ASTM F855-2017 Standard Specifications for Temporary Protective Grounds to Be Used on De-energized Electric Power Lines and Equipment 《断电电力线路和设备用临时保护接地的标准规范》.pdf

1、Designation: F855 15F855 17Standard Specifications forTemporary Protective Grounds to Be Used on De-energizedElectric Power Lines and Equipment 1This standard is issued under the fixed designation F855; the number immediately following the designation indicates the year of originaladoption or, in th

2、e case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These specifications cover the equipment making up the temporary grounding system used on

3、de-energized electric powerlines, electric supply stations, and equipment.1.2 It is common practice for the users of protective grounding equipment to prepare complete instructions and regulations togovern in detail the correct use and maintenance of such equipment.1.3 The uses and maintenance of th

4、is equipment are beyond the scope of these specifications.1.4 These specifications for a system of protective grounding utilizing copper cables are covered in four parts, as follows:SectionsClamps for Temporary Protective Grounds 4 16Ferrules for Temporary Protective Grounds 17 30Cables for Temporar

5、y Protective Grounds 31 39Protective Grounds (Complete Assembly With Clamps, Ferrules,and Cable)40 521.5 Each of the four parts is an entity of itself, but is listed as a part of the system for completeness and clarification.1.6 Currents presented in Table 1 are based upon cable melting times, as de

6、termined from equations by I. M. Onderdonk andare to used in situations involving an asymmetry value less than 20 % (X/R 1.8). See Appendix X3X1.1.6.1 Currents presented in Table 2 are based upon the values from EPRI Project RP2446 Computer Program RTGC “ADesktopComputer Program for Calculating Rati

7、ng of Temporary Grounding Cables” and are to be used in situations involving anasymmetry value greater then 20 % (X/R 1.8), see Appendix X4X2.NOTE 1Table 1 represents the clamp and assembly ratings that existed prior to this revision. Table 2 represents new ratings now required for highX/R situation

8、s.1.6.2 See Appendix X3X1 and Appendix X4X2 for a discussion of these topics.1.7 The values stated in Newton-Meter units are to be regarded as the standard. The values in parentheses are the inch-poundunits.1.8 The following precautionary caveat pertains to the test method portions, Sections 12 and

9、25 of these specifications: Thisstandard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the applicabilityof r

10、egulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Or

11、ganization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2B172 Specification for Rope-Lay-Stranded Copper Conductors Having Bunch-Stranded Members, for Electrical Conductors1 These specifications are under the jurisdiction ofASTM Committee F18 on Electrical Pr

12、otective Equipment for Workers and are the direct responsibility of SubcommitteeF18.45 on Mechanical Apparatus.Current edition approved June 1, 2015Dec. 15, 2017. Published July 2015January 2018. Originally approved in 1983. Last previous edition approved in 20142015 asF855 14.F855 15. DOI: 10.1520/

13、F0855-15.10.1520/F0855-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standa

14、rd and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases

15、only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1B173 Specification for Rope-Lay-Stranded Copper Conductors Having Concentric-Strand

16、ed Members, for Electrical Conduc-torsD470 Test Methods for Crosslinked Insulations and Jackets for Wire and CableD753 Specification for General Purpose Polychloroprene Jacket for Wire and Cable (Withdrawn 1984)3D2219 Specification for Poly(Vinyl Chloride) Insulation for Wire and Cable, 60C Operatio

17、nD2633 Test Methods for Thermoplastic Insulations and Jackets for Wire and CableD2768 Specification for General-Purpose Ethylene-Propylene Rubber Jacket for Wire and Cable (Withdrawn 2007)3D2770 Specification for Ozone-Resisting Ethylene-Propylene Rubber Integral Insulation and Jacket for Wire and C

18、able(Withdrawn 2007)3E8/E8M Test Methods for Tension Testing of Metallic Materials2.2 ANSI Standard:4C 37.09 Standard Test Procedure for AC High-Voltage Circuit Breakers Rated on a Symmetrical Basis2.3 ICEA/NEMA Standard:5ICEA S-19-81/NEMAWC 3-80 (R 1986) Rubber Insulated Wire and Cable for the Tran

19、smission and Distribution of ElectricalEnergy2.4 IEC Standard:6IEC 61230 Ed. 2, 2008, Portable Equipment for Earthing or Earthing and Short-Circuiting2.5 IEEE Standard:7IEEE 386 Standard for Separable Insulated Connector Systems for Power Distribution Systems Above 600VIEEE 1048 Guide for Protective

20、 Grounding of Power LinesIEEE 1246 Guide for Temporary Protective Grounding Systems Used in Substations3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 continuous current ratingdesignated RMS current which can be carried continuously under specified conditions.3.1.2 protective

21、ground assemblya temporary electrical connection between a source of potential energization and the earth,rated for the maximum anticipated fault current or continuous induced current, or both.3.1.2.1 Discussion3 The last approved version of this historical standard is referenced on www.astm.org.4 A

22、vailable from American National Standards Institute, 11 West 42nd St., 13th Floor, New York, NY 10036.5 Available from Insulated Cable Engineers Assoc., P.O. Box P, South Yarmouth, MA 02664.6 Available from International Electrotechnical Commission (IEC), 3 rue de Varemb, Case postale 131, CH-1211,

23、Geneva 20, Switzerland, http:/www.iec.ch.7 Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE), 445 Hoes Ln., P.O. Box 1331, Piscataway, NJ 08854-1331, http:/www.ieee.org.TABLE 1 Protective Ground Cable, Ferrule, Clamp and Assembly Ratings for Symmetrical CurrentGradeGround

24、ing Clamp TorqueStrength, min Short Circuit PropertiesAContinuousCurrentRating, ARMS, 60HzYieldB UltimateWithstand Rating, SymmetricalkARMS, 60 HzUltimate Rating CapacityCD , SymmetricalkARMS, 60 Hzlbfin. nm lbfin. nm15cycles(250 ms)30 cycles(500ms)Copper CableSize15cycles(250ms)30cycles(500ms)60cyc

25、les(1 s)MaximumCopper TestCable Size1 280 32 330 37 14 10 #2 18 13 9 2/0 2002 280 32 330 37 21 15 1/0 29 21 14 4/0 2503 280 32 330 37 27 20 2/0 37 26 18 4/0 3004 330 37 400 45 34 25 3/0 47 33 23 250 kcmil 3505 330 37 400 45 43 30 4/0 59 42 29 250 kcmil 4006 330 37 400 45 54 39 250 kcmil or2 2/070 49

26、 35 350 kcmil 4507 330 37 400 45 74 54 350 kcmil or2 4/098 69 48 550 kcmil 550A Withstand and ultimate short circuit properties are based on performance with surges not exceeding 20 % asymmetry factor (see 9.1 and 12.3.4.2).B Yield shall mean no permanent deformation such that the clamp cannot be re

27、used throughout its entire range of application.C Ultimate rating represents a symmetrical current which the assembly or individual components shall carry for the specified time.D Ultimate values are based upon application of Onderdonks equation to 98 % of nominal circular mil area allowed by Specif

28、ications B172 and B173.F855 172Throughout this specification, kc mil = 1000 circular mils.3.1.3 protective grounding equipmentdevices installed temporarily on de-energized electric power circuits for the purposes ofpotential equalization and to conduct a short circuit current for a specified duratio

29、n (time).3.1.4 time to failurefailure time of the cable is the time between the initiation of current flow and the instant at which arcingbegins.3.1.5 ultimate capacitythis represents a current which it is calculated the component is capable of conducting for the specifiedtime. It is expected that c

30、omponent damage may result. The component shall not be reused, except in test situations.3.1.6 withstand ratingthis represents a near symmetrical current which shall be conducted without any component beingdamaged sufficiently to prevent being operable and reusable. The protective ground shall be ca

31、pable of passing a second test atthis current after being cooled to ambient temperature.CLAMPS FOR TEMPORARY PROTECTIVE GROUNDS4. Scope4.1 This specification covers clamps used with ferrules and elastomer or thermoplastic covered flexible cable in the manufactureof protective grounds installed tempo

32、rarily for protective grounding of de-energized circuits.5. Classification5.1 Clamps are furnished in, but not limited to, three types according to their function and method of installation, as follows:5.1.1 Type IClamps for installation on de-energized conductors equipped with eyes for installation

33、 with removable hot sticks.5.1.2 Type IIClamps for installation on de-energized conductors having permanently mounted hot sticks.5.1.3 Type IIIClamps for installation on permanently grounded conductors or metal structures with tee handles, and eyes orsquare or hexagon head screw(s), or both.5.1.4 Ot

34、her types of special clamps, such as those for cluster grounds or for underground equipment grounding, may be made,tested, and certified by the manufacturer as meeting the requirements of this specification.5.1.5 Separable insulated connectors used in manufacturing underground equipment grounding as

35、semblies shall meet therequirements of IEEE 386.5.2 Clamps are furnished in grades according to mechanical strengths, short circuit capabilities, and duration of faults, asindicated in Table 1 or Table 2. For Table 1 grade designations, clamp ratings must include maximum use current and indicationwh

36、ether testing was done at Ultimate or Withstand Ratings. The maximum use current listed shall not exceed the test current usedin their electrical short circuit design tests (per 12.3.4).5.3 Clamps are furnished in two classes according to the characteristics of the main contact jaws:5.3.1 Class ACla

37、mp jaws with smooth contact surfaces.5.3.2 Class BClamp jaws with serrations, or cross hatching, or other means intended to abrade or bite through corrosionproducts on the surfaces of the conductor being clamped.6. Sizes6.1 Clamp size is the combination of the main contact and cable size ranges as l

38、isted by the manufacturers. It should be notedthat the main contact may connect to a cable or bus bar or be used at the “ground end” to connect to a variety of conductivegrounded objects.7. Ordering Information7.1 Orders for clamps under this specification shall include this ASTM designation and the

39、 following information:7.1.1 Quantity,7.1.2 Name (grounding clamp),7.1.3 Main contact size ranges, conductor descriptions, and materials which are to be clamped by main contact,7.1.4 Cable size, material, and description by which clamps are to be assembled,7.1.5 Type (see 5.1),7.1.6 Grade (see 5.2 a

40、nd Table 1 or Table 2),7.1.7 Class (see 5.3),7.1.8 Asymmetrical current or other supplementary requirements, if applicable. (See Supplementary Requirements S1 to S10for styles and designs.)NOTE 2A typical ordering description is as follows: 100 Grounding Clamps, Main contact range #2 to 350 kcmil fo

41、r 2/0 Copper flexible groundingcable, ASTM F855, Type 1, Grade 3, Class A, Design C, Style 7.NOTE 3It is expected that manufacturers will publish catalog data conforming to this specification that will combine the requirements of 7.1.1 7.1.8NOTE 1TPG testing is done on complete assemblies. Assembly

42、ratings assume the grade of lowest graded component (see 43.1.6).F855 173TABLE 2 Ultimate Assembly Rating for High X/R Ratio ApplicationsGradeSizeRatingRatedCurrent(kA)High Asymmetrical Test RequirementsX/R = 30Cycle Current PeakValues (kA)Rating X 2.69TestDuration(cycles)12t(Mega amps2-s)1st 2nd 3r

43、d 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th1H 15 41 37 34 32 30 28 27 26 25 25 24 24 23 23 23 15 742H 25 68 62 57 53 50 47 45 43 42 41 40 39 38 38 38 15 2083H 31 84 76 70 65 61 58 56 53 52 50 49 48 47 47 46 15 3124H 39 105 96 88 82 77 73 70 67 65 63 62 61 60 59 58 15 5015H 47 127 116 106

44、 99 93 88 84 81 78 76 74 73 72 71 70 15 7286H 55 148 135 124 116 109 103 98 94 91 89 87 85 84 83 82 15 9977H 68 183 167 154 143 134 127 121 117 113 110 107 105 104 102 101 15 1523F855174NOTE 1The above current values are based on electromechanical test values.F855175NOTE 2Assemblies that have been s

45、ubjected to these shall not be re-used.F855176NOTE 3For use with currents exceeding 20 % asymmetry factor.F855177NOTE 4See X4.7.2X2.7.2 for additional information.F855178NOTE 5Alternate testing circuits are available for laboratories that cannot achieve the above requirements. See Appendix X4X2 for

46、details.F855179in a single product number. With that system, a typical order description is: 100 (Smith Manufacturing Co. Product No. XXXX) grounding clampsASTMF855, Grade 2-max use 21kA, Ultimate Rating.8. Materials8.1 Current carrying parts made of copper base or aluminum base alloy shall have the

47、 following material properties inaccordance with Test Methods E8/E8M:Copper Base Alloy Aluminum Base AlloyTensile strength, min 207 MPa (30 000 psi) 207 MPa (30 000 psi)Yield strength, min 90 MPa (13 000 psi) 138 MPa (20 000 psi)Elongation, min 6 % 3 %8.2 Type II clamps shall be equipped with an ins

48、ulating handle (hot stick) appropriate for the nominal voltage of the circuit tobe grounded.9. Electrical and Mechanical Properties9.1 Electrical and mechanical properties shall conform to the requirements prescribed in Table 1 or Table 2, as appropriate, andthe following paragraphs. See Appendix X3

49、X1 for a discussion and derivation of the current levels in Table 1. See Appendix X4X2for a discussion of the effects of asymmetrical current and the derivation of the currents in Table 2.9.1.1 Types I and II stick installed clamps shall be designed such that a failure does not increase the risk of injury to the useror have excess mechanical strength to prevent failure, defined as follows:9.1.1.1 In the event the clamp is over-torqued during installation, normal fracture shall be such that the attached cable remainsunder contro