BS-7870-6.3-1999.pdf

BRITISH STANDARD BS 7870-6.3:1999 Incorporating Amendment No. 1 LV and MV polymeric insulated cables for use by distribution and generation utilities Part 6: Specification for 0.6/1 kV and 1.9/3.3 kV power cables with special fire performance for use in power stations Section 6.3: Cables with thermosetting insulation and non-halogenated sheath (Implementation of HD 604) ICS 29.060.20 ? Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 This British Standard, having been prepared under the direction of the Electrotechnical Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 July 1999 © BSI 5 February 2004 The following BSI references relate to the work on this standard: Committee reference GEL/20/2 Draft for comment 96/204692 DC ISBN 0 580 33001 X Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee GEL/20, Electric cables, to Subcommittee GEL/20/2, Mains cables 1 kV and above, upon which the following bodies were represented: Association of Consulting Engineers British Approvals Service for Cables British Cables Association British Plastics Federation ERA Technology Ltd. Electricity Association London Underground Ltd. UK Steel Association Amendments issued since publication Amd. No.DateComments 143375 February 2004See foreword Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 © BSI 5 February 2004 i Contents Page Committees responsibleInside front cover Forewordiii 1Scope1 2Normative references1 3Voltage designation1 4General requirements2 5Cables without metallic covering7 6Cables with metallic covering7 Annex A (informative) Guide to use35 Bibliography39 Table 1 Requirements for the non-electrical tests for 90 °C insulation9 Table 1a) Special type tests for Type 2 cables11 Table 2 Requirements for the non-electrical tests for non-halogenated bedding and oversheath12 Table 3 Schedule of tests16 Table 4 Single-core 600/1 000 V cables with circular stranded copper or aluminium conductor (Type 1 and Type 2)17 Table 5 Single-core 600/1 000 V cables with solid aluminium conductor (Type 1 only)18 Table 6a) Two-core 600/1 000 V cables with stranded copper conductors when insulated with XLPE or HEPR (Type 1 and Type 2)19 Table 6b) Two-core 600/1 000 V cables with stranded copper conductors when insulated with TI Z (Type 2)19 Table 7 Two-core 600/1 000 V cables with solid aluminium conductors when insulated with XLPE or HEPR (Type 1 and Type 2)20 Table 8a) Three-core 600/1 000 V cables with stranded copper conductors when insulated with XLPE or HEPR (Type 1 and Type 2)21 Table 8b) Three-core 600/1 000 V cables with stranded copper conductors when insulated with TI Z (Type 2)21 Table 9 Three-core 600/1 000 V cables with solid aluminium conductors when insulated with XLPE or HEPR (Type 1 and Type 2)22 Table 10a) Four-core 600/1 000 V cables with stranded copper conductors when insulated with XLPE or HEPR (Type 1 and Type 2)23 Table 10b) Four-core 600/1 000 V cables with stranded copper conductors when insulated with TI Z (Type 2)23 Table 11 Four-core 600/1 000 V cables with solid aluminium conductors when insulated with XLPE or HEPR (Type 1 and Type 2)24 Table 12 Four-core 600/1 000 V cables with reduced neutral conductor and with stranded copper conductors (Type 1 only)25 Table 13 Five-core 600/1 000 V cables with stranded copper conductors (Type 1)25 Table 14 600/1 000 V armoured auxiliary cables with stranded copper conductors (Type 1 only)26 Table 15 Single-core 1 900/3 300 V cables with circular stranded aluminium or copper conductors (Type 1 and Type 2)27 Table 16 Three-core 1 900/3 300 V cables with stranded copper conductors (Type 1 and Type 2)27 Table 17 Three-core 1 900/3 300 V cables with solid aluminium conductors (Type 1 and Type 2)28 Table 18 Mass of zinc coating and diameter of armour wire28 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 ii© BSI 5 February 2004 Page Table 19 Maximum resistance of conductor and armour for single-core cables having aluminium wire armour (Type 1 and Type 2)29 Table 20 Maximum resistance of conductor and armour for two-core, three-core, four-core and five-core cables having wire armour (Type 1 and Type 2)30 Table 21 Maximum resistance of armour for twin, three- and four-core cables having copper conductors and steel wire armour (Type 2 with TI Z insulation)31 Table 22 Maximum resistance of conductor and armour for 600/1 000 V auxiliary cables with copper conductors having steel wire armour (Type 1 only)31 Table 23 Gross cross-sectional areas of armour wires for single-core 600/1 000 V cables having aluminium wire armour (Type 1 and Type 2)32 Table 24 Gross cross-sectional areas of armour wires for two-, three-, four- and five-core 600/1 000 V cables having wire armour (Type 1 and Type 2)33 Table 25 Gross cross-sectional areas of armour wires for 600/1 000 V auxiliary cables with copper conductors having steel wire armour (Type 1 only)33 Table 26 Requirements for compatibility test34 Table A.1 Selection of cables for a.c. systems35 Table A.2 Test voltage after installation37 Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 © BSI 5 February 2004 iii Foreword BS 7870 was prepared by Subcommittee GEL/20/2. It implements the nationally applicable parts of Harmonisation Documents HD 603, 604, 605, 620, 622, 626 and 627, published by the European Committee for Electrotechnical Standardization (CENELEC), in accordance with the decision of the CENELEC Technical Board. The start and finish of text introduced or altered by amendment is indicated in the text by tags !“. Tags indicating changes to text carry the number of the amendment. For example, text altered by amendment No. 1 is indicated by !“. BS 7870 applies to cables for fixed installations having a rated voltage Uo/U up to and including 1.9/3.3 kV, and is published as a series of separate parts and sections, as listed in the table in the foreword of Part 1. This section of BS 7870 is to be read in conjunction with BS 7870-1 and BS 7870-2. This section of BS 7870 implements Part 5E of HD 604 and HD 604 A1. The cable types included in this section are listed below: a) 2-, 3-, 4- and 5-core cables having copper conductor and steel wire armour; b) 2-, 3- and 4-core cables having solid aluminium conductors and aluminium wire armour; c) single-core cables having stranded copper, stranded aluminium, solid or sectoral aluminium conductors and aluminium wire armour; d) multicore auxiliary cables having stranded copper conductors and steel wire armour. A “Guide to use” for the above cables is given in Annex A. Annex A is informative. Amendment No. 1:2004 implements the changes to the identification of cores by colours, in accordance with HD 308 S2. The principal identification colours are now: Single phase Green-and-yellow (Earth); blue (Neutral); brown (Live). Three phase Green-and-yellow (Earth); blue (Neutral); brown, black, grey (Live). Users should ensure that any interconnection between cables with these new colours and those with the pre-existing ones is carried out safely. BS 7671, as amended in parallel with this standard, gives some guidance in this respect, but does not cover all installation conditions or cable uses. The provisions introduced by amendment No. 1:2004 are effective from 1stApril 2004. The original version of this standard remains current until 31stMarch 2006. It has been assumed in the preparation of this British Standard that the execution of its provisions will be entrusted to appropriately qualified and experienced people, for whose use it has been produced. WARNING. This British Standard calls for the use of substances and/or procedures that may be injurious to health if adequate precautions are not taken. It refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety at any stage. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 39 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 © BSI 5 February 2004 1 1 Scope This section of BS 7870 specifies requirements and dimensions of single- and multicore cables with thermosetting insulation and non-halogenated sheath having reduced fire propagation performance and having low emission of smoke when affected by fire. The cables are designed for a maximum continuous conductor operating temperature of 90 °C and for a maximum short circuit temperature of 250 °C. Two types of cable are covered by this section of BS 7870: Type 1 and Type 2. The basis for the two types is as follows. Type 1: cable intended to satisfy the installation and operating conditions prevailing in a fossil-fuelled power station or equivalent location. Type 2: cable intended to satisfy the installation and operating conditions prevailing in a PWR power station, but excluding locations in or around the containment area. NOTE 1The cable type should be selected which is appropriate to the application. NOTE 2The general construction requirements are the same for both types. However, Type 2 cables have the option of dual-layer oversheaths and, for some types, of employing TI Z insulation with associated increase in thickness of insulation, bedding and oversheath. NOTE 3The more onerous type testing of Type 2 cables acknowledges the limited size range and voltage of cables currently used in certain PWR projects. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of this British Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. For undated references, the latest edition of the publication referred to applies. !Text deleted“ BS 6360, Specification for conductors in insulated cables and cords. !Text deleted“ BS 7870-1:1996, LV and MV polymeric insulated cables for use by distribution and generation utilities Part 1: General. BS 7870-2:1999, LV and MV polymeric insulated cables for use by distribution and generation utilities Part 2: Methods of test. !BS EN 50265-2-1:1999, Common test methods for cables under fire conditions Test for resistance to vertical flame propagation for a single insulated conductor or cable Part 2-1: Procedures 1 kW pre-mixed flame. BS EN 50268-2, Common test methods for cables under fire conditions Measurement of smoke density of cables burning under defined conditions Part 2: Procedure.“ BS EN 60811-1.2, Insulation and sheathing materials of electric cables Part 1: Methods for test for general applications Section 1.2: Thermal ageing methods. BS ISO 4589-2, Plastics Determination of burning behaviour by oxygen index Part 2: Ambient temperature test. 3 Voltage designation Cables are designated by the voltage U0, U and Um expressed in the form U0/U (Um). The voltage designations of cables in this standard are: 0.6/1 (1.2) kV; 1.9/3.3 (3.6) kV. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 2© BSI 5 February 2004 4 General requirements 4.1 Identification of cores The cores of all cables shall be identified either by numbers or by colours in accordance with the following sequence: The height of individual numbers shall be not less than 1.5 mm and the interval between adjacent numbers shall not exceed 70 mm. !NOTEThe core colour blue now denotes the neutral conductor.“ 4.2 Thickness of bedding The minimum thickness of extruded bedding shall be not less than the specified value for each type and size of cable shown in the tables by an amount more than 20 % + 0.2 mm. Conformity shall be checked by the test given in BS 7870-2, 2.1.2. 4.3 Cable marking The method of cable marking shall conform to the following requirements. 4.3.1 External marking The external surface of all cables shall be legibly marked with the following elements of marking. The marking of items a) to d) shall be by embossing or indenting on the oversheath or by other durable means agreed with the purchaser. For cables with tabulated approximate overall diameters above 15 mm, items a), b) and c) shall appear, in any sequence that neither confuses nor conflicts, on two or more primary lines along the axis of the cable, approximately equally spaced around the circumference of the cable. Items d) and e) shall appear on at least one line, which may be one of the primary lines, or a secondary line or lines. They may appear in any sequence that neither confuses nor conflicts, and need not all be on the same line. ! Number of cores Identification One Brown or blue Two Brown, blue Three Brown, black, grey Four Blue, brown, black, grey Five Green-and-yellow, blue, brown, black, grey Auxiliary cables 1, 2, 3, 4, 5, 6, 7 and upwards“ Element Example of marking a) Electric Cable ELECTRIC CABLE b) Voltage designation 600/1 000 V 600/1 000 V AUX 1 900/3 300V c) Standard number BS 7870-6.3 Type 1 (or Type 2) d) Manufacturers identification XYZ e) Number of cores, type and nominal area of conductor, e.g. 1) Copper conductor cables: 4 × 50 (4 × 50 indicates a 4-core cable with 50 mm2 copper conductors). 2) Aluminium conductor cables: 4 × 50 AL (4 × 50 AL indicates a 4-core cable with 50 mm2 aluminium conductors). 3) Copper conductor cables with reduced neutral: 3 × 50/25 (3 × 50/25 indicates a 4-core cable with three 50 mm2 copper phase conductors and one 25mm2 copper neutral conductor). Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 12:10:19 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 7870-6.3:1999 © BSI 5 February 2004 3 For cables with tabulated approximate overall diameters of 15 mm or smaller, the items shall be dispos