BS 7922-2004 Electric cables - Fluid-filled paper- and PPL-insulated metal-sheathed cables and accessories for alternating voltages up to and including 400 kV (Um = 420 kV) - Requi.pdf

1、BRITISH STANDARD BS 7922:2004 Electric cables Fluid-filled, paper- and PPL-insulated, metal-sheathed cables and accessories for alternating voltages up to and including 400 kV (U m =42 0kV) Requirements and test methods (Implementation of HD 633) ICS 29.060.20 BS 7922:2004 This British Standard, was

2、 published under the authority of the Standards Policy and Strategy Committee on 4 August 2004 BSI 4 August 2004 The following BSI references relate to the work on this British Standard: Committee reference GEL/20/16 Draft for comment 95/215974 DC ISBN 0 580 38553 1 Committees responsible for this B

3、ritish Standard The preparation of this British Standard was entrusted by Technical Committee GEL/20, Electric cables, to Subcommittees GEL/20/16, Medium/high voltage cables, upon which the following bodies were represented: British Approvals Service for Cable British Cables Association British Plas

4、tics Federation Energy Networks Associations ERA Technology Ltd. Co-opted members Amendments issued since publication Amd. No. Date CommentsBS 7922:2004 BSI 4 August 2004 i Contents Page Committees responsible Inside front cover Foreword ii 1S c o p e 1 2 Normative references 1 3T e r m s a n d d e

5、f i n i t i o n s 2 4 Voltage designation 2 5 Characteristics of cables and accessories 3 6 Test categories, frequency and conditions 3 7 Routine tests on cables 5 8 Sample tests on cables 7 9 Routine tests on accessories 9 10 Sample tests on accessories 10 11 Type tests on cables and accessories 11

6、 12 Non-electrical type tests on cables 17 13 Non-electrical type tests on accessories 20 14 Tests and requirements for direct reading pressure gauges 22 15 Tests after installation 28 16 Tests on ancillary equipment 32 Annex A (informative) Methods of heating cable samples 40 Annex B (informative)

7、Pressure drop 40 Bibliography 41 Figure 1 Diagram showing internal electrical connections 25 Table 1 Number of samples for sample tests 4 Table 2 Tan measurement requirements for paper insulated cables 6 Table 3 Tan measurement requirements for PPL insulated cables 6 Table 4 Standard values of syste

8、m voltages and test voltages recommended for cables to be used in 3-phase systems 7 Table 5 Test cylinder diameters for bending test 8 Table 6 Internal test pressure 9 Table 7 Pressure/volume characteristics 10 Table 8 Waveshape 15 Table 9 Voltage levels 15 Table 10 Lightning impulse test voltage le

9、vels 17 Table 11 Impulse voltage test levels 21 Table 12 Salt fog test voltage levels 21 Table 13 Classification of gauges 22 Table 14 Climatic chamber temperatures for temperature limit tests 26 Table 15 High voltage test levels 29 Table 16 SVL test parameters 29 Table 17 Maximum contact resistance

10、 values 30 Table 18 Construction of single core bonding leads 33 Table 19 Construction of concentric bonding leads 33 Table 20 Test voltages for bonding leads 35 Table 21 Conductor resistance 35 Table 22 Short circuit requirements 37 Table 23 Impulse voltage withstand levels 39BS 7922:2004 ii BSI 4

11、August 2004 Foreword This British Standard has been prepared by Subcommittee GEL/20/16. It implements the nationally applicable parts of Harmonization Document HD 633 published by the European Committee for Electrotechnical Standardization (CENELEC), in accordance with the decision of the CENELEC Te

12、chnical Board. BS 7922 applies to fluid-filled, paper- and PPL-insulated, metal-sheathed cables and accessories for alternating voltages up to and including 400 kV (U m = 420 kV). It has been assumed in the preparation of this British Standard that the execution of its provisions will be entrusted t

13、o appropriately qualified and experienced people, for whose use it has been produced. 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

14、 legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to ii, pages 1 to 41 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.BS 7922:2004 BSI 4 August 2004 1 1 Scope This British Stan

15、dard specifies tests and requirements for radial field, fluid-filled, paper or polypropylene paper laminate (PPL) insulated metal-sheathed cables and their accessories, which operate with a minimum static pressure of between 20 kPa (0.2 bar) and 300 kPa (3.0 bar) inclusive, a maximum static pressure

16、 of not more than 800 kPa (8.0 bar) and a minimum transient pressure of not less than 20 kPa (0.2 bar) 1) . NOTE The cables in this British Standard are specifically excluded from the scope of the Pressure Equipment Directive. It also specifies tests for cables and accessories with maximum static pr

17、essures exceeding 800 kPa (8.0 bar). This British Standard is applicable to cables and accessories intended for use in systems with nominal voltages not exceeding 400 kV between phases. 2 Normative references The following referenced documents are indispensable for the application of this document.

18、For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. BS 228:1994, Specification for short-pitch transmission precision roller chains and chain wheels. BS 4727-2:Group 08, Glossary of electrotec

19、hnical, power, telecommunication, electronics, lighting and colour terms Part 2: Terms particular to power engineering Group 08: Electric cables. BS 6346, Specification for 600/1 000 V and 1 900/3 300 V armoured electric cables having PVC insulation. BS 6500:2000, Electric cables Flexible cords rate

20、d up to 300/500 V, for use with appliances and equipment intended for domestic, office and similar environments. BS 7912, Power cables with XLPE insulation and metallic sheath, and their accessories, for rated voltages from 66 kV (U m= 72.5 kV) to 132 kV (U m= 145kV) Requirements and test methods. B

21、S EN 50062, Specification for ceramic pressurized hollow insulators for high-voltage switchgear and controlgear. BS EN 60068-2-1, Environmental testing Part 2: Test methods Section 2-1: Tests A Cold. BS EN 60068-2-2, Environmental testing Part 2: Test methods Section 2-2: Tests B Dry heat. IEC 60060

22、-1, High-voltage test techniques Part 1: General definitions and test requirements. 2) IEC 60060-2, High-voltage test techniques Part 2: Measuring systems. IEC 60228:1978, Conductors of insulated cables. 3) IEC 60229:1982, Tests on cable oversheaths which have a special protective function and are a

23、pplied by extrusion. IEC 60230, Impulse tests on cables and their accessories. 4) IEC 60507:1991, Artificial pollution tests in high-voltage insulators to be used on a.c. systems. IEC 60554-2, Specification for cellulose papers for electrical purposes Part 2: Methods of test. IEC/TS 60859, Cable con

24、nections for gas-insulated metal-enclosed switchgear for rated voltages of 72,5 kV and above Fluid-filled and extruded insulation cables Fluid-filled and dry type cable-terminations. 1) These pressures are above atmospheric pressure. 2) Published by BSI as BS 923-1. 3) Published by BSI as BS 6360. 4

25、) Implemented by CENELEC as HD 48.BS 7922:2004 2 BSI 4 August 2004 3 Terms and definitions For the purposes of this British Standard, the definitions given in BS 4727-2:Group 08 and the following apply. 3.1 cables screened with carbon-black paper cables where carbon-black paper is applied as a scree

26、n over the conductor and where the carbon-black paper is in contact with the insulation 3.2 cables not screened with carbon-black paper cables where the screen over the conductor consists of any material other than carbon-black paper, or is such that carbon-black paper, if present, is not in contact

27、 with the insulation NOTE For the purpose of this British Standard, cables with unscreened conductors are included in this group. 3.3 rated voltage U 0 nominal power-frequency voltage between conductor and core screen for which the cable and its accessories are suitable 3.4 rated voltage U nominal p

28、ower-frequency voltage between any two conductors for which the cable and its accessories are suitable 3.5 maximum voltage U m maximum value of the highest permissible system voltage for which the cable and its accessories are suitable 3.6 peak voltage U p peak value of the impulse withstand voltage

29、 for which the cable and its accessories are suitable 4 Voltage designation Cables and accessories shall be designated by the rated voltage between conductor and core screen U 0and by the rated voltage between conductors U, both in kilovolts, e.g. 76/132 kV. Cables shall be operated in a system of t

30、he following categories. a) Category A comprises those systems where earth faults are cleared as rapidly as possible by in any case within 1 min. b) Category B comprises those systems which, under fault conditions, are operated for a short time with one phase earthed. NOTE According to IEC 60183, th

31、is period should not exceed 1 h. For cables in this British Standard, a longer period not exceeding 8 h on any occasion can be tolerated. The total duration of earth faults per year should not exceed 125 h. c) Category C: cables covered by BS 7922 are not intended for operating in category C systems

32、. Where there is such a requirement, agreement on the design of cables and accessories shall be made between the purchaser and the manufacturer.BS 7922:2004 BSI 4 August 2004 3 5 Characteristics of cables and accessories For the purpose of carrying out and recording the tests described in this Briti

33、sh Standard, the following characteristics shall be known or declared for each cable tested: a) rated voltage U 0 , in kilovolts (kV); b) lightning impulse withstand voltage U p , in kilovolts (kV); NOTE 1 The lightning impulse withstand voltage U pspecified above for each particular cable should be

34、 selected in accordance with IEC 60071-1. c) type of conductor, material, nominal cross-sectional area of the conductors in square millimetres (mm 2 ), and conductor resistance (for conductor resistances, see 7.2); d) conductor resistance, if the nominal cross-sectional area is not in accordance wit

35、h the values given in IEC 60228; e) number of cores; f) capacitance between each conductor and core screen, in microfarads per kilometre ( 4F/km); g) maximum permissible conductor temperature, in degrees Celsius ( C), for continuous operation under the specified ambient and installation conditions;

36、h) minimum and maximum permissible static fluid pressure, in kilopascals (kPa) or bars 5) ; i) type and material of the metallic sheath and the construction of the sheath reinforcement, if any; j) thermal resistance between conductor(s) and metallic sheath, in kelvin metres per watt (K m/W); NOTE 2

37、The thermal resistance should be calculated using the formulae given in IEC 60287-2-1. k) cable design stress, in kilovolts per millimetre (kV/mm); l) maximum design pressures of accessories, in kilopascals (kPa) (see Clause 9); m) type of conductor screen (with or without carbon-black paper); n) sp

38、ecified minimum thickness of insulation, nominal thickness of the metallic sheath and anti- corrosion covering, in millimetres (mm); o) nominal outside diameter of the cable and conductor, in millimetres (mm); p) type and material of the corrosion-resistant covering over the metallic sheath. The fol

39、lowing additional characteristics shall be stated by the manufacturer when requested by the purchaser: 1) maximum current rating in amperes (A) under the specified installation and operating conditions; 2) estimated effective (a.c.) resistance in ohms per kilometre ( 7/km) of the cable at the maximu

40、m operating temperature and under the specified installation conditions; 3) estimated inductance in henrys per kilometre (H/km) per phase of the completed cable under the specified installation conditions. 6 Test categories, frequency and conditions 6.1 Categories of tests NOTE Tests classified as s

41、ample or routine might be required as part of any type approval scheme. 6.1.1 Routine tests Tests made on all production cable lengths and accessories to demonstrate their integrity. 6.1.2 Sample tests Test made on samples of completed cable or accessories, or components taken from a completed cable

42、 or accessory, adequate to verify whether the finished product meets the design specifications. 5) 1 bar = 10 5 N/m 2= 10 5Pa.BS 7922:2004 4 BSI 4 August 2004 6.1.3 Type tests Test required to be made before supplying a type of cable or accessory covered by this standard on a general commercial basi

43、s in order to demonstrate satisfactory performance characteristics to meet the intended application. 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, design or type of manufacturing process, which might change

44、 the performance characteristics. 6.1.4 Tests after installation Tests intended to demonstrate the integrity of the cable and its accessories after installation and before use. 6.2 Frequency of tests 6.2.1 Frequency of measurements of dimensions This test shall be carried out on not more than 10 % o

45、f the number of delivery lengths, on at least one length, unless otherwise specified by the purchaser at the time of enquiry. 6.2.2 Frequency of mechanical tests Provided that the total length of cable supplied to the purchaser under a single contact exceeds 2 km of 3-core cable or 4 km of single co

46、re cable, tests shall be carried out in accordance with the number of samples specified in Table 1. Table 1 Number of samples for sample tests 6.3 Test conditions 6.3.1 Ambient temperature Unless otherwise specified in the details for the particular test, tests shall be made at an ambient temperatur

47、e of (20 15) C. 6.3.2 Frequency of waveform of power frequency test voltage The frequency of the alternating test voltages shall be in the range 49 Hz to 61 Hz. The waveform shall be substantially sinusoidal. NOTE The test voltage values quoted are r.m.s. values. 6.3.3 Waveform of impulse test volta

48、ge In accordance with IEC 60230, the impulse wave shall have a virtual front time between 1 4s and 5 4s and a nominal time to half the peak value between 40 4s and 60 4s. In other respects the impulse wave shall be in accordance with IEC 60060-1. Cable length Number of samples 3-core cables Single c

49、ore cables Above Up to and including Above Up to and including km km km km 21 0 42 0 1 10 20 20 40 2 20 30 40 60 3 etc. etc. etc. etc. etc.BS 7922:2004 BSI 4 August 2004 5 7 Routine tests on cables 7.1 General 7.1.1 The tests specified in 7.2, 7.3, 7.4, 7.5 and 7.6 shall be carried out as routine tests (see 6.1.1) on all completed cables in a single contract. 7.1.2 For the tests specified in 7.3, 7.4 and 7.5, the cable