-termination
system to the earth-termination system of the LPS
3.8
earth lead-in conductor
conductor installed between the down-conductor or test joint and the earth electrode intended
to provide connection of the earth electrode with the test joint and can be partially buried in
soil or partially embedded in concrete and partially placed in air
Note 1 to entry: An earth lead-in conductor can also provide mechanical protection against accidental stresses to
the down conductor system.
3.9
earth-termination system
part of an external lightning protection system, which is intended to conduct and disperse
lightning current to the earth
3.10
earth electrode
ground electrode, USA
part or group of parts of the earth-termination system which provides direct electrical contact
with the earth and disperses lightning current into the earth
EXAMPLE Earth rod, earth conductor and earth plate. Tape, wire, earth plate, lattice earth plate, meshed earth
plate, solid earth rod, tubular earth rod.
3.11
earth conductor
ground conductor, USA
earth electrode consisting of a conductor buried in the ground
3.12
earth plate
metallic earth electrode consisting of a metal solid plate buried in the ground or a lattice plate
buried in the ground
3.13
earth rod
earth electrode consisting of a solid or tubular metal rod driven into the ground
3.10
earth rod coupler
part of the earth-termination system that facilitates the coupling of one section of an earth rod
to another for the purpose of deep driving
3.11
driving head
tool used in those applications where it is necessary to drive the earth rod
3.12
earth lead-in rod
rod installed between the down-conductor/test joint and the earth electrode
3.14
earth-rod-driving-head
tool used in those applications where it is necessary to drive the earth rod
3.15
couplers for earth rods
part of the earth-termination system that facilitates the coupling of one section of an earth rod
to another for the purpose of deep driving
Note 1 to entry: Male and female or plug and socket connections of earth rods are also defined as couplers.
3.16
hot dipped galvanized steel
steel coated by a process which alloys with the surface of the base metal when immersing the
metal in a bath of molten zinc at a temperature of around 450 °C (842 °F)
3.17
type test
test required to be made before supplying a type of material covered by IEC 62561-2 on a
general commercial basis, in order to demonstrate satisfactory performance characteristics to
meet the intended application
3.18
stranded conductor
conductor consisting of a number of individual wires or strands all or some of which generally
have a helical form
Note 1 to entry: The cross-section of a stranded conductor can be circular or otherwise shaped.
Note 2 to entry: The term "strand" is also used to designate a single wire.
[SOURCE: IEC 60050-461:2008, 461-01-07]
3.19
rope lay conductor
conductor composed of a central core surrounded by one or more layers of helically laid groups
of wires
3.20
smooth weave stranded conductor
conductor constructed of multi-strand soft drawn wire, interwoven in a basket weave
configuration so as to avoid fraying in application
3.21
equipotential earth grid
mat consisting of an array of conductor intended for potential equalization
4 Requirements
4.1 General
Conductors and earth electrodes shall be designed in such a manner that, when they are
installed in accordance with the manufacturer's instructions, their performance shall be reliable,
stable and safe to persons and surrounding equipment.
The choice of a material depends on its ability to match the particular application requirements
such as life cycle of the material, effects from galvanic corrosion and compatibility with other
interconnected materials or services.
Summaries of the requirements for tests are given in Annex C and Annex D and the sequence
of tests in Annex E, Annex F and Annex G.
4.2 Documentation and installation instructions
The manufacturer or supplier of the conductors and earth electrodes rods shall provide
adequate information in their literature documentation or installation instructions, for example
by drawings or photographs, to ensure that the installer of the conductors and earth electrodes
rods can select and install the materials in a suitable and safe manner, in accordance with
IEC 62305-3 and IEC 62305-4.
Compliance is checked by inspection.
To facilitate the installer, where it is necessary, the manufacturer or supplier may recommend
the proper tools for their installation and instruments in order to perform specified
measurements by IEC 62305 (all parts). In addition, where it is necessary to recommend a
training for the safe selection and use of LPS components.
Documentation and installation instructions content shall not be in contradiction with the content
of the relative testing report of each component.
Instructions are checked as per their completeness in accordance with 5.6.
4.3 Air-termination conductors, air-termination rods, earth lead-in rods catenary
wires and down conductors
The material, configuration and cross-sectional area of the conductors and rods shall be in
accordance with Table 1. Their mechanical and electrical characteristics shall be in accordance
with Table 2.
Other materials may be used if they possess equivalent mechanical and electrical
characteristics and corrosion resistance properties for the intended application.
Other configurations may be used if the relevant dimensions cross-sections are met.
If dimensions, materials or configurations other than those shown in Table 1 and Table 2 are
applied, it is possible to use such after a successful electrical test with lightning current as per
Table B.1, class H, as well as all the tests required by Clause 5.
Coated conductors and air-termination rods shall be corrosion-resistant and the coating shall
exhibit good adherence to the base material.
Compliance is checked by the tests of 5.2.2, 5.2.3, 5.2.4, 5.2.5 and 5.2.6.
Compliance is checked by inspection and by the tests as follows:
a) for coated specimens, according to 5.2.2, 5.2.3, 5.2.4, 5.2.5, 5.2.6, 5.2.7, 5.2.8 and 5.5;
b) for uncoated specimens, according to 5.2.6, 5.2.7, 5.2.8 and 5.5.
NOTE A summary of requirements for the cross-sectional area, mechanical and electrical
characteristics as well as tests is given in Annex C. The corresponding flow chart is shown in
Annex E.
Table 1 – Material, configuration and cross-sectional area of air-termination conductors,
g
air-termination rods, earth lead-in rods catenary wires and down-conductors
a
Material Configuration Recommended dimensions
Cross-sectional area
mm
Copper, Solid tape ≥ 50 2 mm thickness
b
d
≥ 50 8 mm diameter
Tin plated copper
Solid round
f k
≥ 50 1,14 mm up to 1,7 mm strand diameter
Stranded
hg
≥ 176 15 mm diameter
Rod solid round
Tubular rod ≥ 100 2 mm wall thickness
i
Rope lay conductor 1,04 mm strand diameter
≥ 50
and smooth weave
stranded conductor
Aluminium Solid tape ≥ 70 3 mm thickness
Solid round ≥ 50 8 mm diameter
f k
≥ 50 1,63 mm strand diameter
Stranded
j
Rope lay conductor 2,08 mm strand diameter
≥ 50
and smooth weave
stranded conductor
Copper coated
Solid round ≥ 50 8 mm diameter
e
aluminium alloy
Aluminium alloy Solid tape ≥ 50 2,5 mm thickness
Solid round ≥ 50 8 mm diameter
f k
≥ 50 1,7 mm strand diameter
Stranded
hg
≥ 176 15 mm diameter
Rod solid round
Tubular rod ≥ 100 2 mm wall thickness
Hot dipped galvanized Solid tape ≥ 50 2,5 mm thickness
steel
Solid round ≥ 50 8 mm diameter
f
≥ 50 1,7 mm strand diameter
Stranded
hg
≥ 176 15 mm diameter
Rod solid round
Tubular rod ≥ 100 2 mm wall thickness
Solid round ≥ 50 8 mm diameter
a
Material Configuration Recommended dimensions
Cross-sectional area
mm
e
Solid tape ≥ 50 2,5 mm thickness
Copper coated steel
c ih
≥ 50 2 mm thickness
Stainless steel Solid tape
ih
≥ 50 8 mm diameter
Solid round
f
≥ 70 1,7 mm strand diameter
Stranded
hg
≥ 176 15 mm diameter
Rod Solid round
Tubular rod ≥ 100 2 mm wall thickness
NOTE For the application of the conductors, see IEC 62305-3.
a
Manufacturing tolerance: −3 %.
b
Hot dipped or electroplated; minimum thickness coating of 1 μm. There is no requirement to measure the tin
plated plating on copper because it is for aesthetic reasons only.
c
Chromium ≥ 16 %; nickel ≥ 8 %; carbon ≤ 0,08 %.
d 2 2
50 mm (8 mm in diameter) may be reduced to 28 mm (6 mm in diameter) in certain applications where
mechanical strength is not an essential requirement. Consideration should, in this case, be given to reducing
the spacing between the fasteners.
e
Minimum 70 μm radial copper coating of 99,9 % copper content.
f
The cross-sectional area of stranded conductors is determined by the resistance of the conductor according to
IEC 60228 (bare stranded wire should be calculated based upon its diameter by measurements taken with
calipers or a micrometer).
g
If the earth lead-in rod is partially installed in soil it has to fulfil the requirements of Table 2 and Table 3.
hg
Applicable for air-termination rods and earth lead-in rods. For air-termination rods where mechanical stress
such as wind loading is not critical, a 9,5 mm diameter, 1 m long rod may be used.
ih 2
If thermal and mechanical considerations are important, then these values should be increased to 75 mm .
i 2
In some countries (e.g. United States), the minimum cross area is increased to not less than 58 mm for
structures over 23 m in height, with a minimum strand diameter 1,04 mm.
j 2
In some countries (e.g. Unites States), the minimum cross area is increased to not less than 97 mm for
structures over 23 m in height, with a minimum strand diameter 2,08 mm.
k
In Japan, a strand diameter of 2 mm is used.

Table 2 – Material properties
Maximum electrical resistivity Tensile strength
Material
2 b
μΩm
N/mm
Copper
0,019
Aluminium
0,031
Copper coated aluminium alloy
0,031
Copper coated steel
0,258
60 to 510
Aluminium alloy
0,041
Hot dipped galvanized steel
0,258
Aluminium coated steel stranded wire
0,075
Copper coated steel stranded wire
0,064
Hot dipped galvanized steel (earth rods)
0,258
a
350 to 770
Copper coated steel (earth rods)
0,258
Stainless steel
0,824
a
Yield/tensile ratio 0,80 to 0,95.
b
Based on dimensions/tests of only core material of coated conductors.
4.4 Earth electrodes
4.4.1 General
The cross-sectional area of earth electrodes, its material and its configuration shall be in
accordance with Table 3. Moreover, its mechanical and electrical characteristics shall be in
accordance with Table 2.
Other materials may be used if they possess equivalent mechanical and electrical
characteristics and corrosion resistance properties for the intended application.
Other configurations may be used if the relevant dimensions are met.
NOTE A summary of the requirements for dimensions, mechanical and electrical characteristics as well as tests is
given in Annex D.
Table 2 – Mechanical and electrical characteristics of air-termination
conductors, air-termination rods, earth lead-in rods,
down-conductors and earth electrodes
Material Maximum electrical Tensile strength
resistivity
N/mm
µΩm
Copper 0,018 200 to 450
Aluminium 0,03
≤ 150
b
Copper coated aluminium 0,03
≤ 150
Aluminium alloy 0,036 120 to 280
Steel 0,25 290 to 510
Steel (earth rods) 0,25 350 to 770

b
Copper coated steel 0,25
290 to 510
a b
Copper coated steel (earth rods) 0,25 350 to 770
Stainless steel 0,80 350 to 770
a
Yield/tensile ratio 0,80 to 0,95
b
Based on dimensions/tests of only core material of coated conductors.

The cross-sectional area of earth electrodes (earth conductors, earth plates, earth rods) and
earth lead-in conductors partially in soil, their material and their configuration shall be in
accordance with Table 3. Moreover, their mechanical and electrical characteristics shall be in
accordance with Table 2.
Other configurations may be used if the relevant cross-sectional area is met.
If materials or configurations other than those shown in Table 2 and Table 3 are applied, it is
possible to use such after a successful electrical test with lightning current as per Table B.1,
class H, as well as all the tests required by Clause 5.
Coated earth electrodes shall be corrosion-resistant and the coating shall exhibit good
adherence to the base material.
Table 3 – Material, configuration and cross-sectional area of earth lead-in conductors,
earth electrodes and equipotential earth grids
Surface
a
Cross-sectional area
area
Earth
l
Material Recommended dimensions
Configuration
electrode/
Earth Earth
earth lead
p
rod
plate
in
conductor
2 2 2
mm mm cm
i q
Stranded ≥ 50  1,7 mm strand diameter
Solid round ≥ 50  8 mm diameter
Solid tape ≥ 50  2 mm thick
Solid round ≥ 176  15 mm diameter
Copper,
20 mm diameter with 2 mm wall
Tubular rod ≥ 110
thickness
Tin plated
f
g
copper
Solid plate  ≥ 2 500 500 mm × 500 mm and 1,5 mm thick
600 mm × 600 mm consisted of
g
≥ 3 600 25 mm × 2 mm section for tape or
Lattice plate
8 mm diameter for round conductor
Equipotential
Mesh size 250 mm to 500 mm,
o
earth grid conductor 4 mm diameter
Solid round  ≥ 78 10 mm diameter
b
Solid round  14 mm diameter
≥ 150
25 mm diameter with 2 mm wall
b
Tubular rod
≥ 140
thickness
Solid tape ≥ 90 3 mm thick
Hot dipped
Solid plate  ≥ 2 500 500 mm × 500 mm and 3 mm thick
galvanized
steel
600 mm × 600 mm consisted of
d
Lattice plate  ≥ 3 600 30 mm × 3 mm section for tape or
10 mm diameter for round conductor
Equipotential Mesh size 250-500 mm, conductor

o
earth grid 4 mm diameter
e
Profile  3 mm thick
q
Stranded ≥ 70
1,7 mm strand diameter
Bare steel
Solid round ≥ 78 10 mm diameter
k,p
Solid tape ≥ 75 3 mm thick
m h
14 mm diameter
Solid round ≥ 150
Copper
m
≥ 50 8 mm diameter
coated Solid round
c
steel
n
≥ 90  3 mm thick
Solid tape
Solid round ≥ 78 10 mm diameter
h
Solid round ≥ 176  15 mm diameter
Solid tape ≥ 100 2 mm thick
Stainless
25 mm diameter with 2 mm wall
j
Tubular rod ≥ 140
steel
thickness
Equipotential
Mesh size 250 mm to 500 mm,
o
conductor 4 mm diameter
earth grid
Solid plate  ≥ 2 500 500 mm × 500 mm and 2 mm thick
Surface
a
Cross-sectional area
area
Earth
l
Material Recommended dimensions
Configuration
electrode/
Earth Earth
earth lead
p
rod
plate
in
conductor
2 2 2
mm mm cm
NOTE For the application of the earth electrodes, see IEC 62305-3.
a
Manufacturing tolerance: −3 %.
b
Threads, where utilized, shall be machined prior to hot dipped galvanizing.
c
The copper shall be intrinsically bonded to the steel. The coating can be measured using an electronic coating
measuring thickness instrument.
d
Lattice plate constructed with a minimum total conductor length of 4,8 m.
e 2
Different profiles are permitted with a cross section of 290 mm and a minimum thickness of 3 mm, for example
cross profile.
f
Hot dipped or electroplated; minimum thickness coating of 1 μm. There is no need to measure the tin-plated
copper if it is stated that it is present for aesthetic reasons only.
g 2
In some countries (e.g. Unites States), the cross-sectional area may be reduced to ≥ 1 800 cm and the
thickness to ≥ 0,8 mm.
h 2
In some countries (e.g. Unites States), the cross-sectional area may be reduced to 125 mm .
i
The cross-sectional area of insulated stranded conductors is determined by the resistance of the conductor
according to IEC 60228 (bare stranded wire should be calculated based upon its diameter by measurements
taken with calipers or a micrometer).
j
Chromium ≥ 16 %, nickel ≥ 5 %, molybdenum ≥ 2 %, carbon ≤ 0,08 %.
k
Shall be embedded in concrete for a minimum depth of 50 mm.
l
Other configurations may be used if the relevant cross-sectional area are met.
m
250 μm minimum radial coating which may be reduced to not less than 100 μm where special precautions to
avoid mechanical damage of copper during the installation process (e.g. trenches, drilled holes or special
protective tips) are taken according to the manufacturer's instructions.
n
70 μm minimum radial coating; in corrosive environment for solid tape earth conductors, it is recommended to
use copper-coated steel with a coating of 250 μm – for corrosive environment, refer to IEC 62561-7.
o
For equipotential e
...