Power cables with cross-linked polyethylene insulation and their accessories for rated voltage of 110 kV(Um=126 kV)―Part 1:Test methods and requirements
1 Scope
This part of GB/T 11017 specifies the test methods and requirements of power cable systems, with cross-linked polyethylene insulation, cables alone and their accessories for rated voltage of 110 kV (Um =126 kV).
This Part is applicable to single-core cables and their accessories for usual conditions of installation and operation, but not to special cables and their accessories, such as submarine cables, for which modifications to the standard tests may be necessary or special test conditions may need to be devised.
This Part does not cover transition joints between cables with cross-linked polyethylene insulation and paper insulated cables.
2 Normative References
The following referenced documents are indispensable for the application of this standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
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 60811-1-2:2000, 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)
Electromagnetic compatibility — Testing and measurement techniques — Surge immunity test
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 and optical 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 3048.12 Test methods for electrical properties of electric cables and wires — Part 12: Partial discharge test (GB/T 3048.12-2007, IEC 60885-3:1988, MOD)
GB/T 3048.13 Test methods for electrical properties of electric cables and wires — Part 13: Impulse voltage test (IEC 3048.13-2007, IEC 60060-1:1989, MOD)
GB/T 3956 Conductors of insulated cables (GB/T 3956-2008, IEC 60228:2004, IDT)
GB/T 16927.1 High-voltage Test Techniques — Part 1: General Definitions and Test Requirements (GB/T 16927.1-2011, IEC 60060-1:2006, MOD)
GB/T 18380.12 Test 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)
JB/T 10696.5-2007 Test methods for determining mechanical physical and chemical properties of electric cables and wires — Part 5: Corrosion spread test
JB/T 10696.6-2007 Test methods for determining mechanical physical and chemical properties of electric cables and wires — Part 6: Test for abrasion of oversheaths
IEC 60183 Guide to the selection of high-voltage cables
IEC 60229:2007 Electric cables — Tests on extruded oversheaths with a special protective function
IEC 60287-1-1:2006 Electric cables — Calculation of the current rating — Part 1-1: Current rating equations (100% load factor) and calculation of losses — General
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1 Definitions of dimensional values (thicknesses, cross-sections, etc.)
3.1.1
nominal value
value by which a quantity is designated and which is often used in tables
Note to entry: Usually, in this Part, nominal values give rise to values to be checked by measurements taking into account specified tolerances.
3.1.2
median value
when several test results have been obtained and ordered in an increasing (or decreasing) succession, middle value if the number of available values is odd, and mean of the two middle values if the number is even
3.2 Definitions concerning tests
3.2.1
routine test
tests made by the manufacturer on each manufactured component (length of cable or accessory) to check that the component meets the specified requirements
3.2.2
sample test
tests made by the manufacturer on samples of completed cable or components taken from a completed cable or accessory, at a specified frequency as to verify that the finished product meets the specified requirements
3.2.3
type test
tests made before supplying on a general commercial basis a type of cable system or cable or accessory covered by this standard, in order to demonstrate satisfactory performance characteristics to meet the intended application
Note: Once successfully completed, these tests need not be repeated, unless changes are made in the cable or accessory with respect to materials, manufacturing process, design or design electrical stress levels, which might adversely change the performance characteristics.
3.2.4
prequalification test
test made before supplying on a general commercial basis a type of cable system covered by this standard, in order to demonstrate satisfactory long term performance of the complete cable system
3.2.5
extension of prequalification test
tests made before supplying on a general commercial basis a type of cable system covered by this standard, in order to demonstrate satisfactory long term performance of the complete cable system, taking into account an already prequalified cable system
3.2.6
electrical test after installation
tests made to demonstrate the integrity of the cable system as installed
3.3 Other definitions
3.3.1
cable system
cable with installed accessories including components used for thermo-mechanical restraint of systems limited to those used for terminations and joints only
3.3.2
nominal electrical stress
electrical stress calculated at U0 using nominal dimensions
Foreword I
Introduction IV
1 Scope
2 Normative References
3 Terms and Definitions
3.1 Definitions of dimensional values (thicknesses, cross-sections, etc.)
3.2 Definitions concerning tests
3.3 Other definitions
4 Voltage designations and materials
4.1 Rated voltages
4.2 Cable insulating materials
4.3 Cable metal screens/sheaths
4.4 Nonmetallic oversheathing materials of cable
5 Precautions against water penetration in cables
6 Cable characteristics
7 Accessory characteristics
8 Test conditions
8.1 Ambient temperature
8.2 Frequency and waveform of power frequency test voltages
8.3 Waveform of lightning impulse test voltages
8.4 Relationship of test voltages to rated voltages
8.5 Determination of the cable conductor temperature
9 Routine tests on cables and on the main insulation of prefabricated accessories
9.1 General
9.2 Partial discharge test
9.3 Voltage test
9.4 Electrical test on oversheath of the cable
10 Sample test on cables
10.1 General
10.2 Frequency of tests
10.3 Repetition of tests
10.4 Conductor examination
10.5 Measurement of electrical resistance of metal conductor and metal screen/sheath
10.6 Measurement of thickness of cable insulation and nonmetallic oversheath
10.7 Measurement of thickness of metal sheath
10.8 Measurement of diameters
10.9 Hot set test for XLPE insulations
10.10 Measurement of capacitance
10.11 Lightning impulse voltage test
10.12 Water penetration test
10.13 Tests on components of cables with a longitudinally applied metal tape or foil, bonded to the oversheath
11 Routine inspection
11.1 Tests on components
11.2 Tests on complete accessory
12 Type tests on cable systems
12.1 General
12.2 Range of type approval
12.3 Summary of type tests
12.4 Electrical type tests on complete cable systems
12.5 Non-electrical type tests on cable components and on complete cable
13 Prequalification test of the cable system
13.1 General and range of prequalification test approval
13.2 Prequalification test on complete system
13.3 Tests for the extension of the prequalification of a cable system
14 Type test on cables
14.1 General
14.2 Range of type approval
14.3 Summary of type tests
14.4 Electrical type tests on completed cables
15 Type tests on accessories
15.1 General
15.2 Range of type approval
15.3 Summary of type tests
15.4 Electrical type tests on accessories
16 Electrical tests after installation
16.1 General
16.2 DC voltage test of the nonmetallic oversheath
16.3 AC voltage test of the insulation
Annex A (Informative) Determination of the cable conductor temperature
Annex B (Normative) Rounding of numbers
Annex C (Informative) List of type, prequalification and extension of prequalification tests for cable systems, cables and accessories
Annex D (Normative) Method of measuring resistivity of semi-conducting screens
Annex E (Normative) Water penetration test
Annex F (Normative) Tests on components of cables with a longitudinally applied metal tape or foil, bonded to the oversheath
Annex G (Normative) Tests of outer protection for joints
Annex H (Normative) Test on interface protrusion between micropores, impurities and semi-conducting screens
Annex I (Informative) Structural changes between this part and IEC 60840:2011
Annex J (Informative) Technical changes and reasons between this Part and IEC 60840:2011
Bibliography
Figure 1 Example of the test arrangement for the prequalification test
Figure 2 Example of extension of prequalification test arrangement for the prequalification of a system with another joint, designed for rigid as well as flexible installation
Figure A.1 Typical test set-up for the reference loop and the main test loop
Figure A.2 Example of an arrangement of the temperature sensors on the conductor of the reference loop
Figure D.1 Preparation of samples for measurement of volume resistivity of conductor and insulation screens
Figure E.1 Schematic diagram of apparatus for water penetration test
Figure F.1 Adhesion strength of metal foil
Figure F.2 Example of overlapped metal foil
Figure F.3 Peel strength test of overlapped metal foil
Table 1 Insulating compounds for cables
Table 2 Nonmetallic oversheathing compounds for cables
Table 3 Tan δ requirements for insulating compounds for cables
Table 4 Test voltages
Table 5 Summary of the non-electrical type tests for insulating and oversheathing compounds for cables
Table 6 Test requirements for mechanical characteristics of XLPE insulating compounds for cables (before and after ageing)
Table 7 Test requirements mechanical properties of oversheathing compounds for cables (before and after ageing)
Table 8 Test requirements for particular characteristics of PVC oversheath materials for cables
Table 9 Test requirements for special properties of cable XLPE insulating compounds
Table C.1 Type tests on cable systems, on cables and on accessories
Table C.2 Prequalification tests on cable systems with a calculated nominal
conductor electric stress above 8.0 kV/mm or a calculated nominal insulation electric stress above 4.0 kV/mm
Table C.3 Extension of prequalification tests on cable systems with a calculated nominal conductor electric stress above 8.0 kV/mm or a calculated nominal insulation electric stress above 4.0 kV/mm
Table G.1 Impulse voltage tests
Table I.1 Comparison of clause numbers in this Part with that in IEC 60840:2011
Table J.1 Technical differences and their causes between this Part and IEC 60840:2011