1、Designation: D 1711 02An American National StandardStandard Terminology Relating toElectrical Insulation1This standard is issued under the fixed designation D 1711; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis terminology is used in connection with testing and specifying solid electrical insulatingmaterials. Modifications to t
3、his terminology, reflecting common usage, may appear in particular testmethods, material specifications, practices, or other standards. Included herein are terms pertinent togeneral applications, electrical insulating papers, mica, mica processing, processed mica forms,hookup wire insulation, and pa
4、rtial discharge (corona).1. Scope1.1 This terminology is a compilation of technical termsused in conjunction with testing and specifying solid electricaland electronic insulating materials in standards under thejurisdiction of Committee D09 on Electrical and ElectronicInsulating Materials.1.2 It is
5、intended that all definitions in this terminology areidentical to definitions of the same terms as printed in standardsof originating technical subcommittees, with the exceptions of:(1) deletion of any part of the Discussion included in anotherstandard that refers specifically to the use of a term i
6、n thatstandard; (2) figure numbers and corresponding references; and(3) in this terminology, a parenthetical addition of a referenceto one or more technical standards in which the term is usedand the year in which the term was added to this compilation.1.3 Symbols may be included as part of the repr
7、esentationof terms, where appropriate.1.4 It is not intended that this terminology include descrip-tions of terms or symbols (except as noted in 1.3). Acronymsand abbreviations referring directly to defined terms may beincluded.1.5 Revisions and additions to the definitions in this termi-nology are
8、to be made as a product of a collaborative effortbetween Subcommittee D09.94 and the various technicalsubcommittees of Committee D09, with Subcommittee D09.94providing editorial advice to the technical subcommittees. Newdefinitions and revisions of existing definitions must first beapproved by the c
9、ognizant technical subcommittee (or subcom-mittees) before inclusion in this terminology.2. Referenced Documents2.1 ASTM Standards:D 149 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Electrical Insulating Materials atCommercial Power Frequencies2D 150 Test Methods for AC Los
10、s Characteristics and Per-mittivity Dielectric Constant of Solid Electrical Insulation2D 3426 Test Method for Dielectric Breakdown Voltage andDielectric Strength of Solid Electrical Insulating MaterialsUsing Impulse Waves3D 3636 Practice for Sampling and Judging Quality of SolidElectrical Insulating
11、 Materials32.2 Other Standards:ANSI/ASQC A2-198743. Terminologyacceptable quality level (AQL), nthe maximum percentnonconforming which, for purposes of sampling inspection,is considered satisfactory as a process average.acceptance number, nthe maximum allowable number ofnonconformities for a given A
12、QL and sample size (lot-sample size).air chain, nin mica, a series of air inclusions in the form ofa chain or streak.arc propagation, nthe movement of an electric arc from itspoint of inception to another location. (1996) D 3032arc tracking, nthe process producing tracks when arcs occuron or close t
13、o the insulation surface.Arrhenius plot, na graph of the logarithm of thermal life asa function of the reciprocal of absolute temperature.1This terminology is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee
14、 D09.94 on Editorial.Current edition approved March 10, 2002. Published June 2002. Originallypublished as D 1711 60 T. Last previous edition D 1711 99.2Annual Book of ASTM Standards, Vol 10.01.3Annual Book of ASTM Standards, Vol 10.02.4Available from American National Standards Association, 11 W. 42
15、nd St., 13thFloor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.DISCUSSIONThis is normally depicted as the best straight line fit,determined by least squares, of end points obtained at aging tempera-tures. It is
16、 important that the slope, which is the activation energy of thedegradation reaction, be approximately constant within the selectedtemperature range to ensure a valid extrapolation.ash content of paper, nthe solid residue remaining aftercombustion of the paper under specified conditions, ex-pressed
17、as a percentage of the dry mass of the original paper.(1996) D 202average discharge (corona) current (It), nthe sum of theabsolute magnitudes of the individual discharges during acertain time interval divided by that time interval.DISCUSSIONWhen the discharges are measured in coulombs and thetime in
18、terval in seconds, the calculated current will be in amperes.It5(t0t1Q11 Q21222222Qnt12 t0(1)where:It= average current, A,t0= starting time, s,t1= completion time, s, andQ1,Q2,Qn= partial discharge quantity in a corona pulse1 through n,C.binder tapesee core wrap (binder tape).bond strength, na measu
19、re of the force required to separatesurfaces which have been bonded together. (1996)D 2519, D 3145, D 4882braid, n(1) woven metallic wire used as a shield forinsulated conductors and cables.(2) A woven fibrous protective outer covering over aninsulated conductor or cable.breakdown voltagesee dielect
20、ric breakdown voltage.bursting strength of paper, nthe hydrostatic pressure re-quired to produce rupture of a circular area of the materialunder specified test conditions. (1996) D 202cable wrap, npaper used for mechanical protection or forspace-filling (rather than as electrical insulation) in low-
21、voltage cables with nonmetallic sheaths.capacitance, C, nthat property of a system of conductorsand dielectrics which permits the storage of electricallyseparated charges when potential differences exist betweenthe conductors.DISCUSSIONCapacitance is the ratio of a quantity, q, of electricity toa po
22、tential difference, V. A capacitance value is always positive. Theunits are farads when the charge is expressed in coulombs and thepotential in volts:C 5 q/V (2)capacitor tissue, nvery thin (5 to 50 m) pure, nonporouspaper used as the dielectric in capacitors, usually in conjunc-tion with an insulat
23、ing liquid.coating powder, na heat-fusible, finely-divided solid resin-ous material used to form electrical insulating coatings.(1996) D 2967, D 3214concentricity, nthe ratio, expressed in percent, of the mini-mum wall thickness to the maximum wall thickness.concentric-lay conductor, na conductor co
24、mposed of acentral core surrounded by one or more layers of helicallylaid strands.DISCUSSIONIn the most common type of concentric-lay conductor,all strands are of the same size and the central core is a single strand.conductance, insulation, nthe ratio of the total volume andsurface current between
25、two electrodes (on or in a specimen)to the dc voltage applied to the two electrodes.DISCUSSIONInsulation conductance is the reciprocal of insulationresistance.conductance, surface, nthe ratio of the current between twoelectrodes (on the surface of a specimen) to the dc voltageapplied to the electrod
26、es.DISCUSSION(Some volume conductance is unavoidably included inthe actual measurement.) Surface conductance is the reciprocal ofsurface resistance.conductance, volume, nthe ratio of the current in thevolume of a specimen between two electrodes (on or in thespecimen) to the dc voltage applied to the
27、 two electrodes.DISCUSSIONVolume conductance is the reciprocal of volume resis-tance.conducting material (conductor), na material within whichan electric current is produced by application of a voltagebetween points on, or within, the material.DISCUSSIONThe term “conducting material” is usually appl
28、ied onlyto those materials in which a relatively small potential difference resultsin a relatively large current since all materials appear to permit someconduction current. Metals and strong electrolytes are examples ofconducting materials.conductivity, surface, nthe surface conductance multipliedb
29、y that ratio of specimen surface dimensions (distancebetween electrodes divided by the width of electrodesdefining the current path) which transforms the measuredconductance to that obtained if the electrodes had formed theopposite sides of a square.DISCUSSIONSurface conductivity is expressed in sie
30、mens. It ispopularly expressed as siemens/square (the size of the square isimmaterial). Surface conductivity is the reciprocal of surface resistivity.conductivity, volume, nthe volume conductance multipliedby that ratio of specimen volume dimensions (distancebetween electrodes divided by the cross-s
31、ectional area of theelectrodes) which transforms the measured conductance tothat conductance obtained if the electrodes had formed theopposite sides of a unit cube.DISCUSSIONVolume conductivity is usually expressed in siemens/centimetre or in siemens/metre and is the reciprocal of volumeresistivity.
32、conductor, na wire, or combination of wires not insulatedfrom each other, suitable for carrying electric current. (1996)D 1676continuous partial discharges (continuous corona),ndischarges that recur at rather regular intervals; forexample on approximately every cycle of an alternatingD 17112voltage
33、or at least once per minute for an applied directvoltage.core wrap (binder tape), npaper used to wrap groups ofinsulated wire into cable configuration prior to sheathing.DISCUSSIONUsually, this term is applied to telephone communica-tion cables in which core wrap is not regularly subjected to voltag
34、estress, but may be exposed to surges from lightning strokes or otheraccidental events.corona, nvisible partial discharges in gases adjacent to aconductor.DISCUSSIONThis term has also been used to refer to partialdischarges in general.critical property, na quantitatively measurable characteris-tic w
35、hich is absolutely necessary to be met if a material orproduct is to provide satisfactory performance for theintended use.DISCUSSIONIn some situations, specification requirements coincidewith customer usage requirements. In other situations, they may notcoincide, being either more or less stringent.
36、 More stringent sampling(for example, smaller AQL values) is usually used for measurement ofcharacteristics which are considered critical. The selection of samplingplans is independent of whether the term defect or nonconformity isappropriate.cross grains or reeves, nin mica, tangled laminationscaus
37、ing imperfect cleavage.crude micamica as mined; crude crystals with dirt and rockadhering.crystallographic discoloration, nin mica, discoloration ap-pearing as bands of lighter or darker shades of basic color ofa block of mica. (1996)DISCUSSIONSuch bands are generally parallel to the crystallo-graph
38、ic faces of the crystal from which the block was separated.defect, na departure of a quality characteristic from itsintended level, or state, that occurs with a severity sufficientto cause an associated product or service not to satisfyintended normal, or reasonably foreseeable, usage require-ments.
39、DISCUSSIONThe terms “defect” and “nonconformity” and theirderivatives are used somewhat interchangeably in the historical andcurrent literature. Nonconformity objectively describes the comparisonof test results to specification requirements, while the term defect has aconnotation of predicting the f
40、ailure of a product or service to performits intended function in use. Since this latter connotation is oftenunintended, the term nonconformity is preferred in full consensusstandards. The selection of any sample plan is independent of whetherthe term defect or nonconformity is appropriate.The term
41、defect may be appropriate for specifications mutuallyagreed upon by a producer and a user where specific use conditions areclearly understood. Even in these cases however, use the term defectwith caution and consider substituting the term nonconformity.For additional comments, see ANSI/ASQC A2-1987
42、that also states:“When a quality characteristic of a product or service is “evaluated” interms of conformance to specification requirements, the use of the termnonconformity is appropriate.”dielectric, na medium in which it is possible to maintain anelectric field with little supply of energy from o
43、utsidesources.DISCUSSIONThe energy required to produce the electric field isrecoverable, in whole or in part. A vacuum, as well as any insulatingmaterial, is a dielectric.dielectric breakdown voltage (electric breakdown voltage),nthe potential difference at which dielectric failure occursunder presc
44、ribed conditions, in an electrical insulating ma-terial located between two electrodes. (See also Test MethodD 149, Appendix X1.)DISCUSSIONThe term dielectric breakdown voltage is sometimesshortened to “breakdown voltage.”dielectric constantsee relative permittivity.dielectric failure (under test),
45、nan event that is evidencedby an increase in conductance in the dielectric under testlimiting the electric field that can be sustained.dielectric strength, nthe voltage gradient at which dielectricfailure of the insulating material occurs under specificconditions of test.dip encapsulation (a type of
46、 conformal coating), nanembedding process in which the insulating material isapplied by immersion and without the use of an outercontainer.DISCUSSIONThe coating so formed generally conforms with thecontour of the embedded part.dissipation factor (loss tangent) (tan d), D, nthe ratio ofthe loss index
47、 to its relative permittivity orD 5k9/k8 (3)It is also the tangent of its loss angle, d, or the cotangentof its phase angle, u. (See Fig. 1 and Fig. 2.)DISCUSSIONa:D 5 tan d5cot u5Xp/Rp5 G/vCp5 1/vCpRp(4)where:G = equivalent ac conductance,Xp= parallel reactance,Rp= equivalent ac parallel resistance
48、,Cp= parallel capacitance, andv =2pf (sinusoidal wave shape assumed).The reciprocal of the dissipation factor is the quality factor, Q,sometimes called the storage factor. The dissipation factor, D,ofthecapacitor is the same for both the series and parallel representations asfollows:D 5vRsCs5 1/vRpC
49、p(5)The relationships between series and parallel components are as follows:FIG. 1 Vector Diagram for Parallel CircuitD 17113Cp5 Cs/1 1 D2! (6)Rp/Rs5 1 1 D2!/D25 1 1 1/D2! 5 l 1 Q2DISCUSSIONb: Series RepresentationWhile the parallel represen-tation of an insulating material having a dielectric loss (Fig. 3) isusually the proper representation, it is always possible and occasionallydesirable to represent a capacitor at a single frequency by a capacitance,Cs, in series with a resistance, Rs(Fig. 4 and Fig. 2).drainage, no
