标准编号:	GB/T 12706.1-2020
中文名称:	额定电压1 kV(Um=1.2 kV)到35 kV(Um=40.5 kV)挤包绝缘电力电缆及附件 第1部分：额定电压1 kV(Um=1.2 kV)和3 kV(Um=3.6 kV)电缆
英文名称:	Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um=1.2 kV) up to 35 kV (Um=40.5 kV)—Part 1: Cables for rated voltage of 1 kV(Um=1.2 kV)and 3 kV(Um=3.6 kV)
中标分类:	K13    电缆及其附件
行业分类:	GB    国家标准
ICS分类:	29.060.20 29.060.20    电缆 29.060.20
发布机构:	国家市场监督管理总局 国家标准化管理委员会
发布日期:	2020-03-31
实施日期:	2020-10-1
标准状态:	现行
替代旧标准:	GB/T 12706.1-2008 额定电压1kV(Um=1.2kV)到35kV(Um=40.5kV)挤包绝缘电力电缆及附件 第1部分：额定电压1kV(Um=1.2kV)和3kV(Um=3.6kV)电缆
翻译语言:	英文
文件格式:	PDF
中文字符数:	46000 字
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Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.



GB/T 12706 consists of 4 parts under the general title Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV):



——Part 1: Cables for rated voltage of 1kV (Um=1.2kV) and 3kV (Um=3.6kV);



——Part 2: Cables for rated voltages from 6kV (Um=7.2kV) up to 30kV (Um=36kV);



——Part 3: Cables for rated voltages of 35kV (Um= 40.5kV);



——Part 4: Test requirements on accessories for cables with rated voltages from 6kV (Um=7.2kV) up to 35kV (Um=40.5kV).



This is Part 1 of GB/T 12706.



This part replaces GB/T 12706.1-2008 Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV) - Part 1: Cables for rated voltage of 1kV (Um=1.2kV) and 3kV (Um=3.6kV).



In addition to editorial changes, the following main technical changes have been made with respect to GB/T 12706.1-2008:



——The requirements for inner covering materials are modified (see 7.2.2; 7.1.2 of Edition 2008);



——The requirements for extruded inner coverings are modified (see 7.2.3 and Table 9; 7.1.3 and Table 8 of Edition 2008);



——The requirements for lapped inner coverings are modified (see 7.2.4; 7.1.4 of Edition 2008);



——The requirements for overlap rate of copper strip screen are modified (see 9.2.3; 9.2.3 of Edition 2008);



——The calculation formula for nominal thickness of lead sheath are modified (see Clause 11; Clause 11 of Edition 2008);



 

——The requirements for armouring materials are modified (see 12.2; 12.2 of Edition 2008);



——The requirements for the nominal diameter of thick round metal wires and those for the nominal thickness of separation sheath or inner covering under armour are added (see 12.4, Table 10 and 12.6);



——The requirements for thickness of oversheath are modified (see 13.3; 13.3 of Edition 2008);



——The requirements for d.c. resistance of aluminium alloy conductor are added (see 15.2);



——The measurement requirements for non-metal sheath are modified (see 16.5; 16.5 of Edition 2008);



——The measurement of overlap rate and gap rate of lapped tapes is added (see 16.10 and 16.11);



——The thickness measurement of lapped inner covering and (or) lapped bedding is added (see 16.12 and 18.4);



——The measurement requirements for non-metal sheath are modified (see 18.3; 18.2 of Edition 2008);



——The requirements for pressure test at high temperature are modified (see 18.9.1; 18.7.1 of Edition 2008);



——The requirements for flame spread test on single cables are modified (see 18.16.1; 18.14.1 of Edition 2008);



——The requirements for flame spread test on bunched cables are modified (see 18.16.2; 18.14.2 of Edition 2008);



——The requirements for smoke density test are modified (see 18.16.3; 18.14.3 of Edition 2008);



——The applicable objects of the measurement of carbon black content of black PE oversheaths are modified (see 18.17.1; 18.15.1 of Edition 2008);



——The time under load of hot set test is deleted (see Tables 14 and 15; Tables 17 and 22 of Edition 2008);



 

——The calculation formula for the fictitious diameter of core of three-core cable with one conductor with reduced cross-section is added (see A.2.3);



——The rounding rules for specified values are added (see B.3);



——The measurement and calculation of overlap rate and gap rate of lapped materials are added (see Annex C);



——The requirements for delivery length and marking of finished cable are added (see E.3.2 and E.3.3);



——The recommendation of ambient temperature during installation of halogen-free flame-retardant sheathed cables is added (see E.4.1).



This part has been redrafted and modified in relation to IEC 60502-1:2004 Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 30kV (Um=36kV) - Part 1: Cables for rated voltage of 1kV (Um=1.2kV) and 3kV (Um=3.6kV). At the same time, the content of AMD 1:2009 CSV is included, and is marked with perpendicular double lines(||) in the outside page margin of the provisions concerned.



The following main structural changes have been made with respect to IEC 60502-1:2004:



——The hanging paragraphs are adjusted and 7.1, 16.6.1, 17.1, 18.1, 18.19.1 and D.2.1 are added according to the requirements of GB/T 1.1-2009, with the subsequent subclause numbers increased accordingly;



——The table numbers are adjusted in the order of references. Starting from Table 5, the correspondence between tables in this part and those in IEC 60502-1:2009 is Table 5 corresponding to Table 23, Table 6 to Table 5, Table 7 to Table 6, Table 8 to Table 7, Table 9 to Table 8, Table 10 to Table 9, Table 11 to Table 10, Table 12 to Table 11, Table 13 to Table 12, Table 14 to Table 17, Table 15 to Table 22, Table 16 to Table 13, Table 17 to Table 14, Table 18 to Table 15, Table 19 to Table 18, Table 20 to 19, Table 21 to Table 16, Table 22 to Table 20, and Table 23 to Table 21;



——11.1 and 11.12 are deleted;



——16.10, 16.11, 16.12, 18.4 and B.3 are added;



——Clause 20 is added;



——Annexes C and E are added, so that the annex numbers are changed. Annex D of this part corresponds to Annex C of IEC 60502-1:2009.



The main technical differences of this part from IEC 60502-1:2004 and their justifications are as follows:



——The adjustment on technical differences has been made on “Normative references” of this part to meet the technical specification in China; the adjustment situations are embodied in a concentrated way in Clause 2 - "Normative references" and the specific adjustments are as follows:



 IEC 60038:1983 is replaced by GB/T 156 which is modified in relation to the international standard (see 4.1);



 IEC 60811-1-1:1993 is replaced by GB/T 2951.11-2008 which is identical to the international standard (see 16.5.1, 16.8, 16.12.1, 18.2.2, 18.3.2, 18.5, 18.6, 18.21.1, and Tables 18 and 19);



 IEC 60811-1-3:1993 is replaced by GB/T 2951.13-2008 which is identical to the international standard (see 18.15, 18.18.1, 18.22.1, 18.24.1, and Tables 14, 21, 22 and 23);



 IEC 60811-2-1:1998 is replaced by GB/T 2951.21-2008 which is identical to the international standard (see 16.9.1, 18.12, 18.14.1, and Tables 14 and 15);



 IEC 60811-4-1:1985 is replaced by GB/T 2951.41-2008 which is identical to the international standard (see 18.17.1 and Table 22);



 GB/T 3048.10 is added for reference (see 12.3.3 and 13.1);



 IEC 60230:1966 is replaced by GB/T 3048.13 which is modified in relation to the international standard (see 14.3 and 17.5.1);



 IEC 60228:1978 is replaced by GB/T 3956 which is identical is the international standard (see Clause 5, 9.2.1, 15.2 and 16.4);



 GB/T 6995.3 and GB/T 6995.5 are added for reference (see E.3.3);



 IEC 60684-2:1987 is replaced by GB/T 7113.2 which is modified in relation to the international standard (see 18.16.6.1 and Table 5);



 GB/T 8170 is added for reference (see B.3);



 GB/T 11017.2-2014 is added (see 9.2.2);



 GB/T 11091 is added for reference (see 9.2.3);



 IEC 60502-2:1997 is replaced by GB/T 12706.2 which is modified in relation to the international standard (see Clause 4);



 IEC 60060-1:1989 is replaced by GB/T 16927.1 which is modified in relation to the international standard (see 14.3);



 IEC 60754-1:1994 is replaced by GB/T 17650.1 which is identical to the international standard (see Table 5 and 18.16.4);



 IEC 60754-2:1991 is replaced by GB/T 17650.2 which is identical to the international standard (see Table 5 and 18.16.5);



 IEC 60332-1:1993 is replaced by GB/T 18380.11, GB/T 18380.12 and GB/T 18380.13 which are identical to the international standard (see 18.16.1);



 GB/T 18380.33, GB/T 18380.34 and GB/T 18380.36 are added for reference (see 18.16.2);



 GB/T 19666 is added for reference (see E.1.3);



 JB/T 8137 (all parts) is added for reference (see E.3.4.1);



 IEC 60183:1984 is replaced by JB/T 8996 which is not equivalent to the international standard (see 4.1);



 The non-normative reference IEC 60724 is included in the Bibliography;



 IEC 61034-2:1997 and ISO 48:1994 are changed to undated references.



——In order to meet the technical requirements of China, the term and definition of “fictitious value” are deleted (see Clause 3);



——In order to meet the technical requirements of China, the thickness requirements (see 7.2.3 and 7.2.4) and technical requirements (see 12.7, 16.5 and 18.3) for extruded and lapped inner coverings are modified;



——The thickness requirements for other metal sheaths are deleted (see Clause 11);



——In order to meet the technical requirements of China, the measurement of overlap rate (see 16.10) and that of gap rate (see 16.11) of lapped materials are added;



——In order to meet the technical requirements of China, the measurement of total thickness of lapped inner covering and (or) lapped bedding (see 16.12) and their technical requirements (see 18.4) are added;



——In order to clarify the requirements of copper strip materials for cables, the requirements of copper raw materials are added (see 9.2.3);



——To ensure the quality of extruded separation sheath and oversheath, the requirements for spark test of extruded separation sheath (see 12.3.3) and those for spark test of oversheath (see 13.1) are added;



——In order to meet the technical requirements of China, the requirements for the diameter of thick round metal wire and those for the thickness of separation sheath or inner covering under armour are added (see 12.4, Table 10 and 12.6);



——In order to meet the technical requirements of China, the d.c. resistance requirements of aluminium alloy conductors are added (see 15.2);



——In order to meet the technical requirements of China, the application scope and requirements of fire tests (see 18.16.1 and 18.16.2) and the applicable objects of carbon black test (see 18.17.1) are modified;



——In order to improve the domestic technical requirements for power cables, supplementary items for cable products are added (see Clause 20 and Annex E);



——The calculation formulae for the fictitious diameter of core of three-core cables with one conductor with reduced cross-section, five-core cables with one conductor with reduced cross-section, and five-core cables with two conductors with reduced cross-section are added (see A.2.3); the rounding rules of specified values are added (see B.3) to meet the technical requirements of China;



——In order to define the overlap rate and gap rate, the measurement and calculation of overlap rate and gap rate of lapped materials are added (see Annex C).



The following editorial changes have been made in this part:



——In order to adapt to China's technical standard system, the standard name is changed to Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV) - Part 1: Cables for rated voltage of 1kV (Um=1.2kV) and 3kV (Um=3.6kV);



——The “Bibliography” is added.



This part was proposed by the China Electrical Equipment Industrial Association.



This part is under the jurisdiction of SAC/TC 213 National Technical Committee on Wires and Cables of Standardization Administration of China.



The previous editions of this part are as follows:



——GB 12706.1-1991, GB/T 12706.1-2002 and GB/T 12706.1-2008;



——GB 12706.2-1991 and GB 12706.3-1991.





Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV) -

Part 1: Cables for rated voltage of 1kV (Um=1.2kV) and 3kV (Um=3.6kV)



1 Scope



This part of GB/T 12706 specifies the construction, dimensions and test requirements of power cables with extruded insulation for rated voltages of 1kV (Um=1.2kV) and 3kV (Um=3.6kV).



This part is applicable to the power cables with extruded insulation for rated voltages of 1kV (Um=1.2kV) and 3kV (Um=3.6kV) for fixed installations such as distribution networks or industrial installations.



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.



GB/T 156 Standard voltages (GB/T 156-2017, IEC 60038:2009, MOD)

GB/T 2951.11-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 11: Methods for general application - Measurement of thickness and overall dimensions - Tests for determining the mechanical properties (IEC 60811-1-1:2001, IDT)

GB/T 2951.12-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 12: Methods for general application - Thermal ageing methods (IEC 60811-1-2:1985, IDT)

GB/T 2951.13-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 13: Methods for general application - Measurement for determining the density - Water absorption tests - Shrinkage test (IEC 60811-1-3:2001, IDT)

GB/T 2951.14-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 14: Methods for general application - Test at low temperature (IEC 60811-1-4:1985, IDT)

GB/T 2951.21-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 21: Methods specific to elastomeric compounds - Ozone resistance, hot set and mineral oil immersion tests (IEC 60811-2-1:2001, IDT)

GB/T 2951.31-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 31: Methods specific to PVC compounds - Pressure test at high temperature - Test for resistance to cracking (IEC 60811-3-1:1985, IDT)

GB/T 2951.32-2008 Common test methods for insulating and sheathing materials of electric cables - Part 32: Methods specific to PVC compounds - Loss of mass test - Thermal stability test (IEC 60811-3-2:1985, IDT)

GB/T 2951.41-2008 Common test methods for insulating and sheathing materials of electric and optical cables - Part 41: Methods specific to polyethylene and polypropylene compounds - Resistance to environmental stress cracking - Measurement of the melt flow index - Carbon black and/or mineral filler content measurement in polyethylene by direct combustion - Measurement of carbon black content by thermo gravimetric analysis (TGA) - Assessment of carbon black dispersion in polyethylene using a microscope (IEC 60811-4-1:2004, IDT)

GB/T 3048.10 Test methods for electrical properties of electric cables and wires - Part 10: Spark test of extruded protective sheaths

GB/T 3048.13 Test methods for electrical properties of electric cables and wires - Part 13: Impulse voltage test (GB/T 3048.13-2007, IEC 60230:1966, IEC 60060-1:1989, MOD)

GB/T 3956 Conductors of insulated cables (GB/T 3956-2008, IEC 60228:2004, IDT)

GB/T 6995.3 Markings for electric cables and wires - Part 3: Identifications of cables and wires

GB/T 6995.5 Markings for electric wires and cables - Part 5: Identifications of insulated cores of power cables

GB/T 7113.2 Flexible insulating sleeving - Part 2: Methods of test (GB/T 7113.2-2014, IEC 60684-2:2003, MOD)

GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values

GB/T 11017.2-2014 Power cables with cross-linked polyethylene insulation and their accessories for rated voltage of 110kV (Um=126kV) - Part 2: Power cables

GB/T 11091 Copper strip for cables

GB/T 12706.2 Power cables with extruded insulation and their accessories for rated voltages from 1kV (Um=1.2kV) up to 35kV (Um=40.5kV) - Part 2: Cables for rated voltages from 6kV (Um=7.2kV) up to 30kV (Um=36kV) (GB/T 12706.2-2020, IEC 60502-2:2014, MOD)

GB/T 16927.1 High-voltage test techniques - Part 1: General definitions and test requirements (GB/T 16927.1-2011, IEC 60060-1:2010, MOD)

GB/T 17650.1 Test on gases evolved during combustion of materials from cables - Part 1: Determination of the amount of halogen acid gas (GB/T 17650.1-1998, IEC 60754-1:1994, IDT)

GB/T 17650.2 Test on gases evolved during combustion of materials from cables - Part 2: Determination of degree of acidity of gases by measuring pH and conductivity (GB/T 17650.2-1998, IEC 60754-2:1991, IDT)

GB/T 18380.11 Tests on electric and optical fibre cables under fire conditions - Part 11: Test for vertical flame propagation for a single insulated wire or cable - Apparatus (GB/T 18380.11-2008, IEC 60332-1-1:2004, IDT)

GB/T 18380.12 Tests on electric and optical fibre cables under fire conditions - Part 12: Test for vertical flame propagation for a single insulated wire or cable - Procedure for 1kW pre-mixed flame (GB/T 18380.12-2008, IEC 60332-1-2:2004, IDT)

GB/T 18380.13 Tests on electric and optical fibre cables under fire conditions - Part 13: Test for vertical flame propagation for a single insulated wire or cable - Procedure for determination of flaming droplets/particles (GB/T 18380.13-2008, IEC 60332-1-3:2004, IDT)

GB/T 18380.33 Tests on electric and optical fibre cables under fire conditions - Part 33: Test for vertical flame spread of vertically-mounted bunched wires or cables - Category A (GB/T 18380.33-2008, IEC 60332-3-22:2000, IDT)

GB/T 18380.34 Tests on electric and optical fibre cables under fire conditions - Part 34: Test for vertical flame spread of vertically-mounted bunched wires or cables - Category B (GB/T 18380.34-2008, IEC 60332-3-23:2000, IDT)

GB/T 18380.35 Tests on electric and optical fibre cables under fire conditions - Part 35: Test for vertical flame spread of vertically-mounted bunched wires or cables - Category C (GB/T 18380.35-2008, IEC 60332-3-24:2000, IDT)

GB/T 18380.36 Tests on electric and optical fibre cables under fire conditions - Part 36: Test for vertical flame spread of vertically-mounted bunched wires or cables - Category D (GB/T 18380.36-2008, IEC 60332-3-25:2000, IDT)

GB/T 19666 Flame retardant and fire resistant wires and cables

JB/T 8137 (all parts) Delivery drums for wires and cables

JB/T 8996 Guide to the selection of high-voltage cables (JB/T 8996-2014, IEC 60183:1984, NEQ)

ISO 48 Rubber, vulcanized or thermoplastic - Determination of hardness (hardness between 10 IRHD and 100 IRHD)

IEC 61034-2 Measurement of smoke density of cables burning under defined conditions - Part 2: Test procedure and requirements



3 Terms and definitions



For the purposes of this document, the following terms and definitions apply.



3.1 Terms concerning dimensional values



3.1.1

nominal value

value by which a quantity is designated and which is often used in tables



Note: Usually, in this part, 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



Note: It is used, for example, for the calculation of other dimensional values.



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



3.2 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 part, 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 U0/U(Um) of the cables considered in this part are 0.6//1(1.2)kV and 1.8/3(3.6)kV.



Note: The voltages given above are the correct designations although in some countries other designations are used, e.g. 1.7/3kV or 1.9/3.3kV instead of 1.8/3kV.



In the voltage designation of cables U0/U(Um):



——U0 is the rated power frequency voltage between conductor and earth or metal 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 value of the "highest system voltage'' for which the equipment may be used (see GB/T 156).



The rated voltage of the cable 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:



——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 1min;

Foreword III
1 Scope
2 Normative references
3 Terms and definitions
4 Voltage designations and materials
5 Conductors
6 Insulation
7 Assembly of multicore cables, inner coverings and fillers
8 Metal layers for single-core and multicore cables
9 Metal screen
10 Concentric conductor
11 Lead sheath
13 Oversheath
14 Test conditions
15 Routine tests
16 Sample tests
17 Electrical type tests
18 Non-electrical type tests
19 Electrical tests after installation
20 Supplementary terms for cable products
Table 17 Non-electrical type tests
Annex A (Normative) Fictitious calculation method for determination of dimensions of protective coverings
Annex B (Normative) Rounding of numbers
Annex C (Normative) Measurement and calculation of lapped overlap rate and gap rate
Annex D (Normative) Determination of hardness of HEPR insulations
Annex E (Normative) Supplementary terms of cable products
Bibliography
Figure D.1 Test on surfaces of large radius of curvature
Figure D.2 Test on surfaces of small radius of curvature
Figure E.1 Composition and arrangement sequence of product model
Table 1 Rated voltages U
Table 2 Insulating compounds
Table 3 Maximum conductor temperatures for different types of insulating compound
Table 4 Maximum conductor temperatures for different types of sheathing compound
Table 5 Test method and requirements of halogen free compounds
Table 6 Nominal thickness of PVC/A insulation
Table 7 Nominal thickness of cross-linked polyethylene (XLPE) insulation
Table 8 Nominal thickness of ethylene propylene rubber (EPR) and hard ethylene propylene rubber (HEPR) insulation
Table 9 Thickness of extruded inner covering
Table 10 Nominal diameter of round armour wires
Table 11 Nominal thickness of armour tapes
Table 12 Routine test voltages
Table 13 Number of samples for sample tests
Table 14 Test requirements for particular characteristics of various thermosetting insulating compounds
Table 15 Test requirements for particular characteristics of elastomeric sheathing compound
Table 16 Electrical type test requirements for insulating compounds
Table 17 Non-electrical type tests
Table 18 Test requirements for mechanical characteristics of cable insulation (before and after ageing)
Table 19 Test requirements for mechanical characteristics of sheathing compounds (before and after ageing)
Table 20 Test requirements for particular characteristics for PVC sheathing compounds
Table 21 Test requirements for particular characteristics for PVC insulating compound
Table 22 Test requirements for particular characteristics of PE (thermoplastic polyethylene) sheathing compounds
Table 23 Test requirements for particular characteristics for halogen free sheathing compounds
Table A.1 Fictitious diameter of conductor
Table A.2 Assembly coefficient K for laid-up cores
Table A.3 Increase of diameter for concentric conductors and metal screens
Table A.4 Increase of diameter for additional bedding
Table B.1 Rounded digits of specified values, measured values or their calculated value
Table E.1 Cable models
Table E.2 Recommended nominal cross-sectional area of conductor of neutral wire and protective wire of multi-core cable
Table E.3 Minimum bending radius during cable installation

额定电压1 kV(Um=1.2 kV)到35 kV (Um=40.5 kV)挤包绝缘电力电缆及附件 第1部分：额定电压1 kV(Um=1.2 kV)和3 kV(Um=3.6 kV)电缆

1 范围
GB/T 12706的本部分规定了额定电压1 kV(Um=1.2 kV)和3 kV(Um=3.6 kV)挤包绝缘电力电缆的结构、尺寸和试验要求。
本部分适用于配电网或工业装置中额定电压1 kV(Um=1.2 kV)和3 kV(Um=3.6 kV)固定安装的挤包绝缘电力电缆。
本部分不适用于特殊安装和运行条件的电缆，例如架空线路、采矿工业、核电厂(安全壳内及其附近)以及水下或船舶的电缆。
2规范性引用文件
下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件，仅注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本(包括所有的修改单)适用于本文件。
GB/T 156 标准电压(GB/T 156—2017，IEC 60038：2009，MOD)
GB/T 2951.11—2008 电缆和光缆绝缘和护套材料通用试验方法 第11部分：通用试验方法——厚度和外形尺寸测量——机械性能试验(IEC 60811-1-1：2001，IDT)
GB/T 2951.12—2008 电缆和光缆绝缘和护套材料通用试验方法 第12部分：通用试验方法——热老化试验方法(IEC 60811-1-2：1985，IDT)
GB/T 2951.13—2008 电缆和光缆绝缘和护套材料通用试验方法 第13部分：通用试验方法——密度测定方法——吸水试验——收缩试验(IEC 60811-1-3：2001，IDT)
GB/T 2951.14—2008 电缆和光缆绝缘和护套材料通用试验方法 第14部分：通用试验方法——低温试验(IEC 60811-1-4：1985，IDT)
GB/T 2951.21—2008 电缆和光缆绝缘和护套材料通用试验方法 第21部分：弹性体混合料专用试验方法——耐臭氧试验——热延伸试验——浸矿物油试验(IEC 60811-2-1：2001，IDT)
GB/T 2951.31—2008 电缆和光缆绝缘和护套材料通用试验方法 第31部分：聚氯乙烯混合料专用试验方法——高温压力试验——抗开裂试验(IEC 60811-3-1：1985，IDT)
GB/T 2951.32—2008 电缆和光缆绝缘和护套材料通用试验方法 第32部分：聚氯乙烯混合料专用试验方法——失重试验——热稳定性试验(IEC 60811-3-2：1985，IDT)
GB/T 2951.41—2008 电缆和光缆绝缘和护套材料通用试验方法 第41部分：聚乙烯和聚丙烯混合料专用试验方法——耐环境应力开裂试验——熔体指数测量方法——直接燃烧法测量聚乙烯中碳黑和(或)矿物质填料含量——热重分析法(TGA)测量碳黑含量——显微镜法评估聚乙烯中碳黑分散度(IEC 60811-4-1：2004，IDT)
GB/T 3048.10 电线电缆电性能试验方法 第10部分：挤出护套火花试验
GB/T 3048.13 电线电缆电性能试验方法 第13部分：冲击电压试验(GB/T 3048.13—2007，IEC 60230：1966，IEC 60060-1：1989，MOD)
GB/T 3956 电缆的导体 (GB/T 3956—2008，IEC 60228：2004，IDT)
GB/T 6995.3 电线电缆识别标志方法 第3部分：电线电缆识别标志
GB/T 6995.5 电线电缆识别标志方法 第5部分：电力电缆绝缘线芯识别标志
GB/T 7113.2绝缘软管 第2部分：试验方法(GB/T 7113.2—2014，IEC 60684-2：2003，MOD)
GB/T 8170 数值修约规则与极限数值的表示和判定
GB/T 11017.2—2014 额定电压110 kV(Um-126 kV)交联聚乙烯绝缘电力电缆及其附件 第2部分：电缆
GB/T 11091 电缆用铜带
GB/T 12706.2 额定电压1 kV(Um=1.2 kV)到35 kV(Um=40.5 kV)挤包绝缘电力电缆及附件 第2部分：额定电压6 kV(Um=7.2 kV)到30 kV(Um=36 kV)电缆(GB/T 12706.2—2020，IEC 60502-2：2014，MOD)
GB/T 16927.1 高电压试验技术 第1部分：一般定义及试验要求(GB/T 16927.1—2011，IEC 60060-1：2010，MOD)
GB/T 17650.1取自电缆或光缆的材料燃烧时释出气体的试验方法 第1部分：卤酸气体总量的测定(GB/T 17650.1—1998，IEC 60754-1：1994，IDT)
GB/T 17650.2 取自电缆或光缆的材料燃烧时释出气体的试验方法 第2部分：用测量pH值和电导率来测定气体的酸度(GB/T 17650.2—1998，IEC 60754-2：1991，IDT)
GB/T 18380.11 电缆和光缆在火焰条件下的燃烧试验 第11部分：单根绝缘电线电缆火焰垂直蔓延试验 试验装置(GB/T 18380.11—2008，IEC 60332-1-1：2004，IDT)
GB/T 18380.12 电缆和光缆在火焰条件下的燃烧试验 第12部分：单根绝缘电线电缆火焰垂直蔓延试验1 kW预混合型火焰试验方法(GB/T 18380.12—2008，IEC 60332-1-2：2004，IDT)
GB/T 18380.13 电缆和光缆在火焰条件下的燃烧试验 第13部分：单根绝缘电线电缆火焰垂直蔓延试验 测定燃烧的滴落(物)/微粒的试验方法(GB/T 18380.13—2008，IEC 60332-1-3：2004，IDT)
GB/T 18380.33 电缆和光缆在火焰条件下的燃烧试验 第33部分：垂直安装的成束电线电缆火焰垂直蔓延试验 A类(GB/T 18380.33—2008，IEC 60332-3-22：2000，IDT)
GB/T 18380.34电缆和光缆在火焰条件下的燃烧试验 第34部分：垂直安装的成束电线电缆火焰垂直蔓延试验 B类(GB/T 18380.34—2008，IEC 60332-3-23：2000，IDT)
GB/T 18380.35 电缆和光缆在火焰条件下的燃烧试验 第35部分：垂直安装的成束电线电缆火焰垂直蔓延试验 C类(GB/T 18380.35—2008，IEC 60332-3-24：2000，IDT)
GB/T 18380.36 电缆和光缆在火焰条件下的燃烧试验 第36部分：垂直安装的成束电线电缆火焰垂直蔓延试验 D类(GB/T 18380.36—2008，IEC 60332-3-25：2000，IDT)
GB/T 19666 阻燃和耐火电线电缆通则
JB/T 8137(所有部分)电线电缆交货盘
JB/T 8996 高压电缆选择导则(JB/T 8996—2014，IEC 60183：1984，NEQ)
ISO 48硫化型或热塑型橡胶 硬度确定(硬度在10 IRHD和100 IRHD之间)[Rubber，vulcanized or thermoplastic—Determination of hardness(hardness between 10 IRHD and 100 IRHD)]
IEC 61034-2电缆或光缆在特定条件下燃烧的烟密度测定 第2部分：试验步骤和要求(Measurement of smoke density of cables burning under defined conditions—Part 2：Test procedure and requirements)
3术语和定义
下列术语和定义适用于本文件。
3.1 有关尺寸值的术语
3.1.1
标称值 nominal value
指定的量值并经常用于表格之中。
注：在本部分中，通常标称值引伸出的量值在考虑规定公差下通过测量进行检验。
3.1.2
近似值approximate value
既不保证也不检查的数值。
注：近似值可用于其他尺寸值的计算。
3.1.3
中间值 median value
将试验得到的若干数值以递增(或递减)的次序依次排列时，若数值的数目是奇数，中间的那个值；若数值的数目是偶数，中间两个数值的平均值。
3.2有关试验的术语
3.2.1
例行试验 routine tests
由制造方在成品电缆的所有制造长度上进行的试验，以检验所有电缆是否符合规定的要求。
3.2.2
抽样试验sample tests
由制造方按规定的频度，在成品电缆试样上或在取自成品电缆的某些部件上进行的试验，以检验电缆是否符合规定要求。
3.2.3
型式试验type tests
按一般商业原则对本部分所包含的一种类型电缆在供货之前所进行的试验，以证明电缆具有满足预期使用条件的满意性能。
注：该试验的特点为除非电缆材料或设计或制造工艺的改变可能改变电缆的特性，试验做过以后就不需要重做。
3.2.4
安装后电气试验electrical tests after installation
在安装后进行的试验，用以证明安装后的电缆及其附件完好。
4 电压标示和材料
4.1 额定电压
本部分中电缆的额定电压U0/U(Um)为0.6//1(1.2)kV和1.8/3(3.6)kV。
注：上述电压的表示方法是合适的，尽管在一些国家采用其他的表示方法.例如：1.7/3 kV或1.9/3.3 kV代替1.8/3 kV。
在电缆的电压表示U0/U(Um)中：
——U0：电缆设计用导体对地或金属屏蔽之间的额定工频电压；
——U：电缆设计用导体间的额定工频电压；
——Um：设备可承受的“最高系统电压”的最大值(见GB/T 156)。
电缆的额定电压应适合电缆所在系统的运行条件。为了便于选择电缆，将系统划分为下列三类：
——A类：该类系统任一相导体与地或接地导体接触时，能在1 min内与系统分离；
——B类：该类系统可在单相接地故障时作短时运行，接地故障时间按JB/T 8996不应超过1 h；对于本部分包括的电缆，在任何情况下允许不超过8 h更长的带故障运行时间。任何一年接地故障的总持续时间不应超过125 h；
——C类：包括不属于A类、B类的所有系统。
注：宜认识到，在系统接地故障不能立即自动解除时，故障期间加在电缆绝缘上过高的电场强度，会在一定程度上缩短电缆寿命。如预期系统会经常地运行在持久的接地故障状态下，该系统可划为C类。
用于三相系统的电缆，U0的推荐值见表1。
表1 额定电压U0
系统最高电压Um
kV 额定电压U0
kV
A类B类 C类
1.2
3.6 0.6
1.8 0.6
3.6a
a这一类包括在GB/T 12706.2的3.6/6(7.2)kV电缆中。

4.2绝缘混合料
绝缘混合料及其代号见表2。
表2绝缘混合料
绝缘混合料 代号
热塑性
用于额定电压U0/U≤1.8/3 kV电缆的聚氯乙烯
热固性
乙丙橡胶或类似绝缘混合料(EPR或EPDM)
高弹性模数或高硬度乙丙橡胶
交联聚乙烯
PVC/Aa

EPR
HEPR
XLPE
a 聚氯乙烯为基料的绝缘混合料用于额定电压U0/U=3.6/6 kV电缆时，在GB/T 12706.2中表示为PVC/B。

各种绝缘混合料电缆的导体最高温度见表3。
表3 各种绝缘混合料电缆的导体最高温度
绝缘混合料 导体最高温度
正常运行 短路(最长持续5 s)
聚氯乙烯(PVC/A)
导体截面积≤300 mm2
导体截面积>300 mm2
交联聚乙烯(XLPE)
乙丙橡胶(EPR和HEPR)
70
70
90
90
160
140
250
250

表3中的温度由绝缘材料固有特性决定，使用这些数据计算额定电流时还应考虑其他因素。
例如在正常运行条件下，如电缆直接埋入地下，按表3中所规定的导体最高温度作连续负荷(100％负荷因数)运行，电缆周围土壤的热阻系数经过一定时间后，会因干燥而超过原始值，因此导体温度可能超过最高温度。如果能预料这类运行条件，应采取适当的预防措施。
短路温度的导则可参照IEC 60724。
4.3护套混合料
不同类型护套混合料电缆的导体最高温度见表4。
表4 不同类型护套混合料电缆的导体最高温度
护套混合料 代号 正常运行导体最高温度
℃
热塑性
聚氯乙烯(PVC)

聚乙烯

无卤阻燃
弹性体
氯丁橡胶、氯磺化聚乙烯或类似聚合物
ST1
ST2
ST3
ST7
ST8

SE1
80
90
80
90
90

85

5 导体
导体应是符合GB/T 3956的第1种或第2种或第5种镀金属层或不镀金属层退火铜导体、第1种或第2种铝或铝合金导体。
6 绝缘
6.1 材料
绝缘应为表2所列的一种挤包成型材料。
无卤电缆的绝缘应符合表5规定。
表5 无卤混合料的试验方法和要求
试验项目 单位 要求
酸气含量试验(GB/T 17650.1)
溴和氯含量(以HCl表示)，最大值
％
0.5
氟含量试验(GB/T 7113.2)
氟含量，最大值
％
0.1
PH值和电导率试验(GB/T 17650.2)
pH值，最小值
电导率，最大值

μS/mm
4.3
10

6.2 绝缘厚度
绝缘标称厚度见表6、表7和表8。任何隔离层的厚度不应包括在绝缘厚度之中。
表6聚氯乙烯(PVC/A)绝缘标称厚度
导体标称截面积
mm 额定电压U0/U(Um)下的绝缘标称厚度
mm
0.6/1(1.2)kV 1.8/3(3.6)kV
1.5,2.5
4,6
10,16
25,35
50,70
95,120
150
185
240
300
400
500～800
1 000 0.8
1.0
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0

2.2
2.2
2.2
2.2
2.2
2.2
2.2
2.4
2.6
2.8
3.0
注：不宜采用任何小于以上给出的导体截面。

表7 交联聚乙烯(XLPE)绝缘标称厚度
导体标称截面积
mm2 额定电压U0/U(Um)下的绝缘标称厚度
mm
0.6/1(1.2)kV 1.8/3(3.6)kV
1.5,2.5
4,6
10,16
25,35
50
70,95
120
150
185
240
300
400
500
630
800
1 000 0.7
0.7
0.7
0.9
1.0
1.1
1.2
1.4
1.6
1.7
1.8
2.0
2.2
2.4
2.6
2.8 —
—
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.2
2.4
2.6
2.8
注：不宜采用任何小于以上给出的导体截面。

表8 乙丙橡胶(EPR)和硬乙丙橡胶(HEPR)绝缘标称厚度
导体标称截面积
mm2 额定电压U0/U(Um)下的绝缘标称厚度
mm
0.6/1(1.2)kV 1.8/3(3.6)kV
EPR HEPR EPR HEPR
1.5,2.5
4.6
10,16
25,35
50
70
95
120
150
185
240
300
400
500
630
800
1 000 1.0
1.0
1.0
1.2
1.4
1.4
1.6
1.6
1.8
2.0
2.2
2.4
2.6
2.8
2.8
2.8
3.0 0.7
0.7
0.7
0.9
1.0
1.1
1.1
1.2
1.4
1.6
1.7
1.8
2.0
2.2
2.4
2.6
2.8 —
—
2.2
2.2
2.2
2.2
2.4
2.4
2.4
2.4
2.4
2.4
2.6
2.8
2.8
2.8
3.0 —
—
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.2
2.4
2.6
2.8
注：不宜采用任何小于以上给出的导体截面。

7 多芯电缆的缆芯、内衬层和填充物
7.1 概述
多芯电缆的缆芯与电缆的额定电压及每根绝缘线芯上有否金属屏蔽层有关。
7.2～7.4不适用于有护套单芯电缆成缆的缆芯。
7.2 内衬层与填充
7.2.1 结构
内衬层可挤包或绕包。
除五芯以上电缆外，圆形绝缘线芯电缆只有在绝缘线芯间的间隙被填充时才可采用绕包内衬层。
挤包内衬层前允许用合适的带子扎紧。
7.2.2 材料
用于内衬层和填充物的材料应适合电缆的运行温度并与电缆绝缘材料相兼容。除纵向阻水型电缆外，内衬层和填充物应采用非吸湿材料。
无卤电缆的内衬层和填充应符合表5规定。
7.2.3挤包内衬层
挤包内衬层的标称厚度见表9。
表9挤包内衬层厚度
缆芯假设直径
mm 挤包内衬层标称厚度
mm

>25.0
>35.0
>45.0
>60.0
>80.0 ≤25.0
≤35.0
≤45.0
≤60.0
≤80.0
— 1.0
1.2
1.4
1.6
1.8
2.0

7.2.4绕包内衬层
缆芯假设直径为40.0 mm及以下时，绕包内衬层的标称厚度取0.4 mm；如大于40.0 mm时，则取0.6 mm。
绕包内衬层采用单根或多根带材重叠绕包而成。当多根带材绕包时，每一根均应重叠绕包。
7.3额定电压0.6/1 kV电缆
7.3.1 一般规定
额定电压0.6/1 kV电缆可在绝缘线芯或缆芯外包覆统包金属层。
注：电缆采用金属层与否，取决于有关规范和安装要求，以免可能遭受机械损伤或直接电接触的危险。
7.3.2 有统包金属层的电缆(见第8章)
电缆缆芯外应有内衬层，内衬层和填充应符合7.2规定，并应为非吸湿性材料。
如果所用金属带的单层厚度不超过0.3 mm，金属带也可直接绕包在缆芯外，省略内衬层，这种电缆应符合18.19规定的特殊弯曲试验要求。
7.3.3 无统包金属层的电缆(见第8章)
只要电缆外部形状保持圆整而且缆芯和护套之间不粘连，内衬层就可省略。
热塑性护套包覆在10 mm2及以下圆形缆芯的情况下，外护套可嵌入缆芯间隙。
如果采用内衬层，那么其厚度不必符合7.2.3或7.2.4规定。
7.4额定电压1.8/3 kV电缆
7.4.1 一般规定
额定电压1.8/3 kV电缆应具有分相或统包金属层。
7.4.2有统包金属层的电缆(见第8章)
缆芯外应有内衬层，内衬层和填充物应符合7.2规定，并应为非吸湿性材料。
7.4.3 有分相金属层的电缆(见第9章)
各绝缘线芯的金属层应相互接触。
有附加统包金属层(见第8章)的电缆，当金属材料与分相包覆的金属层材料相同时，缆芯外应有内衬层。内衬层与填充物应符合7.2规定，并应为非吸湿件材料。
当分相与统包金属层采用的金属材料不同时，应采用符合13.2中规定的任一种材料挤包隔离套将其隔开。对于铅套电缆，铅套与分相包覆的金属层之间的隔离，可采用符合7.2规定的内衬层。
既无铠装又无同心导体，也无其他统包金属层(见第8章)的电缆，只要电缆外形保持圆整，可省略内衬层。如采用热塑性护套包覆10 mm2及以下的圆形缆芯时，外护套可嵌入缆芯间隙。若采用内衬层，其厚度不必按7.2.3或7.2.4规定。
8 单芯或多芯电缆的金属层
本部分包括以下类型的金属层：
a)金属屏蔽(见第9章)；
b)同心导体(见第10章)；
c)铅套(见第11章)；
d)金属铠装(见第12章)。
金属层应由上述的一种或几种型式组成，包覆在多芯电缆的单独绝缘线芯上或单芯电缆上时应是非磁性的。
9 金属屏蔽
9.1 结构
金属屏蔽应由一根或多根金属带、金属编织、金属丝的同心层或金属丝与金属带的组合结构组成。
金属屏蔽也可是金属套或符合9.2规定的金属铠装层。
选择金属屏蔽材料时，应特别考虑存在腐蚀的可能性，这不仅为了机械安全，也为了电气安全。