SIST HD 620 S1:1998/A1:2002
(Amendment)Distribution cables with extruded insulation for rated voltages from 3,6/6 (7,2) kV to 20,8/36 (42) kV
Distribution cables with extruded insulation for rated voltages from 3,6/6 (7,2) kV to 20,8/36 (42) kV
Superseded by HD 620 S2:2010
Energieverteilungskabel mit extrudierter Isolierung für Nennspannungen von 3,6/6 (7,2) kV bis 20,8/36 (42) kV
Câbles de distribution, à isolation extrudée, pour des tensions assignées de 3,6/6 (7,2) kV à 20,8/36 (42) kV inclus
Amendment to HD according to maintenance programme - Group 2
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST HD 620 S1:1998/A1:2002
01-april-2002
Amendment to HD according to maintenance programme - Group 2
Distribution cables with extruded insulation for rated voltages from 3,6/6 (7,2) kV to
20,8/36 (42) kV
Energieverteilungskabel mit extrudierter Isolierung für Nennspannungen von 3,6/6 (7,2)
kV bis 20,8/36 (42) kV
Câbles de distribution, à isolation extrudée, pour des tensions assignées de 3,6/6 (7,2)
kV à 20,8/36 (42) kV inclus
Ta slovenski standard je istoveten z: HD 620 S1:1996/A1:2001
ICS:
29.060.20 Kabli Cables
SIST HD 620 S1:1998/A1:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST HD 620 S1:1998/A1:2002
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SIST HD 620 S1:1998/A1:2002
HARMONIZATION DOCUMENT HD 620 S1/A1
DOCUMENT D'HARMONISATION (Volume I: Parts 1 to 5)
HARMONISIERUNGSDOKUMENT July 2001
ICS 29.060.20
English version
Distribution cables with extruded insulation for rated voltages
from 3,6/6 (7,2) kV to 20,8/36 (42) kV
Câbles de distribution, à isolation Energieverteilungskabel mit extrudierter
extrudée, pour des tensions assignées Isolierung für Nennspannungen
de 3,6/6 (7,2) kV à 20,8/36 (42) kV inclus von 3,6/6 (7,2) kV bis 20,8/36 (42) kV
This amendment A1 modifies the Harmonization Document HD 620 S1:1996; it was approved by
CENELEC on 2000-08-01. CENELEC members are bound to comply with the CEN/CENELEC Internal
Regulations which stipulate the conditions for implementation of this amendment on a national level.
Up-to-date lists and bibliographical references concerning such national implementation may be obtained on
application to the Central Secretariat or to any CENELEC member.
This amendment exists in three official versions (English, French).
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway,
Portugal, 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
© 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. HD 620 S1:1996/A1:2001 E
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HD 620 S1:1996/A1:2001
FOREWORD
This amendment to HD 620 S1:1996 has been prepared by WG9 of CENELEC TC20 "Electric Cables".
CENELEC TC20 confirmed at its Dublin meeting (April 1997) that the amendment should go to the Unique
Acceptance Procedure.
Part 1 has been completely re-issued, due to extensive changes to the tables of compounds, and to the
complete withdrawal of cable types with PVC insulation. Because of this withdrawal of PVC insulated cables,
Parts 3 and 4 are now designated "Spare". A list of additions and amendments to the particular sections of
Parts 5-9 is given in this Part 0.
NOTE During the preparation of this amendment, IEC 502 (4th edition) has been replaced by IEC 60502-2.
In general the updating of these references has not been included in this amendment unless a complete section has been introduced or
replaced. Users should refer to IEC 60502-2 for the most up-to-date information, but note that the clause numbers are not identical to those
in IEC 502 (4th edition).
The draft was submitted to the Unique Acceptance Procedure in September 1999 and was approved by
CENELEC as amendment A1 to HD 620 S1:1996 on 2000-08-01.
The following dates were fixed:
- latest date by which the existence of the amendment
has to be announced at national level (doa) 2001-02-01
- latest date by which the amendment has to be implemented
at national level by publication of a harmonized
national standard or by endorsement (dop) 2002-01-01
- latest date by which the national standards conflicting
with the amendment have to be withdrawn (dow) 2003-08-01
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HD 620 S1:1996/A1:2001
Contents
(HD 620 S1:1996 plus amendment A1)
(2)
PART 1 General requirements
(3)
PART 3 (Spare)
(3)
PART 4 (Spare)
PART 5 XLPE insulated single core cables, and single core pre-assembled cables
5-A Cables with PE (Type 5A-1) or PVC sheath (Type 5A-2)
(1)
5-B Cables with PE (Type 5B-1) or PVC sheath (Type 5B-2)
(2)
5-C Cables with PE (Type 5C-1) or PVC sheath (Type 5C-2)
5-D Cables with PE (Type 5D-1) or PVC sheath (Type 5D-2)
(2)
5-E-1 Cables with polyolefine compound sheath (Type 5E-1)
5-E-2 Bundle assembled cables with steel messenger core for overhead distribution and service MV
(Type 5E-3)
5-F Cables with aluminium conductors and PVC sheath (Type 5F-1), cables with aluminium
conductors and PE sheath with aluminium conductors and PE sheath, laid-up (Type 5F-2),
cables with aluminium conductors and PE sheath, laid-up around a bare-earth conductor
(Type 5F-3), cables with aluminium conductors and PE sheath, laid-up around a steel
messenger (Type 5F-4) and cables with copper conductors and PVC sheath (Type 5F-5)
5-G Cables with PVC sheath laid-up (Type 5G-1), cables with PVC sheath laid-up around an earth
conductor (Type 5G-2 and Type 5G-3), cables with PVC sheath laid around a messenger
(Type 5G-4) and cables with PVC sheath not laid-up (Type 5G-5)
5-H Cables with PE sheath (Type 5H)
(2)
5-J Cables with PE (Type 5J-1) or PVC sheath (Type 5J-2) or PVC flame retardant sheath
(Type 5J-3)
5-K Cables with PE (Type 5K-1) or PVC sheath (Type 5K-2)
(2)
5-L Cables with PVC sheath, laid-up (Type 5L-1) or not (Type 5L-2) around an additional
conductor
(1)
5-M Cables with PE sheath (Type 5M-1) and PVC sheath (Type 5M-2)
(1)
5-N Cables with PE sheath (Type 5N-1) or PVC sheath (Type 5N-2)
(1)
5-O-1 Single core XLPE insulated cables (Type 5O-1)
(1)
5-O-2 Single core XLPE insulated cables with lead sheath (Type 5O-2)
(3)
5-O-3 (Spare)
(1)
5-O-4 Single core XLPE insulated cables with wire screens and PE sheath (Type 5O-4)
(1)
5-O-5 Cables with alternative wire screens and PE sheath (Type 5O-5)
(1)
5-O-6 Single core XLPE insulated cables with wire screens and PVC sheath (Type 5O-6)
(1)
5-P Cables with PVC sheath laid-up around an earth conductor (Type 5P-1 and
Type 5P-2), cables with PVC sheath laid around a messenger (Type 5P-3)
_______________
(1)
A1 introduces some changes to the text
(2)
A1 completely revises the Particular Section
(3)
Item withdrawn by A1
(4)
A1 introduces new Section
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HD 620 S1:1996/A1:2001
PART 6 XLPE insulated three core cables
6-A Cables with PE (Type 6A-1) or PVC sheath (Type 6A-2)
(2)
6-C Cables with PE (Type 6C-1) or PVC sheath (Type 6C-2)
6-D Cables with PE (Type 6D-1) or PVC (Type 6D-2) sheath
6-F Cables with PVC sheath and individual copper screen (Type 6F-1),
cables with PE sheath and individual copper screen (Type 6F-2) and
cables with PE sheath and common copper screen (Type 6F-3)
(2)
6-J Cables with PE (Type 6J-1) or PVC sheath (Type 6J-2) or PVC flame retardant sheath
(Type 6J-3)
6-K Cables with PE (Type 6K-1) or PVC sheath (Type 6K-2)
(1)
6-M Cables with PE sheath (Type 6M-1) and PVC sheath (Type 6M-2)
(1)
6-N Cables with PE sheath (Type 6N-1) or PVC sheath (Type 6N-2)
(1)
6-O-1 3-core XLPE insulated cables (Type 6O-1)
(1)
6-O-2 3-core XLPE insulated cables with metallic armour and PE sheath (Type 6O-2)
(1)
6-O-3 3-core XLPE insulated cables with wire screen and PE screen (Type 6O-3)
PART 7 EPR insulated single core cables, and single core pre-assembled cables
(2)
7-E-1 Cables with polyolefine compound sheath (Type 7E-1)
7-E-2 Bundle assembled cables with steel messenger core for overhead distribution and service MV
(Type 7E-2)
(2)
7-I Cables with PVC sheath (Type 7I)
(1)
7-N Cables with PE sheath (Type 7N-1) or PVC sheath (Type 7N-2)
(1)
7-O-1 Single core EPR insulated cables (Type 7O-1)
(3)
7-O-2 (Spare)
(1)
7-O-3 Single core EPR insulated cables with wire screens and PE sheath (Type 7O-3)
(1)
7-O-4 Cables with alternative wire screens and PE sheaths (Type 7O-4)
PART 8 EPR insulated three core cables
(2)
8-I Cables with PVC sheath (Type 8I)
(1)
8-N Cables with PE sheath (Type 8N-1) or PVC sheath (Type 8N-2)
(1)
8-O-1 3-core EPR insulated cables (Type 8O-1)
(1)
8-O-2 3-core EPR insulated cables with metallic armour and PE sheath (Type 8O-2)
PART 9 HEPR insulated single core cables, and single core pre-assembled cables
(4)
9-E Cables with HEPR insulation and polyolefine compound sheath (Type 9E)
(2)
9-I-1 Cables with HEPR insulation, PE sheath and Alumoweld messenger (Aerial cables, Type 9I-1)
9-I-2 Cables with HEPR insulation and PVC sheath, single core and pre-assembled type (Type 9I-2)
_______________
(1)
A1 introduces some changes to the text
(2)
A1 completely revises the Particular Section
(3)
Item withdrawn by A1
(4)
A1 introduces new Section
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SIST HD 620 S1:1998/A1:2002
Page 1-1
HD 620 S1:1996/A1:2001
Part 1
HD 620 S1:1996/A1:2001
Distribution cables with extruded insulation for rated voltages
from (3,6/6 7,2) kV up to and including 20,8/36 (42) kV
Part 1: General requirements
Replace the complete part by the following:
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HD 620 S1:1996/A1:2001
Part 1
Contents
1 General .1-4
1.1 Scope .1-4
1.2 Object.1-4
2 Definitions .1-4
2.1 Definitions concerning the insulating and sheathing compounds.1-4
2.2 Definitions relating to the tests .1-5
2.3 Rated voltage .1-6
3 Marking.1-6
3.1 Indication of origin.1-6
3.2 Additional marking .1-7
3.3 Durability .1-7
3.4 Legibility .1-7
3.5 Common marking.1-7
3.6 Use of the name CENELEC.1-7
4 Construction of cables.1-7
4.1 Conductors .1-7
4.2 Insulation.1-8
4.3 Screening of cores.1-8
4.4 Assembly of cores.1-9
4.5 Fillers and binder tapes.1-9
4.6 Inner covering (bedding) .1-9
4.7 Inner sheath.1-10
4.8 Metallic coverings .1-11
4.9 Outer sheath.1-11
4.10 Earthing conductor.1-12
4.11 Messenger.1-12
5 Tests on completed cables.1-13
6 Sealing and packing.1-13
7 Current-carrying capacity.1-13
8 Guide to use and selection of cables .1-13
Tables 1-5 . 1-14
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HD 620 S1:1996/A1:2001
Part 1
References
Part 1 of HD 620 S1 incorporates by dated or undated reference, provisions from other publications. These
references are cited at the appropriate places in the text and the publications are listed hereafter. For dated
references, subsequent amendments to or revisions of any of these publications apply to Part 1 of
HD 620 S1 only when incorporated in it by amendment or revision. For undated references the latest edition
of the publication referred to applies.
EN 60811 Insulating and sheathing materials of electric cables – Common test methods
HD 383 Conductors of insulated cables (Endorsing IEC 60228 and IEC 60228A)
HD 405 Tests on electric cables under fire conditions (Endorsing IEC 60332)
HD 605 Electric cables – Additional test methods
IEC 60229 Tests on cable oversheaths which have a special protective function and are
applied by extrusion
IEC 60287 Electric cables – Calculation of the current rating
IEC 60840 Tests for power cables with extruded insulation for rated voltages above 30 kV
(U = 36 kV) up to 150 kV (U = 170 kV)
m m
IEC 60885 Electrical test methods for electric cables.
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HD 620 S1:1996/A1:2001
Part 1
1 General
1.1 Scope
HD 620 applies to cables with extruded insulation and for rated voltages U /U(U ) from 3,6/6 (7,2) kV up to
o m
20,8/36(42) kV used in power distribution systems of voltages not exceeding the maximum r.m.s value of the
system voltage U .
m
This Part (Part 1) specifies the general requirements applicable to these cables, unless otherwise specified
in the particular sections of this HD.
Test methods specified are given EN 60811, HD 383, HD 405, HD 605 and in IEC 60229, IEC 60840,
IEC 60885-2 and IEC 60885-3.
NOTE 1 HD 405 is currently under revision. Parts 1 and 2 will be re-issued within EN 50265, and Part 3 as EN 50266.
Attention should be drawn to the fact that a significant number of sections include references to long term
tests which are collected in HD 605. These long-term tests are considered as necessary and reflect the best
available knowledge for the existing cable design. They are related to specific designs and different
philosophies concerning adequate measures against the influence of water. However it is the firm intention
to reduce this large number of different tests, but more experience should be gained before starting to
rationalise this important matter.
The particular types of cables are specified in Parts 5 to 9.
NOTE 2 Cables originally in Parts 3 and 4 have now been withdrawn.
1.2 Object
The objects of this Harmonisation Document are:
− to standardise cables that are safe and reliable when properly used, in relation to the technical
requirements of the system of which they form a part;
− to state the characteristics and manufacturing requirements which have a direct or indirect
bearing on safety;
− and to specify methods for checking conformity with those requirements.
2 Definitions
2.1 Definitions concerning the insulating and sheathing compounds
2.1.1 Insulating and sheathing compounds
The types of insulating and sheathing compounds covered by this HD are listed below, together with their
abbreviated designations:
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HD 620 S1:1996/A1:2001
Part 1
Table 2.1.1 – Insulating and sheathing compounds
Insulating and sheathing compounds See:
Insulation a) Thermoplastic:
(spare)
b) Cross-linked:
Insulating compounds based on:
- Cross-linked polyethylene (XLPE) Table 2A
- Ethylene propylene rubber (EPR) Table 2B
- Hard ethylene propylene (HEPR) Table 2C
rubber
Sheathing a) Elastomeric
(under consideration) (Table 3)
b) Thermoplastic:
Sheathing compounds based on:
- Polyvinyl chloride (PVC) Table 4A
- Polyethylene (PE) Table 4B
- Polyolefine (PO) Table 4C
2.1.2 Type of compound
The category in which a compound is placed according to its properties is determined by specific tests. The
type designation is not directly related to the composition of the compound.
2.2 Definitions relating to the tests
NOTE Tests classified as Sample (S) or Routine (R) may be required as part of any type approval schemes.
2.2.1 Type tests (Symbol T)
Tests required to be made before supplying a type of cable covered by this HD on a general commercial
basis in order to demonstrate satisfactory performance characteristics to meet the intended application.
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 material, design or type of manufacturing process which might change the
performance characteristics.
2.2.2 Sample tests (Symbol S)
Tests made on samples of completed cable, or components taken from a completed cable adequate to verify
that the finished product meets the design specifications.
2.2.3 Routine tests (Symbol R)
Tests made on all production cable lengths to demonstrate their integrity.
2.2.4 Tests after installation
Test intended to demonstrate the integrity of the cable and its accessories as installed.
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HD 620 S1:1996/A1:2001
Part 1
2.3 Rated voltage
The rated voltage of a cable is the reference voltage for which the cable is designed, and which serves to
define the electrical tests.
The rated voltage is expressed by the combination of the following values U /U(U ) expressed in kV.
o m
U is the r.m.s value between any phase conductor and earth (metal covering of the cable).
o
U is the r.m.s value between any two phase conductors of a multicore cable or of a system of single-core
cables.
U is the maximum r.m.s value of the highest system voltage for which the equipment may be used.
m
The standard rated voltages U /U(U ), in kV r.m.s., of the cables in this HD are as follows:
o m
U /U(U ) = 3,6/6(7,2) - 3,8/6,6(7,2) - 6/10(12)
o m
6,35/11(12) - 8,7/15(17,5) - 12/20(24)
12,7/22(24) - 15/20(24) - 15/25(30)
18/30(36) - 19/33(36) - 20,8/36(42)
In an alternating current system, the rated voltage of a cable shall be at least equal to the nominal voltage of
the system for which it is intended. If used in d.c. systems, the maximum voltage has to be specified in the
particular sections.
3 Marking
3.1 Indication of origin
Cables shall be provided with an identification of origin consisting of the continuous marking of the
manufacturer’s name or trademark, or (if legally protected) identification number by one of the two following
alternative methods:
a) printed tape within the cable;
b) printing, indenting or embossing on the outer surface of the cable.
3.1.1 Continuity of marks
Unless otherwise specified in the particular sections, each specified mark shall be regarded as continuous if
the distance between the end of the mark and the beginning of the next identical mark does not exceed:
− 550 mm if the marking is on the outer surface of the cable,
− 275 mm if the marking is on a tape.
NOTE A ‘specified mark’ is any mandatory mark covered by this Part of the HD or by the particular requirements of Part 3 onwards of
this HD.
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HD 620 S1:1996/A1:2001
Part 1
The diagram below shows an example of the marking as used on the outer surface of the cable, where the
word ‘ORIGIN’ is for the mandatory information required by the subclause 3.1, and ‘XYZ’ is one of any other
mandatory marks.
3.2 Additional marking
Additional marking requirements may be specified in the particular sections.
3.3 Durability
Printed markings shall be durable. Durability shall be checked by the test given in subclause 2.5.4 of
HD 605.
The printed legend shall be legible after carrying out the test.
3.4 Legibility
All markings shall be legible. Printed markings shall be in contrasting colours.
3.5 Common marking
Under consideration
3.6 Use of the name CENELEC
The name CENELEC, in full or abbreviated, shall not be marked directly on or in the cables.
4 Construction of cables
Compliance with the requirements specified in subclauses 4.1 to 4.11 and in the particular sections of this
HD shall be checked by inspection and by measurement according to the test methods in the documents
listed in the particular sections of this HD.
4.1 Conductors
4.1.1 Material
Conductors shall be either plain or metal-coated annealed copper or plain or metal-sheathed aluminium
(earthing conductor) or aluminium alloy in accordance with HD 383 and the particular requirements in the
particular sections of this HD.
Conductors shall be either circular or sector in shape, and of solid metal or stranded.
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HD 620 S1:1996/A1:2001
Part 1
4.1.2 Electrical resistance
The resistance of each conductor at 20ºC shall be in accordance with the requirements in HD 383 for the
given class of conductor.
4.2 Insulation
4.2.1 Material
The insulation shall be extruded solid compound of one of the types listed in subclause 2.1.1 and as
specified for each type of cable in the particular sections of this HD.
The test requirements for the insulating compounds are specified in Tables 2A, 2B and 2C and the reference
to the test methods are specified in the particular sections.
4.2.2 Application
The insulation shall be applied by an extrusion process and shall form a compact and homogeneous body.
Special requirements may be given in the particular sections.
It shall be so applied that it fits closely on the conductor or conductor screen, if any, and it shall be possible
to remove the insulation, including conductor screen or insulation screen if bonded.
4.2.3 Thickness
The mean value of the thickness of the insulation, excluding semi-conducting layers, shall not be less than
the value specified in the particular sections.
However, the thickness at any place may be less than the specified value provided that the difference does
not exceed 0,1 mm + 10% of the specified value.
Compliance shall be checked by the test method given in HD 605, subclause 2.1.1.
4.2.4 Mechanical properties before and after ageing
The insulation shall have appropriate mechanical characteristics.
Compliance shall be checked by carrying out the tests specified in Tables 2A, 2B and 2C.
4.2.5 Additional properties
These are specified in the particular sections.
4.3 Screening of cores
4.3.1 Core screening
Screening of cores, if required (see subclause 4.3.4), shall consist of conductor screening and insulation
screening.
4.3.2 Conductor screening
The conductor screening shall consist of a non-metallic semi-conducting part and shall fulfil the requirements
specified in the particular sections.
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HD 620 S1:1996/A1:2001
Part 1
4.3.3 Insulation screening
The insulation screen shall consist of a non-metallic semi-conducting part in combination with a metallic part.
The non-metallic part shall be applied directly upon the insulation of each core and in intimate contact, and
shall fulfil the requirements specified in the particular sections.
The metallic part shall be applied over the individual cores or over the core assembly and shall comply with
subclause 4.8.
4.3.4 Screening limits for the cores
Unless otherwise specified the screening limits for the cores are:
− compulsory for all cables with XLPE insulation
− compulsory for cables with EPR or HEPR insulation and U /U(U ) above 3,6/6 (7,2) kV.
o m
4.4 Assembly of cores
In three-core cables, the cores shall be laid-up. The direction of lay is specified in the particular sections.
Auxiliary cores, if any, shall be laid-up in the interstices between main cores. Allowed number and
requirements thereof are specified in the particular sections.
4.5 Fillers and binder tapes
For each type of cable, the particular sections detail whether that cable includes fillers or tapes, or whether
the sheath or inner covering may penetrate between the cores, thus forming a filling. It shall be possible to
remove fillers without damage to cores.
A centre filler may be used in three-core cables, and the assembly of cores and fillers may be held together
by a binder tape, or tapes.
Fillers and binder tapes, if any, shall be composed of a suitable material.
For cables with core screening having a concentric metallic part over the assembly, the fillers may be semi-
conducting.
When fillers or binder tapes are applied, they shall be compatible with the other components. Compliance
with this requirement shall be checked by the test specified in subclause 8.1.4 of EN 60811-1-2 for the
appropriate maximum conductor temperature in normal operation, unless stated otherwise in the particular
sections.
4.6 Inner covering (bedding)
The inner covering, if any, may be extruded or lapped, or a combination of the two, as specified in the
particular section.
4.6.1 Material
The material used for inner coverings shall be suitable for use at the maximum conductor temperature of the
cable in normal operation and compatible with the cable components with which it is in contact.
For radial field cables having a concentric metallic part over the assembly, the inner covering shall be semi-
conducting.
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HD 620 S1:1996/A1:2001
Part 1
4.6.2 Application
The extruded inner covering shall surround the core assembly completely and may penetrate the spaces
between them. The extruded inner covering shall be separable without damage to the cores.
Lapped covering shall consist of one or more layers of tape covering the entire outer surface of the core
assembly.
For each type of cable, the particular sections indicate whether that cable includes an extruded or lapped
inner covering, or a combination of these.
4.6.3 Thickness
Unless otherwise specified in the particular sections the thickness of the extruded or lapped inner covering
need not be checked by measurement.
4.7 Inner sheath
An inner sheath may be specified in the particular sections.
4.7.1 Material
The material used for the extruded inner sheath shall be suitable for use at the maximum conductor
temperature of the cable in normal operation and compatible with the cable components with which it is in
contact.
Test requirements and references to test methods for the inner sheath are given in Tables 3, 4A, 4B and 4C
unless stated otherwise in the particular sections.
4.7.2 Application
The inner sheath shall be extruded in a single layer. The sheath may be applied over an inner covering or
directly over the core assembly or over a collective metallic screen. The sheath shall not adhere to the
cores.
4.7.3 Thickness
The mean value of the thickness of the inner sheath shall be not less than the specified value for each type
and size of cable in the particular sections.
However, unless otherwise specified in the thickness at any place may be less than the specified value
provided that the difference does not exceed 0,2 mm+ 20% of the specified value.
Compliance shall be checked by the test method given in HD 605, subclause 2.1.2.
4.7.4 Mechanical properties before and after ageing
The sheath shall have appropriate mechanical characteristics.
Compliance shall be checked by carrying out the tests given in Tables 3, 4A, 4B and 4C unless stated
otherwise in the particular sections.
4.7.5 Other properties
Other properties are specified in the particular sections.
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HD 620 S1:1996/A1:2001
Part 1
4.8 Metallic coverings
Cables shall have a metallic layer surrounding the cores individually or collectively.
The following types of metallic covering may be specified
...
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