1、Designation: F855 15Standard Specifications forTemporary Protective Grounds to Be Used on De-energizedElectric Power Lines and Equipment1This standard is issued under the fixed designation F855; the number immediately following the designation indicates the year of originaladoption or, in the case o
2、f 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 thetemporary grounding system used on de-energi
3、zed electricpower lines, electric supply stations, and equipment.1.2 It is common practice for the users of protectivegrounding equipment to prepare complete instructions andregulations to govern in detail the correct use and maintenanceof such equipment.1.3 The uses and maintenance of this equipmen
4、t are beyondthe scope of these specifications.1.4 These specifications for a system of protective ground-ing utilizing copper cables are covered in four parts, as follows:SectionsClamps for Temporary Protective Grounds 416Ferrules for Temporary Protective Grounds 1730Cables for Temporary Protective
5、Grounds 3139Protective Grounds (Complete Assembly With Clamps, Ferrules,and Cable)40521.5 Each of the four parts is an entity of itself, but is listedas a part of the system for completeness and clarification.1.6 Currents presented in Table 1 are based upon cablemelting times, as determined from equ
6、ations by I. M. Onder-donk and are to used in situations involving an asymmetryvalue less than 20 % (X/R 1.8). See Appendix X3.1.6.1 Currents presented in Table 2 are based upon thevalues from EPRI Project RP2446 Computer Program RTGC“A Desktop Computer Program for Calculating Rating ofTemporary Gro
7、unding Cables” and are to be used in situationsinvolving an asymmetry value greater then 20 % (X/R 1.8),see Appendix X4.NOTE 1Table 1 represents the clamp and assembly ratings that existedprior to this revision. Table 2 represents new ratings now required for highX/R situations.1.6.2 See Appendix X3
8、 and Appendix X4 for a discussionof these topics.1.7 The values stated in Newton-Meter units are to beregarded as the standard. The values in parentheses are theinch-pound units.1.8 The following precautionary caveat pertains to the testmethod portions, Sections 12 and 25 of these specifications:Thi
9、s standard does not purport to address all of the safetyconcerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1
10、 ASTM Standards:2B172 Specification for Rope-Lay-Stranded Copper Conduc-tors Having Bunch-Stranded Members, for Electrical Con-ductorsB173 Specification for Rope-Lay-Stranded Copper Conduc-tors Having Concentric-Stranded Members, for ElectricalConductorsD470 Test Methods for Crosslinked Insulations
11、and Jacketsfor Wire and CableD753 Specification for General Purpose PolychloropreneJacket for Wire and Cable (Withdrawn 1984)3D2219 Specification for Poly(Vinyl Chloride) Insulation forWire and Cable, 60C OperationD2633 Test Methods for Thermoplastic Insulations andJackets for Wire and CableD2768 Sp
12、ecification for General-Purpose Ethylene-Propylene Rubber Jacket for Wire and Cable (Withdrawn2007)3D2770 Specification for Ozone-Resisting Ethylene-Propylene Rubber Integral Insulation and Jacket for Wireand Cable (Withdrawn 2007)3E8/E8M Test Methods for Tension Testing of Metallic Ma-terials1These
13、 specifications are under the jurisdiction of ASTM Committee F18 onElectrical Protective Equipment for Workers and are the direct responsibility ofSubcommittee F18.45 on Mechanical Apparatus.Current edition approved June 1, 2015. Published July 2015. Originally approvedin 1983. Last previous edition
14、 approved in 2014 as F855 14. DOI: 10.1520/F0855-15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last
15、 approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ANSI Standard:4C 37.09 Standard Test Procedure for AC High-VoltageCircuit Breakers Rated on a Symmetrical B
16、asis2.3 ICEA/NEMA Standard:5ICEA S-19-81/NEMA WC 3-80 (R 1986) Rubber InsulatedWire and Cable for the Transmission and Distribution ofElectrical Energy2.4 IEC Standard:6IEC 61230 Ed. 2, 2008, Portable Equipment for Earthing orEarthing and Short-Circuiting2.5 IEEE Standard:7IEEE 386 Standard for Sepa
17、rable Insulated Connector Sys-tems for Power Distribution Systems Above 600VIEEE 1048 Guide for Protective Grounding of Power LinesIEEE 1246 Guide for Temporary Protective Grounding Sys-tems Used in Substations3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 continuous current
18、ratingdesignated RMS currentwhich can be carried continuously under specified conditions.3.1.2 protective ground assemblya temporary electricalconnection between a source of potential energization and theearth, rated for the maximum anticipated fault current orcontinuous induced current, or both.3.1
19、.2.1 DiscussionThroughout this specification, kcmil = 1000 circular mils.3.1.3 protective grounding equipmentdevices installedtemporarily on de-energized electric power circuits for thepurposes of potential equalization and to conduct a short circuitcurrent for a specified duration (time).3.1.4 time
20、 to failurefailure time of the cable is the timebetween the initiation of current flow and the instant at whicharcing begins.3.1.5 ultimate capacitythis represents a current which it iscalculated the component is capable of conducting for thespecified time. It is expected that component damage mayre
21、sult. The component shall not be reused, except in testsituations.3.1.6 withstand ratingthis represents a near symmetricalcurrent which shall be conducted without any component beingdamaged sufficiently to prevent being operable and reusable.The protective ground shall be capable of passing a second
22、 testat this current after being cooled to ambient temperature.CLAMPS FOR TEMPORARY PROTECTIVEGROUNDS4. Scope4.1 This specification covers clamps used with ferrules andelastomer or thermoplastic covered flexible cable in the manu-facture of protective grounds installed temporarily for protec-tive gr
23、ounding of de-energized circuits.5. Classification5.1 Clamps are furnished in, but not limited to, three typesaccording to their function and method of installation, asfollows:5.1.1 Type IClamps for installation on de-energized con-ductors equipped with eyes for installation with removable hotsticks
24、.5.1.2 Type IIClamps for installation on de-energized con-ductors having permanently mounted hot sticks.4Available from American National Standards Institute, 11 West 42nd St., 13thFloor, New York, NY 10036.5Available from Insulated Cable EngineersAssoc., P.O. Box P, South Yarmouth,MA 02664.6Availab
25、le from International Electrotechnical Commission (IEC), 3 rue deVaremb, Case postale 131, CH-1211, Geneva 20, Switzerland, http:/www.iec.ch.7Available 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
26、 1 Protective Ground Cable, Ferrule, Clamp and Assembly Ratings for Symmetrical CurrentGradeGrounding Clamp TorqueStrength, minShort Circuit PropertiesAContinuousCurrentRating, ARMS, 60HzYieldBUltimateWithstand Rating, SymmetricalkARMS, 60 HzUltimate Rating CapacityCD, SymmetricalkARMS, 60 Hzlbfin.
27、nm lbfin. nm15cycles(250 ms)30 cycles(500ms)Copper CableSize15cycles(250ms)30cycles(500ms)60cycles(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
28、3505 330 37 400 45 43 30 4/0 59 42 29 250 kcmil 4006 330 37 400 45 54 39 250 kcmil or22/070 49 35 350 kcmil 4507 330 37 400 45 74 54 350 kcmil or24/098 69 48 550 kcmil 550AWithstand and ultimate short circuit properties are based on performance with surges not exceeding 20 % asymmetry factor (see 9.
29、1 and 12.3.4.2).BYield shall mean no permanent deformation such that the clamp cannot be reused throughout its entire range of application.CUltimate rating represents a symmetrical current which the assembly or individual components shall carry for the specified time.DUltimate values are based upon
30、application of Onderdonks equation to 98 % of nominal circular mil area allowed by Specifications B172 and B173.NOTE 1TPG testing is done on complete assemblies. Assembly ratings assume the grade of lowest graded component (see 43.1.6).F855 152TABLE2UltimateAssemblyRatingforHighX/RRatioApplicationsG
31、radeSizeRating RatedCurrent(kA)HighAsymmetricalTestRequirementsX/R=30CycleCurrentPeakValues(kA)RatingX2.69TestDuration(cycles)12t(Megaamps2-s)1st2nd3rd4th5th6th7th8th9th10th11th12th13th14th15th1H1541373432302827262525242423232315742H25686257535047454342414039383838152083H3184767065615856535250494847
32、4746153124H391059688827773706765636261605958155015H47127116106999388848178767473727170157286H55148135124116109103989491898785848382159977H68183167154143134127121117113110107105104102101151523NOTE1Theabovecurrentvaluesarebasedonelectromechanicaltestvalues.NOTE2Assembliesthathavebeensubjectedtothesesh
33、allnotbere-used.NOTE3Forusewithcurrentsexceeding20%asymmetryfactor.NOTE4SeeX4.7.2foradditionalinformation.NOTE5Alternatetestingcircuitsareavailableforlaboratoriesthatcannotachievetheaboverequirements.SeeAppendixX4fordetails.F855 1535.1.3 Type IIIClamps for installation on permanentlygrounded conduct
34、ors or metal structures with tee handles, andeyes or square or hexagon head screw(s), or both.5.1.4 Other types of special clamps, such as those for clustergrounds or for underground equipment grounding, may bemade, tested, and certified by the manufacturer as meeting therequirements of this specifi
35、cation.5.1.5 Separable insulated connectors used in manufacturingunderground equipment grounding assemblies shall meet therequirements of IEEE 386.5.2 Clamps are furnished in grades according to mechanicalstrengths, short circuit capabilities, and duration of faults, asindicated in Table 1 or Table
36、2. For Table 1 grade designations,clamp ratings must include maximum use current and indica-tion whether testing was done at Ultimate or WithstandRatings. The maximum use current listed shall not exceed thetest current used in their electrical short circuit design tests (per12.3.4).5.3 Clamps are fu
37、rnished in two classes according to thecharacteristics of the main contact jaws:5.3.1 Class AClamp jaws with smooth contact surfaces.5.3.2 Class BClamp jaws with serrations, or crosshatching, or other means intended to abrade or bite throughcorrosion products on the surfaces of the conductor beingcl
38、amped.6. Sizes6.1 Clamp size is the combination of the main contact andcable size ranges as listed by the manufacturers. It should benoted that the main contact may connect to a cable or bus baror be used at the “ground end” to connect to a variety ofconductive grounded objects.7. Ordering Informati
39、on7.1 Orders for clamps under this specification shall includethis ASTM designation and the following information:7.1.1 Quantity,7.1.2 Name (grounding clamp),7.1.3 Main contact size ranges, conductor descriptions, andmaterials which are to be clamped by main contact,7.1.4 Cable size, material, and d
40、escription by which clampsare to be assembled,7.1.5 Type (see 5.1),7.1.6 Grade (see 5.2 and Table 1 or Table 2),7.1.7 Class (see 5.3),7.1.8 Asymmetrical current or other supplementaryrequirements, if applicable. (See Supplementary RequirementsS1 to S10 for styles and designs.)NOTE 2A typical orderin
41、g description is as follows: 100 GroundingClamps, Main contact range #2 to 350 kcmil for 2/0 Copper flexiblegrounding cable, ASTM F855, Type 1, Grade 3, Class A, Design C, Style7.NOTE 3It is expected that manufacturers will publish catalog dataconforming to this specification that will combine the r
42、equirements of7.1.1 7.1.8 in a single product number. With that system, a typical orderdescription is: 100 (Smith Manufacturing Co. Product No. XXXX)grounding clamps ASTM F855, Grade 2-max use 21kA, Ultimate Rating.8. Materials8.1 Current carrying parts made of copper base or aluminumbase alloy shal
43、l have the 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 w
44、ith an insulatinghandle (hot stick) appropriate for the nominal voltage of thecircuit to be grounded.9. Electrical and Mechanical Properties9.1 Electrical and mechanical properties shall conform tothe requirements prescribed in Table 1 or Table 2,asappropriate, and the following paragraphs. See Appe
45、ndix X3for a discussion and derivation of the current levels in Table 1.See Appendix X4 for a discussion of the effects of asymmetri-cal current and the derivation of the currents in Table 2.9.1.1 Types I and II stick installed clamps shall be designedsuch that a failure does not increase the risk o
46、f injury to theuser or have excess mechanical strength to prevent failure,defined as follows:9.1.1.1 In the event the clamp is over-torqued duringinstallation, normal fracture shall be such that the attachedcable remains under control by being retained with the stick.9.1.1.2 Clamps with an ultimate
47、torque strength exceeding45 Nm (400 lbfin.) are exempt from the provisions of 9.1.1.1.9.1.2 Resistance from the main contact to the attached cablecontact shall be less than that for an equal length of maximumsize cable(s) for which the clamp is rated.9.1.3 Main contacts shall accept and clamp all co
48、nductors orstructural members in accordance with the manufacturersrating.9.1.4 Clamp shall accept hand assembly of all cables fittedwith compatible ferrules as rated per Table 3.9.1.5 Cable termination shall include a cable support orshall be made to accept a cable supporting ferrule. This supportsh
49、all secure the entire cable over the jacket and is provided inaddition to the electrical connection to the strand.9.1.6 Type I clamps shall be operable with clamp sticks andshall fit securely inside a nominal 13 mm (12 in.) wide slot inthe head of the stick.10. Workmanship, Finish, and Appearance10.1 Components shall be free of structural porosity, fins,sharp edges, splits, cracks, and other defects that affecthandling or performance.10.2 All parts shall be formed, machined, and assembledwith sufficient accuracy for smooth operation by h
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