BS 6622:2007 2008
$198.66
Electric cables. Armoured cables with thermosetting insulation for rated voltages from 3.8/6.6 kV to 19/33 kV. Requirements and test methods
| Published By | Publication Date | Number of Pages |
| BSI | 2008 | 60 |
This British Standard specifies requirements and test methods for the construction, dimensions and mechanical and electrical properties of armoured cables with thermosetting insulation for rated voltages from 3.8/6.6 (7.2) kV up to 19/33 (36) kV inclusive, designed for a maximum continuous conductor operating temperature of 90 °C and for a maximum short circuit conductor temperature of 250 °C, for use in fixed installations such as networks or industrial installations.
This British Standard specifies single-core and three-core cables for voltages in the range 3.8/6.6 (7.2) kV up to 19/33 (36) kV, with:
- a stranded copper, stranded aluminium or solid aluminium conductor or conductors;
- cross-linked polyethylene or cross-linked ethylene propylene rubber insulation;
- a metallic screening layer of copper wire or copper tape and/or a metallic armour of aluminium or galvanized steel wire;
- a polyvinyl chloride compound (PVC) or polyethylene (PE) oversheath.
NOTE Guidance on the selection of cables is given in Annex A. Information to be supplied by the purchaser, and items to be agreed between the purchaser and the manufacturer, at the time of enquiry and/or order, are given in Annex B. Recommendations for the installation of cables are given in Annex C. Guidance on the use of cables is given in Annex D.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 3 | Contents Foreword iii 1 Scope 1 2 Normative references 1 3 Terms and definitions 2 4 Voltage designation 4 5 Conductors 4 6 Conductor screen 4 7 Insulation 4 8 Insulation screen 5 9 Assembly of three-core cables, including inner coverings and fillers 5 10 Metallic layer 7 11 Metallic armour 8 12 Oversheath 9 13 Marking 10 14 End sealing 11 15 Schedule of tests 12 16 Test conditions 14 17 Routine tests 14 18 Sample tests 16 19 Type tests – Materials 21 20 Type tests – Electrical 24 Annexes Annex A (informative) Recommendations for the selection of cables 28 Annex B (normative) Information to be supplied and items to be agreed 32 Annex C (informative) Recommendations for the installation of cables 33 Annex D (informative) Guide to use of cables 36 Annex E (normative) Fictitious calculation method for determination of dimensions of protective coverings 39 Annex F (normative) Rounding of numbers 42 Annex G (informative) Guidance on the scope of type tests 43 Annex H (normative) Thickness measurements 45 Annex I (normative) Test method for cold strippability of the extruded semi-conducting layer of an insulation screen 46 Annex J (normative) Method for measurement of resistivity of extruded semi-conducting conductor screen and insulation screen 47 Annex K (normative) Method for measurement of resistivity of lapped inner covering 51 Annex L (normative) Wet compatibility test for galvanized steel wires and semi-conducting tape layers 51 Bibliography 53 List of figures Figure J.2 – Test piece and arrangement of electrodes for measurement of resistivity of the insulation screen 50 Figure L.1 – Test cell for wet compatibility test of galvanized steel wires and semi-conducting tape layers 52 |
| 4 | List of tables Table 1 – Nominal thickness of insulation 5 Table 2 – Thickness of extruded inner covering 6 Table 3 – Nominal diameter of round armour wires 8 Table 4 – Schedule of tests 12 Table 5 – Tolerances on temperature values 14 Table 6 – D.C. resistance of copper wire screen 15 Table 7 – Voltage for partial discharge test 15 Table 8 – Voltage for test on complete cable 16 Table 9 – Number of samples for the four-hour voltage test and the hot set test on the insulation 17 Table 10 – Voltages for four-hour voltage test 20 Table 11 – Mass of zinc coating 22 Table 12 – Conditions for oversheath shrinkage test 23 Table 13 – Compatibility requirements 24 Table 14 – Tan d in relation to voltage 25 Table 15 – Tan d in relation to temperature 26 Table 16 – Voltage for impulse voltage test 27 Table A.1 – Selection of cables for three-phase a.c. systems 30 Table C.1 – Bending radius during installation 33 Table C.2 – Bending radius during installation for cables adjacent to joints or terminations 33 Table E.1 – Fictitious diameter of conductor 40 Table E.2 – Increase of diameter for concentric conductors and metallic screens 41 |
| 5 | Foreword |
| 7 | 1 Scope 2 Normative references |
| 8 | 3 Terms and definitions 3.1 rated voltage 3.2 rated voltage U0 3.3 rated voltage U 3.4 maximum voltage Um 3.5 cross-linked polyethylene (XLPE) |
| 9 | 3.6 ethylene propylene rubber compound (EPR) 3.7 polyvinyl chloride compound (PVC) 3.8 polyethylene (PE) 3.9 nominal value 3.10 approximate value 3.11 fictitious value 3.12 routine tests 3.13 sample tests 3.14 type tests |
| 10 | 4 Voltage designation 5 Conductors 6 Conductor screen 7 Insulation |
| 11 | Table 1 Nominal thickness of insulation 8 Insulation screen 8.1 General 8.2 Extruded semi-conducting layer 9 Assembly of three-core cables, including inner coverings and fillers 9.1 General |
| 12 | 9.2 Inner coverings and fillers Table 2 Thickness of extruded inner covering 9.3 Cables with a collective metallic layer 9.4 Cables with a metallic layer over each individual core |
| 13 | 10 Metallic layer 10.1 General 10.2 Metallic screen on each core 10.3 Collective metallic screen |
| 14 | 11 Metallic armour 11.1 Construction 11.1.1 General Table 3 Nominal diameter of round armour wires 11.1.2 Material 11.1.3 Application of armour 11.1.3.1 Single-core cables 11.1.3.2 Three-core cables |
| 15 | 11.2 Separation sheath 12 Oversheath 12.1 General 12.2 Thickness of oversheath 12.3 Semi-conducting layer |
| 16 | 13 Marking 13.1 External marking |
| 17 | 13.2 Identification of year of manufacture 13.3 The mark of an approval organization 13.4 Additional marking 14 End sealing |
| 18 | 15 Schedule of tests Table 4 Schedule of tests |
| 19 | Table 4 Schedule of tests (continued) |
| 20 | 16 Test conditions 16.1 Ambient temperature 16.2 Tolerances on temperature values Table 5 Tolerances on temperature values 16.3 Frequency and waveform of power-frequency test voltages 17 Routine tests 17.1 General 17.2 Spark test on oversheath 17.3 Conductor resistance |
| 21 | 17.4 Copper wire screen resistance 17.4.1 Method 17.4.2 Requirement Table 6 D.C. resistance of copper wire screen 17.5 Partial discharge test Table 7 Voltage for partial discharge test |
| 22 | 17.6 Voltage test on complete cable Table 8 Voltage for test on complete cable 17.7 Cable markings 17.8 D.C. voltage test on oversheath 17.8.1 General 17.8.2 Method 17.8.3 Requirement 18 Sample tests 18.1 General 18.2 Sampling frequency |
| 23 | Table 9 Number of samples for the four-hour voltage test and the hot set test on the insulation 18.3 Repetition of sample tests 18.4 Conductor material and construction 18.5 Conductor screen 18.6 Hot set test on insulation |
| 24 | 18.7 Dimensions 18.7.1 Thickness of insulation 18.7.2 Concentricity of insulation 18.8 Circularity of cores 18.8.1 Method 18.8.2 Requirement 18.9 Insulation screen 18.9.1 Application 18.9.2 Cold strippability |
| 25 | 18.10 Metallic screen (wires only) 18.11 Assembly of three-core cables 18.12 Separation sheath 18.13 Semi-conducting lapped inner covering 18.14 Measurement of armour wires 18.15 Oversheath thickness |
| 26 | 18.16 Four-hour voltage test 18.16.1 Method 18.16.2 Requirement Table 10 Voltages for four-hour voltage test |
| 27 | 19 Type tests – Materials 19.1 General 19.2 Conductor screen resistivity 19.3 Insulation material 19.4 Insulation screen resistivity 19.5 Insulation screen cold strippability 19.6 Semi-conducting lapped inner covering resistivity 19.7 Separation sheath material 19.8 Mass of zinc coating of galvanized steel wires 19.8.1 Method |
| 28 | 19.8.2 Requirement Table 11 Mass of zinc coating 19.9 Wrapping test for galvanized steel wires 19.9.1 Method 19.9.2 Requirement 19.10 Wet compatibility test for galvanized steel wires and semi-conducting tape layers 19.10.1 Method 19.10.2 Requirements 19.11 Tensile test for aluminium wires 19.11.1 Method |
| 29 | 19.11.2 Requirement 19.12 Oversheath 19.12.1 Material 19.12.2 Shrinkage (type TS 2 only) Table 12 Conditions for oversheath shrinkage test 19.13 Compatibility test |
| 30 | Table 13 Compatibility requirements 19.14 Test under fire conditions for PVC sheathed cables 20 Type tests – Electrical 20.1 General 20.2 Partial discharge test |
| 31 | 20.3 Bending test 20.3.1 Method 20.3.2 Requirements 20.4 Tan d in relation to voltage Table 14 Tan d in relation to voltage 20.5 Tan d in relation to temperature 20.5.1 Method |
| 32 | 20.5.2 Requirements Table 15 Tan d in relation to temperature 20.6 Heating cycle test 20.6.1 Method 20.6.2 Requirement 20.7 Impulse voltage test |
| 33 | Table 16 Voltage for impulse voltage test |
| 34 | 20.8 Four-hour voltage test 20.9 Adherence of screens at short circuit temperature 20.9.1 Method 20.9.2 Requirement |
| 35 | Annex A (informative) Recommendations for the selection of cables A.1 General A.2 Voltage ratings a) Category A. This category comprises those systems in which any phase conductor that comes in contact with earth or an earth conductor is disconnected from the system within 1 min. b) Category B. This category comprises those systems which, under fault conditions, are operated for a short time with one phase… c) Category C. This category comprises all systems which do not fall into categories A or B. |
| 36 | A.3 Metallic coverings A.4 Selection of metallic coverings in relation to earth fault capacity |
| 37 | A.5 Semi-conducting layer on the oversheath a) when the oversheath is required to perform an insulating function during the operation of the cable. This applies when the me… b) when damage to the oversheath is likely to lead to corrosion of an essential metallic layer which it protects, due to an environment aggressive to the particular metal. A.6 Current carrying capacity |
| 38 | Annex B (normative) Information to be supplied and items to be agreed B.1 Information to be supplied by the purchaser at the time of enquiry and/or order a) length of cable required, and individual drum lengths, if particular drum lengths are required; b) voltage designation (see Clause 4); c) number of cores; d) size of phase conductor; e) conductor material (i.e. copper or aluminium) (see Clause 5); f) type of conductor (i.e. stranded or solid) (see Clause 5); g) type of insulation (i.e. XLPE or EPR) and limiting dimensions (if any) of the cores; h) whether the insulation screen is required to be cold strippable (see 8.2); i) type of metallic insulation screen (see Clause 10); j) cross-sectional area of metallic insulation screen; k) if an armour layer with a special construction is required which requires the armour to be made of magnetic material (see 11.1.2); l) if a steel armour layer with a specific minimum conductance is required (see 11.1.2 Note); m) type of oversheath (i.e. PVC or PE); n) nominal thickness of oversheath if a thickness other than that specified in 12.2 is required; o) if a d.c. voltage test on the oversheath is required (see 12.3 and 17.8). B.2 Items to be agreed between the purchaser and the manufacturer a) colour of the oversheath if a colour other than black is required (see 12.1 Note); b) sampling frequency for sample tests if different from that specified in 18.2. |
| 39 | Annex C (informative) Recommendations for the installation of cables C.1 Minimum temperature during installation C.2 Minimum installation radius Table C.1 Bending radius during installation Table C.2 Bending radius during installation for cables adjacent to joints or terminations C.3 Prevention of moisture ingress |
| 40 | C.4 Joints and terminations a) moulded components; b) various tapes; c) heat shrinkable tubes. C.5 Compound filling |
| 41 | C.6 Earthing of armour and screen(s) C.7 Tests after installation C.7.1 Tests on insulation a) The cable should be tested for 5 min with the phase-to-phase voltage of the system applied between the conductor and the metallic screen or sheath. b) The cable should be tested for 24 h with the normal operating voltage. |
| 42 | C.7.2 D.C. voltage test on oversheath Annex D (informative) Guide to use of cables D.1 General D.2 Cable selection in relation to installation design a) In a solidly or directly earthed system, in general the earth fault current is at least equal to the three-phase or phase-to-phase fault current. b) When an earth fault current is specified for a system, it is necessary to ensure that the phase conductor of the cable selected has a corresponding earth fault capacity. c) Some work on spiking of cables has been undertaken by the British cable industry and it has shown that, in general, the spiking capability of the screen(s) is less than their through fault capacity. |
| 43 | d) This standard specifies different forms of metallic screen having different earth fault capacities. In general, copper tape s… e) It is essential that connections at joints between, and terminations onto, metallic elements carrying fault currents to earth have an earth fault capacity at least equal to that of the metallic elements. D.3 Environmental factors a) for use as self supporting aerial cables; b) for use as submarine cable or for laying in waterlogged conditions; c) for use in situations where subsidence is likely, unless special precautions are taken to minimize damage if subsidence should occur; d) for use in situations where they could be exposed to excessive heat. D.4 Installation |
| 44 | D.5 Storage and handling of drums D.6 Incineration of scrap cable |
| 45 | Annex E (normative) Fictitious calculation method for determination of dimensions of protective coverings E.1 General |
| 46 | E.2 Method E.2.1 Conductors Table E.1 Fictitious diameter of conductor E.2.2 Cores E.2.3 Diameter over laid-up cores E.2.4 Inner coverings a) three-core cables: b) single-core cables: |
| 47 | E.2.5 Concentric conductors and metallic screens Table E.2 Increase of diameter for concentric conductors and metallic screens a) tape screen b) wire screen (with a counter helix, if any) |
| 48 | E.2.6 Separation sheath E.2.7 Armour Annex F (normative) Rounding of numbers F.1 Rounding of numbers for the purpose of the fictitious calculation method 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 shall remain unchanged (i.e. the value shall be rounded down). |
| 49 | b) When the figure in the second decimal place, before rounding, is 5, 6, 7, 8 or 9, then the figure in the first decimal place shall be increased by one (i.e. the value shall be rounded up). F.2 Rounding of numbers for other purposes a) If the last figure to be retained is followed, before rounding, by 0, 1, 2, 3 or 4, it shall remain unchanged (i.e. the value shall be rounded down); b) If the last figure to be retained is followed, before rounding, by 5, 6, 7, 8 or 9, it shall be increased by one (i.e. the value shall be rounded up). Annex G (informative) Guidance on the scope of type tests G.1 General |
| 50 | G.2 Invoking of type tests G.3 Sequential electrical type tests |
| 51 | G.4 Compatibility test (see 19.13) G.5 Type tests on components G.6 Evidence of type testing Annex H (normative) Thickness measurements H.1 Sampling |
| 52 | H.2 Procedure a) for the insulation: the minimum thickness and the maximum thickness; b) for the separation sheath: the minimum thickness; c) for the oversheath: the minimum thickness. Annex I (normative) Test method for cold strippability of the extruded semi-conducting layer of an insulation screen |
| 53 | Annex J (normative) Method for measurement of resistivity of extruded semi- conducting conductor screen and insulation screen J.1 Preparation of test pieces J.2 Procedure J.3 Calculations J.3.1 Conductor screen |
| 54 | J.3.2 Insulation screen |
| 55 | Figure J.1 Test piece and arrangement of electrodes for measurement of resistivity of the conductor screen |
| 56 | Figure J.2 Test piece and arrangement of electrodes for measurement of resistivity of the insulation screen |
| 57 | Annex K (normative) Method for measurement of resistivity of lapped inner covering Annex L (normative) Wet compatibility test for galvanized steel wires and semi-conducting tape layers |
| 58 | Figure L.1 Test cell for wet compatibility test of galvanized steel wires and semi-conducting tape layers |
| 59 | Bibliography [1] Conférence Internationale des Grands Réseaux Electriques. Report 1968-21-01 . [2] Institute of Electrical and Electronics Engineers. Paper No. 69, CP88-PWR . |
