IEC 60502-1:2004+AMD1:2009 CSV

IEC 60502-1 ®
Edition 2.1 2009-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Power cables with extruded insulation and their accessories for rated voltages
from 1 kV (U = 1,2 kV) up to 30 kV (U = 36 kV) –
m m
Part 1: Cables for rated voltages of 1 kV (U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
Câbles d'énergie à isolant extrudé et leurs accessoires pour des tensions
assignées de 1 kV (U = 1,2 kV) à 30 kV (U = 36 kV) –
m m
Partie 1: Câbles de tensions assignées de 1 kV (U = 1,2 kV) et 3 kV
m
(U = 3,6 kV)
m
IEC 60502-1:2009-11(en-fr)
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IEC 60502-1 ®
Edition 2.1 2009-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Power cables with extruded insulation and their accessories for rated voltages

from 1 kV (U = 1,2 kV) up to 30 kV (U = 36 kV) –
m m
Part 1: Cables for rated voltages of 1 kV (U = 1,2 kV) and 3 kV (U = 3,6 kV)

m m
Câbles d'énergie à isolant extrudé et leurs accessoires pour des tensions

assignées de 1 kV (U = 1,2 kV) à 30 kV (U = 36 kV) –

m m
Partie 1: Câbles de tensions assignées de 1 kV (U = 1,2 kV) et 3 kV
m
(U = 3,6 kV)
m
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.060.20 ISBN 978-2-8891-0200-6

– 2 – 60502-1  IEC:2004+A1:2009
CONTENTS
FOREWORD . 6

1 Scope . 8
2 Normative references. 8
3 Terms and definitions . 9
3.1 Definitions of dimensional values (thicknesses, cross-sections, etc.) . 9
3.2 Definitions concerning the tests . 10
4 Voltage designations and materials . 10
4.1 Rated voltages . 10
4.2 Insulating compounds . 11
4.3 Sheathing compounds . 12
5 Conductors . 13
6 Insulation . 13
6.1 Material . 13
6.2 Insulation thickness . 13
7 Assembly of multicore cables, inner coverings and fillers . 15
7.1 Inner coverings and fillers . 15
7.2 Cables with rated voltage 0,6/1 (1,2) kV . 15
7.3 Cables with rated voltage 1,8/3 (3,6) kV . 16
8 Metallic layers for single-core and multicore cables . 16
9 Metallic screen . 17
9.1 Construction . 17
9.2 Requirements . 17
10 Concentric conductor . 17
10.1 Construction . 17
10.2 Requirements . 17
10.3 Application. 17
11 Metallic sheath . 17
11.1 Lead sheath. 17
11.2 Other metallic sheaths . 18
12 Metallic armour . 18
12.1 Types of metallic armour. 18
12.2 Materials . 18
12.3 Application of armour . 19
12.4 Dimensions of the armour wires and armour tapes . 20
12.5 Correlation between cable diameters and armour dimensions . 20
12.6 Round or flat wire armour . 21
12.7 Double tape armour . 21
13 Oversheath . 21
13.1 General . 21
13.2 Material . 21
13.3 Thickness . 22

60502-1  IEC:2004+A1:2009 – 3 –
14 Test conditions . 22
14.1 Ambient temperature . 22
14.2 Frequency and waveform of power frequency test voltages . 22
14.3 Waveform of impulse test voltages . 22
15 Routine tests . 22
15.1 General . 22
15.2 Electrical resistance of conductors . 23
15.3 Voltage test . 23
16 Sample tests . 24
16.1 General . 24
16.2 Frequency of sample tests . 24
16.3 Repetition of tests . 25
16.4 Conductor examination . 25
16.5 Measurement of thickness of insulation and of non-metallic sheaths (including
extruded separation sheaths, but excluding inner extruded coverings) . 25
16.6 Measurement of thickness of lead sheath . 26
16.7 Measurement of armour wires and tapes . 26
16.8 Measurement of external diameter . 27
16.9 Hot set test for EPR, HEPR and XLPE insulations and elastomeric sheaths . 27
17 Type tests, electrical . 27
17.1 Insulation resistance measurement at ambient temperature . 27
17.2 Insulation resistance measurement at maximum conductor temperature . 28
17.3 Voltage test for 4 h . 29
17.4 Impulse test for cables of rated voltage 1,8/3 (3,6) kV . 29
18 Type tests, non-electrical . 29
18.1 Measurement of thickness of insulation . 29
18.2 Measurement of thickness of non-metallic sheaths (including extruded
separation sheaths, but excluding inner coverings) . 30
18.3 Tests for determining the mechanical properties of insulation before and
after ageing . 30
18.4 Tests for determining the mechanical properties of non-metallic sheaths
before and after ageing . 30
18.5 Additional ageing test on pieces of completed cables . 31
18.6 Loss of mass test on PVC sheaths of type ST . 31
18.7 Pressure test at high temperature on insulations and non-metallic sheaths . 32
18.8 Test on PVC insulation and sheaths and halogen free sheaths at low
temperatures . 32
18.9 Test for resistance of PVC insulation and sheaths to cracking (heat shock test) . 32
18.10 Ozone resistance test for EPR and HEPR insulations . 32
18.11 Hot set test for EPR, HEPR and XLPE insulations and elastomeric sheaths . 32
18.12 Oil immersion test for elastomeric sheaths . 32
18.13 Water absorption test on insulation . 33
18.14 Fire tests . 33
18.15 Measurement of carbon black content of black PE oversheaths . 34
18.16 Shrinkage test for XLPE insulation . 34
18.17 Special bending test . 34
18.18 Determination of hardness of HEPR insulation . 35
18.19 Determination of the elastic modulus of HEPR insulation . 35

– 4 – 60502-1  IEC:2004+A1:2009
18.20 Shrinkage test for PE oversheaths . 35
18.21 Additional mechanical tests on halogen free oversheaths . 35
18.22 Water absorption test for halogen free oversheaths . 35
19 Electrical tests after installation . 36

Annex A (normative) Fictitious calculation method for determination of dimensions of
protective coverings . 45
A.1 General. 45
A.2 Method . 45

Annex B (normative) Rounding of numbers . 51
B.1 Rounding of numbers for the purpose of the fictitious calculation method . 51
B.2 Rounding of numbers for other purposes . 51

Annex C (normative) Determination of hardness of HEPR insulations . 53
C.1 Test piece . 53
C.2 Test procedure . 53

Figure C.1 – Test on surfaces of large radius of curvature . 54
Figure C.2 – Test on surfaces of small radius of curvature . 55

Table 1 – Recommended rated voltages U . 11
Table 2 – Insulating compounds . 11
Table 3 – Maximum conductor temperatures for different types of insulating compound . 12
Table 4 – Maximum conductor temperatures for different types of sheathing compound . 12
Table 5 – Nominal thickness of PVC/A insulation . 13
Table 6 – Nominal thickness of cross-linked polyethylene (XLPE) insulation . 14
Table 7 – Nominal thickness of ethylene propylene rubber (EPR) and hard ethylene
propylene rubber (HEPR) insulation . 14
Table 8 – Thickness of extruded inner covering . 15
Table 9 – Nominal diameter of round armour wires . 20
Table 10 – Nominal thickness of armour tapes . 20
Table 11 – Routine test voltages . 24
Table 12 – Number of samples for sample tests . 25
Table 13 – Electrical type test requirements for insulating compounds . 36
Table 14 – Non-electrical type tests (see Tables 15 to 23) . 37
Table 15 – Test requirements for mechanical characteristics of insulating compounds
(before and after ageing) . 38
Table 16 – Test requirements for particular characteristics for PVC insulating compound . 39
Table 17 – Test requirements for particular characteristics of various cross-linked
insulating compounds . 40
Table 18 – Test requirements for mechanical characteristics of sheathing compounds
(before and after ageing) . 41
Table 19 – Test requirements for particular characteristics for PVC sheathing
compounds . 42
Table 20 – Test requirements for particular characteristics of thermoplastic PE
sheathing compounds . 43

60502-1  IEC:2004+A1:2009 – 5 –
Table 21 – Test requirements for particular characteristics of halogen free sheathing
compound . 43
Table 22 – Test requirements for particular characteristics of elastomeric sheathing
compound . 44
Table 23 – Test methods and requirements for halogen free compounds . 44
Table A.1 – Fictitious diameter of conductor . 48
Table A.2 – Assembly coefficient k for laid-up cores . 47
Table A.3 – Increase of diameter for concentric conductors and metallic screens . 48
Table A.4 – Increase of diameter for additional bedding . 50

– 6 – 60502-1  IEC:2004+A1:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
POWER CABLES WITH EXTRUDED INSULATION
AND THEIR ACCESSORIES FOR RATED VOLTAGES
FROM 1 kV (U = 1,2 kV) UP TO 30 kV (U = 36 kV) –
m m
Part 1: Cables for rated voltages of 1 kV
(U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60502-1 has been prepared by IEC technical committee 20: Electric
cables.
This consolidated version of IEC 60502-1 consists of the second edition (2004) [documents
20/683/FDIS and 20/691/RVD] and its amendment 1 (2009) [documents 20/1063/FDIS and
20/1069/RVD].
The technical content is therefore identical to the base edition and its amendment and has
been prepared for user convenience.
It bears the edition number 2.1.
A vertical line in the margin shows where the base publication has been modified by
amendment 1.
60502-1  IEC:2004+A1:2009 – 7 –
The main changes with respect to the first edition relate to insulation and oversheath thickness
requirements, and inclusion of constructions and requirements for halogen free cables with
reduced flame propagation and low levels of smoke emission.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 60502 consists of the following parts, under the general title Power cables with extruded
insulation and their accessories for rated voltages from 1 kV (U = 1,2 kV) up to 30 kV
m
(U = 36 kV):
m
Part 1: Cables for rated voltages of 1 kV (U = 1,2 kV) and 3 kV (U = 3,6 kV);
m m
= 7,2 kV) up to 30 kV (U = 36 kV);
Part 2: Cables for rated voltages from 6 kV (U
m m
Part 3: Reserved;
Part 4: Test requirements on accessories for cables with rated voltages from 6 kV
(U = 7,2 kV) up to 30 kV (U = 36 kV).
m m
The committee has decided that the contents of the base publication and its amendments will
remain unchanged until the maintenance result date indicated on the IEC web site under
"http://webstore.iec.ch" in the data related to the specific publication. At this date,
the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 8 – 60502-1  IEC:2004+A1:2009
POWER CABLES WITH EXTRUDED INSULATION
AND THEIR ACCESSORIES FOR RATED VOLTAGES
FROM 1 kV (U = 1,2 kV) UP TO 30 kV (U = 36 kV) –
m m
Part 1: Cables for rated voltages of 1 kV
(U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
1 Scope
This part of IEC 60502 specifies the construction, dimensions and test requirements of power
cables with extruded solid insulation for rated voltages of 1 kV (U = 1,2 kV) and 3 kV (U =
m m
3,6 kV) for fixed installations such as distribution networks or industrial installations.
This standard includes cables which exhibit properties of reduced flame spread, low levels of
smoke emission and halogen-free gas emission when exposed to fire.
Cables for special installation and service conditions are not included, for example cables for
overhead networks, the mining industry, nuclear power plants (in and around the containment
area), submarine use or shipboard application.
2 Normative references
The following referenced documents are indispensable for the application 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 60038:1983, IEC standard voltages
IEC 60060-1:1989, High-voltage test techniques – Part 1: General definitions and test
requirements
IEC 60183:1984, Guide to the selection of high-voltage cables
IEC 60228:1978, Conductors of insulated cables
IEC 60230:1966, Impulse tests on cables and their accessories
IEC 60332-1:1993, Tests on electric cables under fire conditions – Part 1: Test on a single
vertical insulated wire or cable
IEC 60332-3-24:2000, Tests on electric cables under fire conditions – Part 3-24: Test for
vertical flame spread of vertically-mounted bunched wires or cables – Category C
IEC 60502-2:1997, Power cables with extruded insulation and their accessories for rated
voltages from 1 kV (U = 1,2 kV) up to 30 kV (U = 36 kV) – Part 2: Cables for rated voltages
m m
from 6 kV (U = 7,2 kV) up to 30 kV (U = 36 kV)
m m
IEC 60684-2:1987, Flexible insulating sleeving – Part 2: Methods of test
IEC 60724:2000, Short-circuit temperature limits of electric cables with rated voltages of 1 kV
(U = 1,2 kV) and 3 kV (U = 3,6 kV)
m m
IEC 60754-1:1994, Test on gases evolved during combustion of materials from cables – Part 1:
Determination of the amount of halogen gas

60502-1  IEC:2004+A1:2009 – 9 –
IEC 60754-2:1991, Test on gases evolved during combustion of electric cables – Part 2:
Determination of degree of acidity of gases evolved during the combustion of materials taken
from electric cables by measuring pH and conductivity
IEC 60811-1-1:1993, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section 1: Measurement of thickness and
overall dimensions – Tests for determining the mechanical properties
IEC 60811-1-2:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section 2: Thermal ageing methods
IEC 60811-1-3:1993, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section 3: Methods for determining the
density – Water absorption tests – Shrinkage test
IEC 60811-1-4:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 1: Methods for general application – Section 4: Tests at low temperature
IEC 60811-2-1:1998, Insulating and sheathing materials of electric and optical cables –
Common test methods – Part 2-1: Methods specific to elastomeric compounds – Ozone
resistance, hot set and mineral oil immersion tests
IEC 60811-3-1:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 3: Methods specific to PVC compounds – Section 1: Pressure test at high
temperature – Tests for resistance to cracking
IEC 60811-3-2:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 3: Methods specific to PVC compounds – Section 2: Loss of mass test – Thermal
stability test
IEC 60811-4-1:1985, Common test methods for insulating and sheathing materials of electric
cables – Part 4: Methods specific to polyethylene and polypropylene compounds – Section 1:
Resistance to environmental stress cracking – Wrapping test after thermal ageing in air –
Measurement of the melt flow index – Carbon black and/or mineral content measurement in PE
IEC 61034-2: 1997, Measurement of smoke density of cables burning under defined conditions –
Part 2: Test procedure and requirements
ISO 48:1994, Rubber, vulcanized or thermoplastic – Determination of hardness (hardness
between 10 IRHD and 100 IRHD)
3 Terms and definitions
For the purposes of this document, the following definitions apply.
3.1 Definitions of dimensional values (thicknesses, cross-sections, etc.)
3.1.1
nominal value
value by which a quantity is designated and which is often used in tables
NOTE Usually, in this standard, nominal values give rise to values to be checked by measurements taking into
account specified tolerances.
3.1.2
approximate value
value which is neither guaranteed nor checked; it is used, for example, for the calculation of
other dimensional values
– 10 – 60502-1  IEC:2004+A1:2009
3.1.3
median value
when several test results have been obtained and ordered in an increasing (or decreasing)
succession, the median value is the middle value if the number of available values is odd, and
the mean of the two middle values if the number is even
3.1.4
fictitious value
value calculated according to the "fictitious method'' described in Annex A
3.2 Definitions concerning the tests
3.2.1
routine tests
tests made by the manufacturer on each manufactured length of cable to check that each
length meets the specified requirements
3.2.2
sample tests
tests made by the manufacturer on samples of completed cable or components taken from a
completed cable, at a specified frequency, so as to verify that the finished product meets the
specified requirements
3.2.3
type tests
tests made before supplying, on a general commercial basis, a type of cable covered by this
standard, in order to demonstrate satisfactory performance characteristics to meet the
intended application
NOTE These tests are of such a nature that, after they have been made, they need not be repeated, unless
changes are made in the cable materials or design or manufacturing process which might change the performance
characteristics.
3.2.4
electrical tests after installation
tests made to demonstrate the integrity of the cable and its accessories as installed
4 Voltage designations and materials
4.1 Rated voltages
The rated voltages U /U (U ) of the cables considered in this standard are 0,6/1 (1,2) kV and
0 m
1,8/3 (3,6) kV.
NOTE 1 The voltages given above are the correct designations although in some countries other designations are
used, e.g. 1,7/3 kV or 1,9/3,3 kV instead of 1,8/3 kV.
In the voltage designation of cables U /U (U ):
0 m
U is the rated power frequency voltage between conductor and earth or metallic screen for
which the cable is designed;
U is the rated power frequency voltage between conductors for which the cable is designed;
U is the maximum value of the "highest system voltage'' for which the equipment may be
m
used (see IEC 60038).
The rated voltage of the cable for a given application shall be suitable for the operating
conditions in the system in which the cable is used. To facilitate the selection of the cable,
systems are divided into three categories:

60502-1  IEC:2004+A1:2009 – 11 –
– Category A: this category comprises those systems in which any phase conductor that
comes in contact with earth or an earth conductor is disconnected from the
system within 1 min;
– Category B: this category comprises those systems which, under fault conditions, are
operated for a short time with one phase earthed. This period, according to
IEC 60183, should not exceed 1 h. For cables covered by this standard, a
longer period, not exceeding 8 h on any occasion, can be tolerated. The total
duration of earth faults in any year should not exceed 125 h;
– Category C: this category comprises all systems which do not fall into category A or B.
NOTE 2 It should be realized that in a system where an earth fault is not automatically and promptly isolated, the
extra stresses on the insulation of cables during the earth fault reduce the life of the cables to a certain degree. If
the system is expected to be operated fairly often with a permanent earth fault, it may be advisable to classify the
system in Category C.
The values of U recommended for cables to be used in three-phase systems are listed in
Table 1.
Table 1 – Recommended rated voltages U
Highest system voltage Rated voltage (U )
(U ) kV
m
kV Categories A and B Category C
1,2 0,6 0,6
*
3,6 1,8 3,6
*
This category is covered by 3,6/6 (7,2) kV cables according to IEC 60502-2.

4.2 Insulating compounds
The types of insulating compound covered by this standard are listed in Table 2, together with
their abbreviated designations.
Table 2 – Insulating compounds
Abbreviated
Insulating compound
designation
a) Thermoplastic
*
Polyvinyl chloride intended for cables with rated voltages U /U ≤ 1,8/3 kV PVC/A
b) Cross-linked:
Ethylene propylene rubber or similar (EPM or EPDM) EPR
High modulus or hard grade ethylene propylene rubber HEPR
Cross-linked polyethylene XLPE
* Insulating compound based on polyvinyl chloride intended for cables with rated voltages U /U = 3,6/6 kV is
designated PVC/B in IEC 60502-2.

The maximum conductor temperatures for different types of insulating compound covered by
this standard are given in Table 3.

– 12 – 60502-1  IEC:2004+A1:2009
Table 3 – Maximum conductor temperatures for different types of insulating compound
Maximum conductor temperature
°C
Insulating compound
Short-circuit
Normal operation (5 s maximum
duration)
Polyvinyl chloride (PVC/A)
Conductor cross-section ≤300 mm 70 160
70 140
Conductor cross-section >300 mm
Cross-linked polyethylene (XLPE) 90 250
Ethylene propylene rubber (EPR and HEPR) 90 250

The temperatures in Table 3 are based on the intrinsic properties of the insulating materials. It
is important to take into account other factors when using these values for the calculation of
current ratings.
For example, in normal operation, if a cable directly buried in the ground is operated under
continuous load (100 % load factor) at the maximum conductor temperature shown in the table,
the thermal resistivity of the soil surrounding the cable may, in the course of time, increase
from its original value as a result of drying-out processes. As a consequence, the conductor
temperature may greatly exceed the maximum value. If such operating conditions are foreseen,
adequate provisions shall be made.
For guidance on the short-circuit temperatures, reference should be made to IEC 60724.
4.3 Sheathing compounds
The maximum conductor temperatures for the different types of sheathing compound covered
by this standard are given in Table 4.
Table 4 – Maximum conductor temperatures for different types of sheathing compound
Maximum conductor
Abbreviated temperature
Sheathing compound
designation in normal operation
°C
a) Thermoplastic:
Polyvinyl chloride (PVC) ST 80
ST 90
ST 80
Polyethylene
ST 90
Halogen free ST 90
b) Elastomeric:
Polychloroprene, chlorosulfonated polyethylene SE 85
or similar polymers
60502-1  IEC:2004+A1:2009 – 13 –
5 Conductors
The conductors shall be either of Class 1 or Class 2 of plain or metal-coated annealed copper
or of plain aluminium or aluminium alloy, or of Class 5 of plain or metal-coated copper in
accordance with IEC 60228.
6 Insulation
6.1 Material
The insulation shall be extruded dielectric of one of the types listed in Table 2.
For halogen free cables, the insulation shall meet the requirements given in Table 23.
6.2 Insulation thickness
The nominal insulation thicknesses are specified in Tables 5 to 7.
The thickness of any separator shall not be included in the thickness of the insulation.
Table 5 – Nominal thickness of PVC/A insulation
Nominal cross-sectional Nominal thickness of insulation at rated voltage
area of conductor U /U (U )
0 m
0,6/1 (1,2) kV 1,8/3 (3,6) kV
mm mm mm
1,5 and 2,5 0,8 –
4 and 6 1,0 –
10 and 16 1,0 2,2
25 and 35 1,2 2,2
50 and 70 1,4 2,2
95 and 120 1,6 2,2
150 1,8 2,2
185 2,0 2,2
240 2,2 2,2
300 2,4 2,4
2,6 2,6
500 to 800 2,8 2,8
1 000 3,0 3,0
NOTE Any conductor cross-section smaller than those given in this table is not recommended.

– 14 – 60502-1  IEC:2004+A1:2009
Table 6 – Nominal thickness of cross-linked polyethylene (XLPE) insulation
Nominal cross-sectional Nominal thickness of insulation at rated voltage
area of conductor U /U (U )
0 m
0,6/1 (1,2) kV 1,8/3 (3,6) kV
mm mm mm
1,5 and 2,5 0,7 –
4 and 6 0,7 –
10 and 16 0,7 2,0
25 and 35 0,9 2,0
50 1,0 2,0
70 and 95 1,1 2,0
120 1,2 2,0
150 1,4 2,0
185 1,6 2,0
240 1,7 2,0
1,8 2,0
400 2,0 2,0
500 2,2 2,2
630 2,4
2,4
800 2,6 2,6
1 000 2,8 2,8
NOTE Any conductor cross-section smaller than those given in this table is not recommended.

Table 7 – Nominal thickness of ethylene propylene rubber (EPR)
and hard ethylene propylene rubber (HEPR) insulation
Nominal cross-sectional Nominal thickness of insulation at rated voltage
area of conductor U /U (U )
0 m
0,6/1 (1,2) kV 1,8/3 (3,6) kV
EPR HEPR EPR HEPR
mm
mm mm mm mm
1,5 and 2,5 1,0 0,7 – –
4 and 6 1,0 0,7
– –
10 and 16 1,0 0,7 2,2 2,0
25 and 35 1,2 0,9 2,2 2,0
50 1,4 1,0 2,2
2,0
70 1,4 1,1 2,2 2,0
95 1,6 1,1 2,4 2,0
120 1,6 1,2 2,4 2,0
150 1,8 1,4 2,4 2,0
185 2,0 1,6 2,4 2,0
240 2,2 1,7 2,4 2,0
300 2,4 1,8 2,4 2,0
400 2,6 2,0 2,6 2,0
500 2,8 2,2 2,8 2,2
630 2,8 2,4 2,8 2,4
800 2,8 2,6 2,8 2,6
1 000 3,0 2,8 3,0 2,8
NOTE Any conductor cross-section smaller than those given in this table is not recommended.

60502-1  IEC:2004+A1:2009 – 15 –
7 Assembly of multicore cables, inner coverings and fillers
The assembly of multicore cables depends on the rated voltage and whether a metallic layer is
applied to each core.
The following subclauses 7.1 to 7.3 do not apply to assemblies of sheathed single-core cables.
7.1 Inner coverings and fillers
7.1.1 Construction
The inner coverings may be extruded or lapped.
For cables with circular cores, except cables with more than five cores, a lapped inner covering
shall be permitted only if the interstices between the cores are substantially filled.
A suitable binder is permitted before application of an extruded inner covering.
7.1.2 Material
The materials used for inner coverings and fillers shall be suitable for the operating
temperature of the cable and compatible with the insulating material.
For halogen free cable
...