As NZS 1429.2200X Electric Cables—Polymeric Insulated for Working Voltages Above 19 - 33 (3.6) KV Up to and Including 87 - 150 (170) KV

Electric cablesPolymeric insulated Part Title: For working voltages above 19/33 (36) kV up to and including 87/150 (170) kV Designation: AS/NZS 1429.2:200X Part Number: 2 Supersedes Standard No: AS/NZS 1429.2:1998 AustralianORJoint: Australian/New Zealand Creation Date: 2005-08-22 Revision Date: 2008-06-19 Issue Date: JUNE 2008 Committee Number: EL-003 Committee Title: Electric Wires and Cables Subcommittee Number: EL-003-02 Subcommittee Title: Electric Cables for Utilities Project Manager: Alan Ly PMs Email Address: [email protected] WP Operator: Alan Project Number: 6731 Combined Procedure?: No Committee Doc No.: D0006 Supersedes Committee Doc No.:

D0005

Stage: POSTAL BALLOT Committee Reps: Australasian Railway Association

Australian Electrical and Electronic Manufacturers Association Australian Industry Group Canterbury Manufacturers Association New Zealand Department of Defence (Australia) Department of Primary Industries, Mine Safety (NSW) Electrical Contractors Association of New Zealand Electrical Regulatory Authorities Council Energy Networks Association Engineers Australia Ministry of Economic Development (New Zealand)

Additional Interests: Click here and type organisation names using shift return for new line Product Type JS Document Status Current Document Availability Private History: First published as AS/NZS 1429.2:1998.

Second edition 200X. Public Enquiry

DR Number: DR 07213 Publication Date 20 April 2007 Close of Comment Date 22 June 2007 DR Price Code Click here and type DR Price Code PMs Facsimile No: (02) 8206 6021

Final Publication Date Approved: Click here and type Date approved Date Approved by SNZ Click here and type Date approved by SNZ Final Publication Date: Click here and type Date published

ISBN: 0 7337 Click here and enter digits in XXXX X format ICS Code: Click here and type CS Code Synopsis Publication Click here and type Synopsis for Publication

DraftFor Committee Purposes Only D0006

POSTAL BALLOT DRAFT Issued: JUNE 2008

Project No: 6731

STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND

Committee EL-003 Electric Wires and Cables

Subcommittee EL-003-02Electric Cables for Utilities

DRAFT

Australian/New Zealand Standard

Electric cablesPolymeric insulated

INTRODUCTORY NOTE

There are still outstanding issues which needs to be resolved, before sending out for Committee Ballot.

DRAFT ONLY 2 DRAFT ONLY

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PREFACE This Standard was prepared by the Joint Standards Australia/Standards New Zealand Committee EL-003, Electric Wires and Cables, to supersede AS/NZS 1429.2:1998, Electric cablesPolymeric insulation, Part 2: For working voltages above 19/33 (36) kV up to and including 76/132 (145) kV.

The objective of this Standard is to specify requirements for single-core cross-linked polyethylene insulated cables for fixed installations operating at voltages above 19/33 (36) kV up to and including 87/150 (170) kV.

In the preparation of this Standard, consideration was given to the following publications and acknowledgment is made of the assistance received:

IEC

60229 Tests on cable oversheaths which have a special protective function and areapplied by extrusion

60502 Extruded solid dielectric insulated power cables for rated voltages from 1 kV up to 30 kV

60811 Common test methods for insulating and sheathing materials of electric cables(all parts)

AEIC

CS7 Specifications for crosslinked polyethylene insulated shielded power cablesrated 69 through 138 kV

One type of insulation compound is specified in this Standard, namely insulation comprising cross-linked polyethylene (XLPE).

Although the Standard provides tables of insulation thicknesses and the necessary information to establish precisely the dimensions of the cable protective coverings, no cable dimension tables are provided owing to the variety of cable constructions that could affect such dimensions.

This Standard differs from the previous edition in the following significant ways:

(a) The voltage range has changed with the deletion of the 64/110 (123) kV type and the addition of a 87/150 (170) kV type.

(b) The conductors now comply with IEC 60228.

(c) The types of metallic moisture barrier included have been increased.

(d) An increased range of oversheath materials, referenced to AS/NZS 3808, has been included.

(e) Optional outer conductive coatings and fibre optic components have been included.

(f) Testing has been generally referenced to AS/NZS 60840 with additional tests only being included in a table of tests.

The terms normative and informative have been used in this Standard to define the application of the appendix to which they apply. A normative appendix is an integral part of a Standard, whereas an informative appendix is only for information and guidance.

Statements expressed in mandatory terms in notes to tables and figures are deemed to be requirements of this Standard.


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CONTENTS

Page

SECTION 1 SCOPE AND GENERAL 1.1 SCOPE......................................................................................................................... 4 1.2 REFERENCED DOCUMENTS................................................................................... 4 1.3 DEFINITIONS............................................................................................................. 5 1.4 VOLTAGE DESIGNATION ....................................................................................... 6 1.5 MAXIMUM CONDUCTOR TEMPERATURE .......................................................... 7

SECTION 2 CONSTRUCTION 2.1 GENERAL................................................................................................................... 8 2.2 CONDUCTORS .......................................................................................................... 8 2.3 CONDUCTOR SCREEN............................................................................................. 8 2.4 INSULATION ............................................................................................................. 9 2.5 EXTRUDED INSULATION SCREEN...................................................................... 10 2.6 WATER BLOCKING................................................................................................ 11 2.7 METALLIC MOISTURE BARRIER ........................................................................ 11 2.8 METALLIC WIRE SCREEN (OPTIONAL) ............................................................. 13 2.9 BINDERS AND BARRIER TAPES .......................................................................... 14 2.10 OVERSHEATH......................................................................................................... 14 2.11 PROTECTION FROM INSECT ATTACK (OPTIONAL) ........................................ 15 2.12 OUTER CONDUCTIVE COATING (OPTIONAL) .................................................. 15 2.13 FIBRE OPTIC COMPONENTS (OPTIONAL) ......................................................... 15 2.14 CABLE IDENTIFICATION ...................................................................................... 16 2.15 METRE MARKING ON CABLE (OPTIONAL)....................................................... 16 2.16 PREPARATION FOR DELIVERY ........................................................................... 16 2.17 MARKING OF DRUMS ........................................................................................... 16

SECTION 3 TESTS 3.1 GENERAL................................................................................................................. 17 3.2 SELECTION OF SAMPLES ..................................................................................... 17 3.3 RE-QUALIFICATION TESTS.................................................................................. 19

APPENDICES A PURCHASING GUIDELINES.................................................................................. 21 B THE FICTITIOUS CALCULATION METHOD FOR THE DETERMINATION OF

THE DIMENSIONS OF INSULATION SCREEN AND PROTECTIVE COVERINGS ............................................................................................................ 22

C RECOMMENDED DIAMETER OF DRUM BARREL AND INSTALLATION BENDING RADIUS FOR CABLES ......................................................................... 25

D FREQUENCY OF SAMPLE TEST SELECTION AND RETEST PROCEDURE FOR SAMPLE TESTS .............................................................................................. 26

E ROUNDING OF NUMBERS .................................................................................... 27 F GUIDE TO THE SELECTION OF ACCESSORIES FOR HV CABLES WITH

EXTRUDED INSULATION ..................................................................................... 28 G TESTS AFTER INSTALLATION............................................................................. 33


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STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND

Australian/New Zealand Standard Electric cablesPolymeric insulated

Part 2: For working voltages above 19/33 (36) kV up to and including 87/150 (170) kV

S E C T I O N 1 S C O P E A N D G E N E R A L

1.1 SCOPE

This Standard specifies requirements for single-core cross-linked polyethylene (XLPE) insulated cables for fixed installations for electricity supply.

NOTES: 1 Optional requirements for metallic wire screen, the protection from insect attack, outer

conductive coating, inclusion of fibre optic elements, and metre marking on cable, are provided in Clause 2.8 and Clauses 2.11 to 2.15.

2 The full list of customer nominated requirements is given in Appendix A.

1.2 REFERENCED DOCUMENTS

The following documents are referred to in this Standard:

AS 1660 Test methods for electric cables, cords and conductors 1660.2.1 Part 2.1: Insulation, extruded semi-conductive screens and non-metallic

sheathsMethods for general application 1660.2.5 Part 2.5: Insulation, extruded semi-conductive screens and non-metallic

sheathsMethods specific to cables above 1 kV 1660.3 Part 3: Electrical tests

2848 Aluminium and aluminium alloys 2848.1 Part 1: Wrought products

3983 Metal drums for insulated electric cables and bare conductors

AS/NZS 1125 Conductors in insulated electric cables and flexible cords

2857 Timber drums for insulated electric cables and bare conductors

2893 Electric cablesLead and lead alloy sheathsComposition

3808 Insulating and sheathing materials for electric cables

60840 Power cables with extruded insulation and their accessories for rated voltagesabove 30 kV (Um = 36 kV) up to 150 kV (Um = 170 kV)Test methods and requirements

IEC 60228 Conductors of insulated cables


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1.3 DEFINITIONS

For the purposes of this Standard, the relevant definitions in the referenced Standards and those below apply.

1.3.1 Approximate value

A value which is neither guaranteed nor checked.

1.3.2 Conductor screen

A layer or layers of non-metallic semiconductive material applied directly over the conductor.

1.3.3 Core (of a cable)

An assembly comprising a conductor, semiconductive conductor screen, insulation and semiconductive insulation screen.

1.3.4 Fictitious values

Values calculated according to an equation based only on the cross-sectional area of a conductor and specified component dimensions, and which ignores conductor shape, construction, degree of compaction of conductors and the possibility of components having dimensions other than specified (see Appendix A).

1.3.5 Gross cross-sectional area

In relation to the metallic screen, the product of the calculated cross-sectional area of one screen wire based on its nominal diameter, multiplied by the total number of screen wires in the cable.

1.3.6 Insulation screen

A layer or layers of non-metallic semiconductive material applied directly over the insulation.

1.3.7 Length of lay

In relation to the metallic screen, the axial distance between successive turns of the helix of a screen wire.

1.3.8 Maximum conductor temperature

The maximum temperature resulting from the combined effect of all contributing thermal conditions. It varies depending on the mode of operation and is limited to the values specified in Table 1.1.

1.3.9 Moisture barrier

A means of preventing radial moisture ingress to the cable core.

1.3.10 Nominal value

A value by which a quantity is designated and which is often used in tables. Usually, in this Standard, nominal values give rise to values to be checked by measurements taking into account specified tolerances.

1.3.11 Non-hygroscopic

When applied to a material, means that the material after being preconditioned in an oven at 50 5C for 24 1 h and allowed to cool in a desiccator, does not absorb more than 5 % by weight of moisture during a 48 h treatment in a relative humidity of 95 4 % at a temperature of 20 5C.

1.3.12 Qualification test report

A report of results obtained from all routine, sample and type tests.


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1.3.13 Re-qualification tests

Tests made by the manufacturer on an already qualified range of cables following any changes in critical cable component materials or the method of cable manufacture.

1.3.14 Routine tests

Tests made by the manufacturer on each manufactured length of cable to check that each length meets the specified requirements.

1.3.15 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 meet the specified requirements.

1.3.16 Shall

Indicates that a statement is mandatory.

1.3.17 Should

Indicates a recommendation.

1.3.18 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.

1.3.19 Water-blocking, longitudinal

Prevention or reduction of water migration along the length of the cable. This may consist of design options in the area of the metallic screen and/or the conductor.

1.3.20 Water-blocking, radial

Prevention or reduction of water ingress towards the insulation by permeation through the outer part of the cable.

1.4 VOLTAGE DESIGNATION

Indication of the rated voltages shall be expressed in the form U0/U (Um)

where

U0 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

Um is the maximum r.m.s. power frequency voltage between any two phase conductors for which cables and accessories are designed. It is the highest voltage that can be sustained under normal operating conditions at any time and at any point in a system. It excludes temporary voltage variations due to fault conditions and sudden disconnection of large loads.

is the maximum value of the highest system voltage for which the equipment may be used (see IEC 60038)

The ranges of rated operating voltages (U0/U (Um) recognized for the purposes of this Standard are 38/66 (72.5) kV, 76/132 (145) kV and 87/150 (170) kV.


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1.5 MAXIMUM CONDUCTOR TEMPERATURE

The maximum conductor temperature of cables for different modes of operation is specified in Table 1.1.

TABLE 1.1

MAXIMUM CONDUCTOR TEMPERATURE FOR DIFFERENT MODES OF OPERATION

Continuous or cyclic operation

C

Emergency operation

C

Short circuit condition (5 s maximum duration)

C

90 105 250

NOTES: 1 The maximum conductor temperatures specified are based upon the properties of

the insulation material but in practice may need to be derated to take account of

(a) joints and terminations; and

(b) installation conditions, such as proximity to other circuits and services.

2 The emergency operation temperature is applicable for an average, over several years, of not more than one period per year. No period should exceed 36 h and there should be no more than three periods in any 12 consecutive months.


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S E C T I O N 2 C O N S T R U C T I O N

2.1 GENERAL

The construction shall comprise cross-linked polyethylene insulated single-core cables as described in Clauses 2.2 to 2.13. A typical cable construction is illustrated in Figure 1.

FIGURE 1 A TYPICAL CABLE CONSTRUCTION ARRANGEMENT

2.2 CONDUCTORS

Conductors shall be circular and aluminium or plain copper or tinned copper, complying with the requirements of IEC 60228 or AS/NZS 1125.

In order to reduce the maximum electric stress at the conductor screen surface, the minimum conductor size covered by this Standard is 95 mm2.

Conductors shall be stranded compacted or Milliken type.

2.3 CONDUCTOR SCREEN

2.3.1 Material and application

All cables shall have an extruded, cross-linked, semiconductive screen applied on the conductor. A non-hygroscopic semiconductive tape may be applied as part of the conductor screen and, where used, shall be applied directly on the conductor, preceding the extruded layer.

2.3.2 Thickness

The minimum thickness at any point of the extruded layer of conductor screen, determined by the method specified in AS/NZS 1660.2.1 for measurement of insulation thickness, shall be not less than 0.8 mm.

2.3.3 Removal from conductor

The conductor screen shall be readily removable from the conductor.


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2.3.4 Outer surface

The outer surface of the conductor screen shall be free of irregularities larger than those permitted in Table 3.1.

2.3.5 Tests

Tests on the conductor screen shall be made as specified in Table 3.1. The category of each test shall be as specified in Table 3.1.

2.3.6 Criteria

The conductor screen in the completed cable shall comply with the requirements specified in Table 3.1.

2.4 INSULATION

2.4.1 Material

Insulation shall be XLPE and shall comply with the requirements of AS/NZS 60840.

2.4.2 Application

The insulation shall be homogeneous and shall bond to the conductor screen so that it is not possible to separate the two without damage at their interface. For cables with voltages above 38/66 (72.5) kV, the insulation shall be applied by the extrusion process simultaneously with the semiconductive conductor and insulation screens, within the one crosshead. For 38/66 (72.5) kV cables, dual tandem extrusion process may be used. The dry cure process shall be used for all cables.

2.4.3 Thickness

The nominal insulation thickness (ti), and the minimum insulation thickness at any point shall be not less than the value specified in Table 2.1. The values for the minimum thickness at any point are derived from the equation:

0.90 ti 0.10 mm.

2.4.4 Concentricity

The thickness of insulation shall be measured at the thickest point (tmax) and the thinnest point (tmin) and the following concentricity requirement shall be met.

15.0max

minmax t

t - t


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TABLE 2.1

INSULATION THICKNESS

1 2 3 4 5 6 7

Nominal insulation thickness (ti) and minimum insulation thickness at any point for cable rated voltages of

38/66 (72.5) kV

mm

76/132 (145) kV

mm

87/150 (170) kV

mm

Nominal conductor

cross-sectional

area

mm2 Min. point

ti Min. point

ti Min. point

ti

95 120 150

11.7 11.7 10.7

13.0 13.0 12.0

16.1

18.0

185 240 300

10.7 10.7 9.8

12.0 12.0 11.0

16.1 16.1 16.1

18.0 18.0 18.0

19.7 18.8 18.8

22.0 21.0 21.0

400 500 630

9.8 9.8 9.8

11.0 11.0 11.0

16.1 16.1 16.1

18.0 18.0 18.0

18.8 18.8 18.8

21.0 21.0 21.0

800 1 000 1 200

8.9 8.9 8.9

10.0 10.0 10.0

16.1 16.1 16.1

18.0 18.0 18.0

17.9 17.9 17.9

20.0 20.0 20.0

1 600 2 000

8.9 8.9

10.0 10.0

16.1 16.1

18.0 18.0

17.9 17.9

20.0 20.0

2.4.5 Tests

Tests on the insulation shall be as specified in Table 3.1. The category of each test shall be as specified in Table 3.1.

2.4.6 Criteria

The insulation in the completed cable shall comply with the requirements specified in Table 3.1.

2.5 EXTRUDED INSULATION SCREEN


The screen shall consist of a layer of extruded, cross-linked, semiconductive compound applied directly over the insulation.

2.5.2 Thickness

The minimum thickness at any point of the extruded layer of insulation screen, determined by the method specified in AS/NZS 1660.2.1 for measurement of insulation thickness, shall be not less than 0.8 mm.

2.5.3 Requirements for stripping the insulation screen

The insulation screen shall be fully bonded to the insulation so removal shall be by tools that cut away the screen.

2.5.4 Tests

Tests on the insulation screen shall be made as specified in Table 3.1. The category of each test shall be as specified in Table 3.1.


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2.5.5 Criteria

The insulation screen in the completed cable shall comply with the requirements specified in Table 3.1.

2.6 WATER BLOCKING

2.6.1 General

Water-blocking measures shall be taken to restrict water permeation along the cable (between the core and metallic moisture barrier) in the event of damage to the cable moisture barrier (see AS/NZS 60840).


Water blocking shall be achieved by non-biodegradable, water-swellable semi-conductive tape(s) applied under the metallic moisture barrier.

The tape(s) shall be readily removable from the core.

Hygroscopicity is an essential characteristic of a swellable water-blocking material. Where water-blocking materials are used, these materials are exempt from the requirement for non-hygroscopic materials.

NOTE: Some barrier or binder tapes used in conjunction with water-blocking tapes may reduce the effectiveness of water-blocking measures.

2.7 METALLIC MOISTURE BARRIER

2.7.1 General

Cables shall be provided with a radial moisture barrier, such as one of the following types:

(a) Lead alloy sheath.

(b) Corrugated aluminium.

(c) Longitudinally welded smooth aluminium sheath.

(d) Corrugated copper.

(e) Corrugated stainless steel.

(f) Metal foil laminates.

2.7.2 Nominal thickness

The nominal thickness of the moisture barrier shall be provided by the supplier and shall not be less than the value stated in the appropriate Clause, 2.7.3 to 2.7.8.

The thickness of moisture barrier is very dependent on the type used and may be calculated to meet earth-fault current requirements.

Where the moisture barrier does not meet the earth-fault current requirements then a metallic screen shall be added in the cable design.

2.7.3 Lead alloy sheath

2.7.3.1 Material

The sheath shall be lead alloy E in accordance with AS/NZS 2893.

2.7.3.2 Application

The lead alloy sheath shall be applied over the water blocking tapes by the continuous extrusion process and shall be readily removable.

2.7.3.3 Thickness

In no case shall the nominal thickness of the lead alloy sheath be less than 1.5 mm.


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The minimum thickness at any point of the lead alloy sheath, shall not fall below the nominal thickness (Tm) by more than 5 % of the nominal thickness plus 0.1 mm, i.e.

minimum thickness = 0.95 Tm 0.10 mm.

2.7.3.4 Tests

All tests on the lead alloy sheath shall be in accordance with Table 3.1. The category of each test shall be as specified in Table 3.1.

2.7.3.5 Pass criteria

The lead alloy sheath in the completed cable shall comply with the appropriate requirements of Table 3.1.

2.7.4 Corrugated extruded aluminium sheath

2.7.4.1 Material

The sheath shall be aluminium of 99.6% minimum purity having an elongation of 16% minimum.

NOTE: Reference to test methods is under consideration.

2.7.4.2 Application

The sheath shall be corrugated, of uniform thickness, homogeneous construction, seamless, free from defects, porosity and intercrystalline fracture. A layer of bitumen or other suitable compound, incorporating corrosion inhibitors, shall be applied over the aluminium sheath for corrosion protection and to provide a moisture seal with the oversheath.

2.7.4.3 Thickness

In no case shall the nominal thickness of aluminium sheath be less than 2.0 mm.

The minimum thickness at any point of the aluminium sheath, shall not fall below the nominal thickness (Tm) by more than 15% of the nominal thickness plus 0.1 mm, i.e.

minimum thickness = 0.85 Tm 0.10 mm.

2.7.4.4 Tests

All tests on the aluminium sheath shall be in accordance with Table 3.1. The category of each test shall be as specified in Table 3.1.

2.7.4.5 Pass criteria

The aluminium sheath in the completed cable shall comply with the appropriate requirements of Table 3.1.

2.7.5 Longitudinally welded aluminium sheath

2.7.5.1 Material

The sheath shall be of aluminium alloy 1050, temper O material complying with AS 2848.1.

2.7.5.2 Application

The aluminium sheath shall be longitudinally seam welded. It shall be applied over the water blocking tapes. The aluminium may either be a smooth sheath or it may be corrugated. The outer surface of the smooth sheath shall be treated in order to enable bonding to the oversheath. A layer of bitumen or other suitable compound, incorporating corrosion inhibitors, shall be applied over the corrugated aluminium sheath for corrosion protection and to provide a moisture seal with the oversheath.

2.7.5.3 Thickness

The nominal thickness of aluminium sheath shall not be less than 0.9 mm.


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2.7.6 Corrugated copper sheath

2.7.6.1 Material

The sheath shall be copper of 99.6% minimum purity.

2.7.6.2 Application

The sheath shall be longitudinally seam welded, corrugated, of uniform thickness, homogeneous construction and free from defects.

2.7.6.3 Thickness

The nominal thickness of copper sheath shall not be less than 0.9 mm.

2.7.7 Corrugated stainless steel sheath

2.7.7.1 Material

The sheath shall be stainless steel Grade 304 or Grade 316 in accordance with AS 2837.

2.7.7.2 Application

The sheath shall be longitudinally seam welded, corrugated, of uniform thickness, homogeneous construction, free from defects.

2.7.7.3 Thickness

The nominal thickness of stainless steel sheath shall not be less than 0.8 mm.

2.7.8 Metal foil laminates

2.7.8.1 Material

The metal foil may be either aluminium or copper. The foil shall be single side polymer coated in order to enable bonding to the oversheath.

2.7.8.2 Application

The metal foil shall be longitudinally applied with overlap and sealed.

2.7.8.3 Thickness

The nominal thickness of the metal foil shall be not less than 0.15 mm for aluminium and 0.08 mm for copper. Unless otherwise specified by the customer, the cross-sectional area of the foil may be taken into account when calculating the short-circuit rating of the metallic screen.

2.8 METALLIC WIRE SCREEN (OPTIONAL)

2.8.1 General

The metallic wire screen shall be of adequate cross-sectional area, calculated to ensure that, under fault conditions, the transient temperature of the screen does not exceed 250C.

2.8.2 Material

The metallic wire screen shall comprise plain annealed copper wires, generally complying with AS/NZS 1125. All wires shall be of the same nominal diameter and in no case less than 0.80 mm. Where fibre optics are included within the metallic wire screen construction, larger size wires are allowed on both sides of the fibre optic to protect it from damage. See Clause 2.13.

2.8.3 Application

The wires shall be helically applied.


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2.8.4 Tests

Tests on the metallic wire screen and the category of each test shall be as specified in Table 3.1.

2.8.5 Pass criteria

The metallic wire screen in the completed cable shall comply with the appropriate requirements specified in Table 3.1.

2.9 BINDERS AND BARRIER TAPES

Any binders and barrier tapes shall be compatible with the cable components with which they are in contact. Where the tape is non-water blocking it shall be non-hygroscopic.

NOTE: Binder tapes or binder and barrier tapes may be required to prevent extruded coverings (e.g. oversheath) from penetrating between screen wires and, particularly where followed by an HDPE sheath to achieve a reasonably smooth surface under the extruded coverings. Barrier tapes are also used to separate incompatible non-metallic materials.

2.10 OVERSHEATH

2.10.1 Material

The oversheath shall be one or more of the following materials, which shall comply with the requirements of AS/NZS 3808.

(a) PVC materials .........................................................................................V-90, 5V-90

(b) Materials for reduced fire hazard cables.....................................................HFS-90-TP

(c) Polyolefin materials .......................................................X-90, LLDPE, MDPE, HDPE

Alternatively, materials ST2 or ST7, meeting the requirements of AS/NZS 60840, may be used.

PVC materials may be used as an inner layer in composite oversheaths but are not recommended for use as the sole oversheath material.

2.10.2 Application

The oversheath (including any bonded metallic moisture barrier) shall be close fitting and be readily removable from the cable without damage to the underlying cable component. Any barrier tape or binder may however, adhere to the oversheath.

The oversheath may comprise two layers of materials from Clause 2.10.1, i.e. a composite sheath.

2.10.3 Colour

The colour of the outermost sheath shall be black unless otherwise indicated. For composite sheaths, the inner layer should be a contrasting colour.

NOTE: See Appendix A.


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2.10.4 Thickness

The nominal thickness of the oversheath or combined layer of sheath material (ts), shall be calculated from the following equation:

ts = 0.035 Dp + 1.0 mm . . .2.10.4 (1)

where

Dp = fictitious diameter under oversheath, in millimetres (derived fromAppendix B).

The calculated value of ts is then rounded off to one decimal place and is subject to a minimum value of 1.8 mm.

The minimum thickness at any point shall not fall below the nominal thickness (ts) by more than 20% of the calculated thickness (ts) plus 0.2 mm, i.e.

minimum thickness = 0.80ts 0.20 mm. . . .2.10.4 (2)

Where the oversheath is a composite sheath, the nominal thickness of the inner layer shall be between 30 % and 50 % of the total nominal thickness, but in no case shall be less than 1.0 mm. The nominal thickness of the outer layer shall be the remainder of the total nominal thickness, but in no case less than 1.0 mm.

The minimum thickness of each layer shall not fall below the calculated value given by Equation 2.10.4 (2), calculated for each layer and using the nominal thickness for that layer.

2.10.5 Tests

All tests on the oversheath shall be made as specified in Table 3.1. The category of each test shall be as specified in Table 3.1.

2.10.6 Pass criteria

The oversheath in the completed cable shall comply with the appropriate requirements specified in Table 3.1.

2.11 PROTECTION FROM INSECT ATTACK (OPTIONAL)

Some of the moisture barrier types are adequate for protection from insect attack. Where additional protection against insect attack is required, an extrusion of Polyamide 11 or 12, or two copper, brass or stainless steel tapes helically applied or other suitable means, may be incorporated in the cable construction.

NOTE: See Appendix A.

Where the means of insect protection is susceptible to damage during installation, it shall be inserted within a composite sheath or protected by a sacrificial layer or covered by other cable components.

2.12 OUTER CONDUCTIVE COATING (OPTIONAL)

To facilitate electrical testing of the integrity of the oversheath, an outer conductive coating consisting of either a coating of graphite or an extruded layer of semiconductive material may be applied.

2.13 FIBRE OPTIC COMPONENTS (OPTIONAL)

Fibre optic components may be included in the cable. Such components shall be protected from mechanical damage by placement under the metallic moisture barrier or by suitably sized screen wires or polymeric fillers laid adjacent to the fibre optic components or by other suitable means.


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2.14 CABLE IDENTIFICATION

The outermost surface of cables shall be embossed, printed or, in the case of PVC sheath, may be indented, with the manufacturers name, trade name or mark and the year of manufacture, together with the following information, as appropriate:

Cable designated voltage Legend to be marked

38/66 (72.5) kV 76/132 (145) kV 87/150 (170) kV

ELECTRIC CABLE 38/66 kV ELECTRIC CABLE 76/132 kV ELECTRIC CABLE 87/150 kV

The letters and figures shall comprise upright block characters arranged along two approximately diametrically opposite lines. The height of the characters shall be not less than 15 % of the nominal overall diameter of the cable, but in no case greater than 13 mm. The gap between the end of one set of characters and the beginning of the next shall be not greater than 500 mm.

2.15 METRE MARKING ON CABLE (OPTIONAL)

The outermost surface of the cable may be sequentially marked with numbers, in a contrasting colour, at one metre intervals. Where applied, the metre marking shall be limited to six digits and any drum length may start at any integral number.

2.16 PREPARATION FOR DELIVERY The cable shall be wound onto drums meeting the requirements of AS/NZS 2857 for timber drums or AS 3983 for metal drums, or as agreed between the supplier and purchaser.

NOTE: See also Appendices A and C.

Every drum length of cable shall have both ends of the cable sealed to prevent the ingress of water. Suitable measures shall be taken to protect cable on cable drums from damage. The end of the cable projecting from the drum barrel shall also be protected.

2.17 MARKING OF DRUMS

Every drum of cable shall be durably branded, stencilled or labelled on the outside of the flange with the following information:

(a) A manufacturers traceability number.

(b) The name or registered trade name or mark of the manufacturer or other distinguishing mark.

(c) The cable designated voltage expressed in the form U0/U.

(d) The conductor size and material.

(e) Appropriate wording to identify the insulation, moisture barrier and oversheath, and other protective coverings, if any.

(f) The gross mass of the drum and cable.

(g) An arrow to indicate the recommended direction of rotation of the drum.

(h) Where the cable is metre marked (see Clause 2.13), the start and finish numbers of metre marking.


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S E C T I O N 3 T E S T S

3.1 GENERAL

Cables shall be tested in accordance with AS/NZS 60840. Additional cable tests to be performed and pass criteria are given in Table 3.1. Some cable tests have a modified test method and criteria as indicated in Table 3.1

The tests shall be performed at ambient temperature, unless otherwise specified.

The range of approval is given in AS/NZS 60840.

The cable characteristics shall be declared as required by AS/NZS 60840.

For re-qualification test requirements for cables previously qualified, see Clause 3.7.

Type 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, design or method of manufacture, which might change the performance characteristics.

NOTE: See Appendix G for tests after installation.

3.2 SELECTION OF SAMPLES

Refer to Appendix D for the requirements for sample selection for special tests.


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TABLE 3.1

SCHEDULE OF ADDITIONAL TESTS

Test Criteria Category of test

Reference for test method

Conductor screen

(a) Thickness of extruded screen The minimum thickness at any point shall comply with the requirements of Clause 2.3.2

Routine AS/NZS 1660.2.1

1

(b) Projection of irregularities at conductor screen/insulation interface

Any projections or irregularities at the conductor screen/insulation interface, shall not protrude more than 0.075 mm into the insulation

Routine AS/NZS 1660.2.5

2 Insulation

Determination* of

(a) number of voids

(b) size of contaminants

(c) size of discoloured translucents

(d) number of contaminants

Voids 0.05 mm shall be zero Contaminants: 0.125 mm Discoloured translucents: 0.250 mm

Contaminants: 5 per 16 cm3 DRAFTING NOTE: Comment is sought on the values specified.

Sample AS/NZS 1660.2.5

Insulation screen

(a) Thickness of extruded screen As specified in Clause 2.5.2 Sample AS/NZS 1660.2.1

3

(b) Projection of irregularities at conductor screen/insulation interface

Any projections or irregularities at the conductor screen/insulation interface, shall not protrude more than 0.125 mm into the insulation

Sample AS/NZS 1660.2.5

Metallic wire screen 4

Diameter of wires Wires shall not vary from the nominal diameter by more than 5% (except for protective wires adjacent to fibre optic components)

Sample By measurement

* Measured at each end of every output length from the extrusion process. (continued)


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TABLE 3.1 (continued)

Test Criteria Category of test

Reference for test method

5 Cable

(a) Partial discharge test The magnitude of discharge shall not exceed 10 pC at the voltage specified in Table 3.2

Routine AS/NZS 1660.3

(b) Partial discharge test after bending

(i) Bending test

(ii) Partial discharge test

To be completed

The requirements as for Test 5(a) apply

Type

Type

AS/NZS 60840

AS/NZS 1660.3

(c) Spark test of oversheath (only applies to oversheath without outer conductive coating)

No breakdown of the oversheath shall occur Routine AS/NZS 1660.3, as for insulation

DRAFTING NOTE: The test method has been referenced to AS/NZS 1660.3. The current test is under review by Subcommittee EL-003-04. The test will either remain as is or IEC 62230 will be referenced.

(d) Corrosion spread test (applicable to aluminium moisture barrier not bonded to the oversheath)

As defined in IEC 60229 Type IEC 60229

TABLE 3.2

PARTIAL DISCHARGE TEST VOLTAGE LEVELS

Cable designed voltage kV

Voltage kV r.m.s.

38/66 (72.5) 76/132 (145) 87/150 (170)

57 114 131

3.3 RE-QUALIFICATION TESTS

3.3.1 Material changes

Tests in accordance with Table 3.3 shall be carried out, and results appended to the qualification test report, in order to qualify cables in which a change has been made to nominated cable components.

3.3.2 Process changes

Any change in the core manufacture process shall require Tests 1, 2, 3 of Table 3.1 and all electrical type tests as specified in AS/NZS 60840 to be repeated.

Any change in the manufacture process of other cable components shall require tests appropriate to that component as specified in AS/NZS 60840.


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TABLE 3.3

SCHEDULE FOR RE-QUALIFICATION TESTS

Component change Test

1 Core (see Note) (a) Conductor (b) Conductor screen (c) Insulation (d) Insulation screen

Nil

1(a) ) and 1(b) of Table 3.1 All appropriate sample and non-electrical type tests in AS/NZS 60840 and 2(a), (b), (c) and (d) of Table 3.1

3(a) and 3(b) of Table 3.1

2 Cable (a) Metallic wire screen (b) Metallic moisture barrier (c) Tapes (i) Binder (ii) Water-block (d) Oversheath

4 of Table 3.1

All applicable tests

Nil Test in AS/NZS 60840

All appropriate sample and non-electrical type tests in AS/NZS 60840


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APPENDIX A

PURCHASING GUIDELINES

(Informative)

A1 GENERAL

Australian/New Zealand Standards are intended to include the technical requirements for relevant products, but do not purport to comprise all the necessary provisions of a contract. This Appendix contains advice and recommendations on the information to be supplied by the purchaser at the time of enquiry or order.

A2 INFORMATION TO BE SUPPLIED BY THE PURCHASER

The purchaser should supply the following information at the time of enquiry and order, after making due reference to the explanation, advice and recommendations contained in this Appendix:

(a) The number of this Standard, i.e. AS/NZS 1429.2.

(b) Cable designated voltage.

(c) The material cross-sectional area and form of conductor and/or the required current carrying capacity.

(d) The metallic screen electrical requirements.

(e) Type of metallic moisture barrier.

(f) The make-up of the cable protective coverings, e.g. type of oversheath required.

(g) The colour of the oversheath

(h) Whether protection from insect attack is required.

(i) Whether outer conductive coating is required.

(j) Whether integrated optic fibres are required.

(k) Whether metre marking on cable is required.

(l) The cable length and individual drum lengths required.

(m) Type of drum to be used.

(n) Agreed end sealing and pulling eye requirements.


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APPENDIX B

THE FICTITIOUS CALCULATION METHOD FOR THE DETERMINATION OF THE DIMENSIONS OF INSULATION SCREEN AND PROTECTIVE

COVERINGS

(Normative)

B1 INTRODUCTION

The fictitious calculation method set out in this Appendix is used to determine dimensions of sheaths and other cable coverings. It is not a replacement for the calculation of actual diameters required for practical purposes, which should be calculated separately.

B2 GENERAL

This Appendix adopts the fictitious method of calculating thicknesses of various coverings in a cable so that any differences which can arise in independent calculations are eliminated, e.g. the assumption of conductor dimensions and the unavoidable differences between nominal and actually achieved diameters.

All thickness values and diameters shall be rounded to the first decimal place according to the rules given in Appendix E.

Binder tapes or holding strips (e.g. counter helix over metallic screen), if not thicker than 0.3 mm, are ignored in this calculation method.

B3 METHOD

B3.1 Conductors

The fictitious diameter (dL) of a conductor, calculated from the respective nominal cross-sectional area, irrespective of conductor compactness actually to be used, shall be as given in Table B1.

B3.2 Diameter over insulation

The fictitious diameter over insulation (Di) shall be as given by the following equation:

Di = dL + 2ti + 1.0 . . . B3.2

where

ti = the nominal thickness of insulation (see Table 2.2).


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TABLE B1

FICTITIOUS DIAMETER OF CONDUCTOR

Nominal cross-sectional area of conductor

mm2

Fictitious diameter (dL)

mm

95 120 150

185 240 300

400 500 630

800 1 000 1 200

1 600 2 000 2 500

11.0 12.4 13.8

15.3 17.5 19.5

22.6 25.2 28.3

31.9 35.7 39.1

45.1 50.5 56.4

B3.3 Cores

The fictitious diameter of a core (Dc) shall be as given by the following equation:

Dc = Di + 2.0 . . . B3.3

If a metallic wire screen is applied, a further addition to Dc shall be made in accordance with Paragraph B3.5.

B3.4 Metallic moisture barrier

The fictitious diameter over the metal sheath (Dm) shall be as given by the following equation:

Dm = Du + 2Tm . . . B3.4

where

Du = diameter under metal sheath

Tm = the nominal thickness of the metallic moisture barrier

B3.5 Metallic wire screen

Where a metallic wire screen is applied the increase in diameter (y) due to the metallic screen shall be as given in Table B2.


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TABLE B2

INCREASE IN FICTITIOUS DIAMETER OF A CABLE COMPONENT DUE TO METALLIC WIRE SCREEN

Gross cross-sectional area of metallic wire screen

mm2

Increase in diameter (y)

mm

50 >50 70 >70 95

>95 120 150 185

1.7 2.0 2.4

2.7 3.0 4.0

B3.6 Under non-metallic sheath

The fictitious diameter under the non-metallic sheath (Dp) shall be as given by the following equation:

Dp = Dm + y . . . B3.4


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APPENDIX C

RECOMMENDED DIAMETER OF DRUM BARREL AND INSTALLATION BENDING RADIUS FOR CABLES

(Informative)

C1 DIAMETER OF DRUM BARREL

The recommended minimum diameter of a drum barrel is determined by reference to the overall diameter of the cable multiplied by the appropriate factor specified in Table C1.

C2 INSTALLATION BENDING RADIUS

The recommended minimum installation bending radius for a cable is determined by reference to the overall diameter of the cable multiplied by the appropriate factor specified in Table C1. Where multiple cable features apply, the largest applicable multiplying factor shall be used.

TABLE C1

RECOMMENDED DIAMETER OF DRUM BARREL AND INSTALLATION BENDING RADIUS

(in multiples of cable overall diameter)

1 2 3 4

Multiplying factor

Installation bending radius Cable feature Diameter of

drum barrel During installation Installed

Lead sheath/PVC

HDPE

Polyamide with or without PVC overall

Metal tapes for termite protection

PVC/HDPE combination

18

18

25*

18

18

18

20

30*

18

20

12

15

20*

12

15

* In multiples of diameter over the polyamide layer.


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APPENDIX D

FREQUENCY OF SAMPLE TEST SELECTION AND RETEST PROCEDURE FOR SAMPLE TESTS

(Normative)

D1 FREQUENCY OF SELECTION

Frequency of selection for sample tests, except where otherwise specified in Table 3.1, shall be in accordance with Table D1.

TABLE D1

BASIS FOR NUMBER OF SAMPLES

Cable length ordered km

Number of samples

2 >2 10 >10 20 >20 30

1 2 3

4

D2 RETEST PROCEDURE

If any sample fails in any of the tests, two further samples shall be taken from the same batch and subjected to the test or tests in which the original sample failed. If both additional test samples pass the test or tests, all the drum lengths in the batch from which they were taken shall be regarded as complying with the requirements of this Standard. If either of them fail, the batch of which these samples were representative shall be regarded as failing to comply. Further re-sampling and testing shall then be a matter for negotiation.


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APPENDIX E

ROUNDING OF NUMBERS

(Normative)

E1 ROUNDING OF NUMBERS IN THE FICTITIOUS CALCULATION METHOD

The requirements given in this Paragraph apply when rounding numbers in calculating fictitious diameters and determining dimensions of component layers in accordance with Paragraph B3 of Appendix B.

When the calculated value at any stage has more than one decimal place, the value shall be rounded to one decimal place, i.e. to the nearest 0.1 mm. The fictitious diameter at each stage shall be rounded to 0.1 mm and, when used to determine the thickness or dimension of an overlying layer, it shall be rounded before being used in the appropriate equation or table. The thickness calculated from the rounded value of fictitious diameter shall in turn be rounded to 0.1 mm, as required in Paragraph B2 of Appendix B.

To illustrate these requirements, the following practical examples are given:

(a) When the figure in the second decimal place before rounding is 0, 1, 2, 3 or 4, then the figure retained in the first decimal place remains unchanged (rounding down). Examples 2.12 ~ 2.1 2.449 ~ 2.4 25.0478 ~ 25.0

(b) When the figure in the second decimal place before rounding is 9, 8, 7, 6 or 5, then the figure in the first decimal place is increased by one (rounding up). Examples 2.17 ~ 2.2 2.453 ~ 2.5 30.050 ~ 30.1

E2 ROUNDING OF NUMBERS FOR OTHER PURPOSES

For purposes other than those considered under Paragraph E1, values may have to be rounded to more than one decimal place. This may occur, for example, when calculating the average value of several measurement results, or the minimum value by applying a percentage tolerance to a given nominal value. In such cases, rounding shall be carried out to the number of decimal places specified in the relevant clauses.

The method of rounding shall then be as follows:

(a) If the last figure to be retained is followed, before rounding, by 0, 1, 2, 3 or 4, it shall remain unchanged (rounding down).

(b) If the last figure to be retained is followed, before rounding, by 9, 8, 7, 6 or 5, it shall be increased by 1 (rounding up). Examples 2.449 ~ 2.45 rounded to two decimal places 2.449 ~ 2.4 rounded to one decimal place 25.0478 ~ 25.048 rounded to three decimal places 25.0478 ~ 25.05 rounded to two decimal places 25.0478 ~ 25.0 rounded to one decimal place


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APPENDIX F

GUIDE TO THE SELECTION OF ACCESSORIES FOR HV CABLES WITH EXTRUDED INSULATION

(Informative)

DRAFTING NOTE: Comment is sought concerning the usefulness of this Appendix and whether it should be deleted. There is no referring statement to this Appendix throughout the document.

F1 GENERAL

Australian/New Zealand Standards are intended to include the technical requirements for relevant products, but do not purport to comprise all the necessary provisions of a contract. This Appendix contains advice and recommendations on the information to be supplied by the purchaser at the time of enquiry or order.

F2 INTRODUCTION

This guide excludes accessories for submarine cables and d.c. cables.

The reliability and performance of a cable circuit is dependent on the designs of the cable and accessories, the skill and experience of the person who is assembling the accessories and the use of specialized tools required for a particular accessory. It is important that controlled process measures are employed for the assembly of the accessories on site onto specially prepared cable.

It is essential to select the design of accessory to be exactly compatible with the particular cable type and the particular service application. Where a user purchases the accessories separately from the cable, then this guide will form the basis of the questions that should be asked of the manufacturers of the cable and accessories to ensure that the accessories are suitable.

F3 TERMINOLOGY

F3.1 Types of joints

F3.1.1 Straight joint

Types of straight joints are as follows:

(a) Taped joint.

(b) Prefabricated joint.

(c) Field moulded joint.

(d) Heatshrink joint.

(e) Back-to-back joint.

(f) With and without screen interruption.

F3.1.2 Transition joint

Types of transition joints are as follows:

(a) Extruded cable to mass impregnated cabled joint.

(b) Extruded cable to oil or gas filled paper cable joint.


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F3.2 Types of terminations

F3.2.1 Metal enclosed GIS terminations

Types of metal enclosed GIS terminations are as follows:

(a) Stress cone and insulator termination.

(b) Prefabricated composite dry type termination.

(c) Capacitor cone and insulator termination.

(d) Directly immersed termination.

F3.2.2 Oil immersed transformer termination

Types of oil immersed transformers terminations are as follows:

(a) Stress cone and insulator termination.

(b) Prefabricated composite dry termination.

(c) Capacitor cone and insulator termination.

(d) Directly immersed termination.

F3.2.3 Outdoor termination

Types of outdoor terminations are as follows:

(a) Prefabricated termination.

(b) Heatshrink sleeve termination.

(c) Elastomeric sleeve termination.

(d) Stress cone and insulator termination.

(e) Deflector and insulator termination.

(f) Prefabricated composite and insulator termination.

(g) Capacitor cone and insulator termination.

F3.2.4 Indoor termination

Types of indoor terminations are as follows:

(a) Prefabricated termination.

(b) Heatshrink sleeve termination.

(c) Elastomeric sleeve termination.

(d) Stress cone and insulator termination.

(e) Deflector and insulator termination.

(f) Prefabricated composite and insulator termination.

(g) Cylindrical capacitor cone and insulator termination.

(h) Torodial capacitor cone and insulator termination.

F3.2.5 Temporary termination

Types of temporary terminations are as follows:

(a) Prefabricated elastomeric sheds with stress cone termination.

(b) Heatshrink type stress control sleeve termination.

(c) Heatshrink type capacitor cone stress control cone termination.

(d) Elastomeric sleeve termination.


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F4 COMPATIBILITY (see Ref. 1)

F4.1 Accessory with the cable

F4.1.1 Cable construction

The user should determine the detailed cable construction from the cable manufacturer, which includes the information listed below as a minimum requirement. Diameters, maximum and minimum tolerances, eccentricity dimensions, construction and material need to be obtained for each of the following cable components:

(a) Number of cores.

(b) Conductor and special features (e.g. waterblocking), if any.

(c) Conductor screen.

(d) Insulation.

(e) Insulation screen.

(f) Screen wires if any.

(g) Longitudinal waterblocking, if any.

(h) Metallic barrier (e.g. extruded sheath, welded sheath or foil).

(i) Form of metallic barrier (e.g. cylindrical, corrugated or laminated).

(j) Oversheath.

(k) Terminate barrier, if any.

(l) Armour, if any.

(m) Special features (e.g. optical fibre, pilot wires, rovings).

F4.1.2 Cable operating temperature

The conductor connection should be capable of carrying the same current, and operate satisfactorily at the same operating temperatures as the cable conductor under all normal and short circuit operating conditions and also be able to withstand the cable longitudinal thermo-mechanical forces.

F4.1.3 Chemical compatibility

There can be incompatibilities between cable components, including insulants, and the materials of the accessory. For example, hydrocarbon liquids used in joints and terminations at elevated temperatures can cause swelling of XLPE insulation and reduction of the conducting properties of the screens.

The following details should be established by the user:

(a) Insulation of polymeric cable.

(b) Type of insulating liquid of lubricant used in accessories.

(c) Nature of the pressure system in paper cables (e.g. internally or externally

(d) Gas or liquid impregnant in paper cables.

(e) Type of impregnating compound in paper cables (e.g. liquid or non-draining).

F4.1.4 Cable electrical design stress

The electrical design stress of the cable must be determined. It is essential that the accessory has been designed and tested to operate at the particular cable design stress.


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F4.1.5 Mechanical and short-circuit forces in the cable

Accessories should be able to accommodate the following forces which can occur in the cable:

(a) Insulation retraction (shrink back).

(b) Insulation radial thermal expansion.

(c) Oversheath retraction (shrink back).

(d) Conductor thermomechanical thrust and retraction.

(e) Sheath thermomechanical thrust and retraction.

(f) Electromagnetic forces during short circuit.

F4.2 Accessory performance with the cable system

The accessory design should not limit the performance of the cable. The accessory must therefore match the following cable performance:

(a) Rated voltages.

(b) Current rating.

(c) Continuous, cyclic and short time overload.

(d) Short-circuit rating phase to earth and phase to phase.

(e) Basic impulse level.

(f) Specified design life.

(g) Sheath bonding design (see Ref. 2).

(h) Earth fault requirements.

F4.3 Accessory with cable system design and operating conditions

The user is advised to ensure that the accessory design is

(a) compatible with the particular cable installation design, specially mechanical loads;

(b) capable of being assembled in the site environmental conditions; and

(c) capable of a satisfactory service performance under adverse climatic conditions.

Other conditions that the user should ensure are present are as follows:

(i) Standard dimensions for terminations (e.g. height at busbar connection and at support base).

(ii) Interface design with GIS and transformer terminations.

(iii) Installation environment (e.g. tunnel, bridge, tower or shaft).

(iv) Jointing limitations (e.g. space limitations, extremes of temperature, time limitations).

(v) Type of accessory outer protection (e.g. joint box).

(vi) Special accessory protection (e.g. under water, termite infestation, bushfire).


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F5 REFERENCES

1 CIGRE 89 (1994) Accessories for HV extruded cables. Types of accessories and terminology. Glossary of names for components used in accessories for extruded cables

2 IEEE 5751988 Guide for the application of sheath-bonding methods for single-conductor cables and the calculation of induced voltages and currents in cable sheaths IEEE Product No.: WE 11379


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APPENDIX G

TESTS AFTER INSTALLATION

(Informative)

G1 SCOPE

This Appendix sets out recommendations for tests after installation. Post-installation d.c. testing of the primary insulation is not recommended. The decision to test the system after installation is not a requirement of this Standard.

G2 HIGH VOLTAGE a.c. TEST AFTER INSTALLATION

An a.c. voltage test at power frequency may be applied for 24 h with normal operating voltage of the system. Alternative higher voltage a.c. tests at lower than power frequency may be applied, as agreed between purchaser and installer.

G3 ADVICE CONCERNING TESTS AFTER INSTALLATION

If a test after installation is carried out, the following should be noted:

(a) The test is to detect defects caused during installation.

(b) After installation, the test is applied not only to the cable but also to the accessories.

G4 SHEATH INTEGRITY TEST

A sheath integrity test (e.g. 1000 V minimum insulation resistance tester) applied between the outer-most metallic layer and earth can identify post-installation damage.

*** END OF DRAFT ***

Documents

As NZS 1429.2200X Electric Cables—Polymeric Insulated for Working Voltages Above 19 - 33 (3.6) KV Up to and Including 87 - 150 (170) KV