D09.12 - Electrical Tests
Electrical Tests
General Information
ABSTRACT
These test methods cover the testing of fibrous-insulated electrical conductors, commonly referred to as magnet wire, which are used in electrical apparatus. The test methods are intended primarily for evaluation of the electrical insulating materials used. It is intended that these test methods be used, except where modified by individual specifications for particular applications. This elongation testing method covers the determination of the elongation of fibrous insulated magnet wire that results in a fracture of the conductor. The electrical resistance testing method covers the determination of the electrical resistance of fibrous insulated magnet wire conductors. The fibrous coverage testing method covers the determination of the quality of fibrous servings on round magnet wire or bare conductor. The measurement of dimensions test methods determine the dimensions of the bare or film insulated conductor and the fibrous-insulated magnet wire. The adhesion and flexibility test method covers the evaluation of the flexibility and adherence of varnished fibrous glass, and varnished or unvarnished fibrous polyester-glass insulating material on either bare conductor, or film-insulated magnet wire. The dielectric breakdown voltage test method covers the determination of the dielectric breakdown voltage in air of insulation on round, rectangular, and square wires at commercial power frequencies.
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1.1 These test methods cover the testing of fibrous-insulated electrical conductors, commonly referred to as magnet wire, which are used in electrical apparatus. The test methods are intended primarily for evaluation of the electrical insulating materials used. It is intended that these test methods be used, except where modified by individual specifications for particular applications.
1.1.1 These test methods apply to those magnet wires that are fiber-covered and in which the substrate is bare conductor or is coated with an underlying insulating film as covered by Test Methods D1676. Fiber-covered wires are produced by serving helically or wrapping fibers or fibrous-tape insulation uniformly around the wire in single and multiple layers. The served or wrapped materials are bonded or not bonded to the underlying wire.
1.2 The test methods appear in the following sections:
Procedure
Section
Measurement of Dimensions
7
Electrical Resistance of Conductors
5
Elongation
4
Adhesion and Flexibility
8
Fibrous Coverage
6
Dielectric Breakdown Voltage
9
1.3 This standard and IEC 60851 are similar if not equivalent in technical content.
1.4 This standard and NEMA MW 1000 are similar if not equivalent in technical content.
1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See 8.4.1 and 9.4.1 for specific caution statements.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Some electrical properties, such as dielectric strength, vary with the thickness of the material. Determination of certain properties, such as relative permittivity (dielectric constant) and volume resistivity, usually require a knowledge of the thickness. Design and construction of electrical machinery require that the thickness of insulation be known.
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1.1 These test methods cover the determination of the thickness of several types of solid electrical insulating materials employing recommended techniques. Use these test methods except as otherwise required by a material specification.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard12 pagesEnglish language
- Standard12 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Permittivity—Insulating materials are used in general in two distinct ways, (1) to support and insulate components of an electrical network from each other and from ground, and (2) to function as the dielectric of a capacitor. For the first use, it is generally desirable to have the capacitance of the support as small as possible, consistent with acceptable mechanical, chemical, and heat-resisting properties. A low value of permittivity is thus desirable. For the second use, it is desirable to have a high value of permittivity, so that the capacitor is able to be physically as small as possible. Intermediate values of permittivity are sometimes used for grading stresses at the edge or end of a conductor to minimize ac corona. Factors affecting permittivity are discussed in Appendix X3.
5.2 AC Loss—For both cases (as electrical insulation and as capacitor dielectric) the ac loss generally needs to be small, both in order to reduce the heating of the material and to minimize its effect on the rest of the network. In high frequency applications, a low value of loss index is particularly desirable, since for a given value of loss index, the dielectric loss increases directly with frequency. In certain dielectric configurations such as are used in terminating bushings and cables for test, an increased loss, usually obtained from increased conductivity, is sometimes introduced to control the voltage gradient. In comparisons of materials having approximately the same permittivity or in the use of any material under such conditions that its permittivity remains essentially constant, it is potentially useful to consider also dissipation factor, power factor, phase angle, or loss angle. Factors affecting ac loss are discussed in Appendix X3.
5.3 Correlation—When adequate correlating data are available, dissipation factor or power factor are useful to indicate the characteristics of a material in other respects such as dielectric breakdown, moisture content, degree o...
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1.1 These test methods cover the determination of relative permittivity, dissipation factor, loss index, power factor, phase angle, and loss angle of specimens of solid electrical insulating materials when the standards used are lumped impedances. The frequency range addressed extends from less than 1 Hz to several hundred megahertz.
Note 1: In common usage, the word relative is frequently dropped.
1.2 These test methods provide general information on a variety of electrodes, apparatus, and measurement techniques. A reader interested in issues associated with a specific material needs to consult ASTM standards or other documents directly applicable to the material to be tested.2,3
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see 10.2.1.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard20 pagesEnglish language
- Standard20 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
5.2 Relative complex permittivity (relative complex dielectric constant), , is the proportionality factor that relates the electric field to the electric flux density, and which depends on intrinsic material properties such as molecular polarizability, charge mobility, and so forth:
where:
ε0 = permittivity of free space = electric flux density vector, and = electric field vector.
Note 1: In common usage the word “relative” is frequently dropped. The real part of complex relative permittivity ( ) is often referred to as simply relative permittivity, permittivity, or dielectric constant. The imaginary part of complex relative permittivity ( ) is often referred to as the loss factor. In anisotropic media, permittivity is described by a three dimensional tensor.
Note 2: For the purposes of this test method, the media is considered to be isotropic and, therefore, permittivity is a single complex number at each frequency.
5.3 Relative complex permeability, , is the proportionality factor that relates the magnetic flux density to the magnetic field, and which depends on intrinsic material properties such as magnetic moment, domain magnetization, and so forth:
where:
μ0 = permeability of free space, = magnetic flux density vector, and = magnetic field vector.
Note 3: In common usage the word “relative” is frequently dropped. The real part of complex relative permeability ( ) is often referred to as relative perme...
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1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 1 GHz to over 20 GHz. These limits are not exact and depend on the size of the specimen, the size of coaxial air line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. For a given air line size, the upper frequency is also limited by the onset of higher order modes that invalidate the dominant-mode transmission line model and the lower frequency is limited by the smallest measurable phase shift through a specimen. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. The coaxial fixture is preferred over rectangular waveguide fixtures when broadband data are desired with a single sample or when only small sample volumes are available, particularly for lower frequency measurements.
1.3 The values stated in either SI units of in inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore each system shall be used independently of the other. Combining values from the two systems is likely to result in non conformance with the standard. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to ...
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
5.2 Relative complex permittivity (relative complex dielectric constant), εr*, is the proportionality factor that relates the electric field to the electric flux density, and which depends on intrinsic material properties such as molecular polarizability, charge mobility, and so forth:
where:
ε0 = the permittivity of free space, D→ = the electric flux density vector, and E→ = the electric field vector.
Note 1: In common usage the word “relative” is frequently dropped. The real part of complex relative permittivity (εr′) is often referred to as simply relative permittivity, permittivity, or dielectric constant. The imaginary part of complex relative permittivity (εr′′) is often referred to as the loss factor. In anisotropic media, permittivity is described by a three dimensional tensor.
Note 2: For the purposes of this test method, the media is considered to be isotropic and, therefore, permittivity is a single complex number at each frequency.
5.3 Relative complex permeability, μr*, is the proportionality factor that relates the magnetic flux density to the magnetic field, and which depends on intrinsic material properties such as magnetic moment, domain magnetization, and so forth:
where:
μ0 = the permeability of free space, B→ = the magnetic flux density vector, and H→ = the magnetic field vector.
Note 3: In common usage the word “relative” is frequently dropped. The real part of complex relative permeability (μr′) is often referre...
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1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 100 MHz to over 40 GHz. These limits are not exact and depend on the size of the specimen, the size of rectangular waveguide transmission line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. Use of multiple rectangular waveguide transmission line sizes are required to cover this entire frequency range (100 MHz to 40 GHz). This test method can also be generally applied to circular waveguide test fixtures. The rectangular waveguide fixture is preferred over coaxial fixtures when samples have in-plane anisotropy or are difficult to manufacture precisely.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are in inch-pound units and are included for information only. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on sta...
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is useful in research and quality control for evaluating insulating materials and systems since they provide for the measurement of the endurance used to compare different materials to the action of corona on the external surfaces. A poor result on this test does not indicate that the material is a poor selection for use at high voltage or at high voltage stress in the absence of surface corona; surface corona is not the same as corona that occurs in internal cavities. (See Test Methods D3382.)
5.2 This test method is also useful for comparison between materials of the same relative thickness. When agreed upon between the buyer and the seller, it is acceptable to express any differences in terms of relative time to failure or the magnitude of voltage stress (kV/mm or kV/in.) required to produce failure in a specified number of hours.
5.3 It is possible for this test method to also be used to examine the effects of different processing parameters on the same insulating material, such as residual strains produced by quenching, high levels of crystallinity or molding processes that control the concentration and sizes of gas-filled cavities.
5.4 The data are generated in the form of a set of values of lifetimes at a voltage. The dispersion of failure times is analyzed using one of the methods below:
5.4.1 Weibull Probability Plot.
5.4.2 Statistically (see IEEE/IEC 62539-2007 for additional information), to yield an estimate of the central value of the distribution and its standard deviation.
5.4.3 Truncating a test at the time of the fifth failure of a set of nine and using that time as the measure of the central tendency. Two such techniques are described in 10.2.
5.5 This test method intensifies some of the more commonly met conditions of corona attack so that materials are able to be evaluated in a time that is relatively short compared to the life of the equipment. As with most accelerated life tests, caution is necessary in...
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1.1 This test method determines the voltage endurance of solid electrical insulating materials for use at commercial power frequencies under the action of corona (see Note 1). This test method is more meaningful for rating materials with respect to their resistance to prolonged ac stress under corona conditions for comparative evaluation between materials.
Note 1: The term “corona” is used almost exclusively in this test method instead of “partial discharge,” because it is a visible glow at the edge of the electrode interface that is the result of partial discharge. Corona, as defined in Terminology D1711, is “visible partial discharges in gases adjacent to a conductor.”
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 7.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Permittivity and dissipation factor are fundamental design parameters for design of microwave circuitry. Permittivity plays a principal role in determining the wavelength and the impedance of transmission lines. Dissipation factor (along with copper losses) influence attenuation and power losses.
5.2 This test method is suitable for polymeric materials having permittivity in the order of two to eleven. Such materials are popular in applications of stripline and microstrip configurations used in the 1 GHz to 18 GHz range.
5.3 This test method is suitable for design, development, acceptance specifications, and manufacturing quality control.
Note 2: See Appendix X1 for additional information regarding significance of this test method and the application of the results.
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1.1 This test method permits the rapid measurement of apparent relative permittivity and loss tangent (dissipation factor) of metal-clad polymer-based circuit substrates in the X-band (8 GHz to 12.4 GHz).
1.2 This test method is suitable for testing PTFE (polytetrafluorethylene) impregnated glass cloth or random-oriented fiber mats, glass fiber-reinforced polystyrene, polyphenyleneoxide, irradiated polyethylene, and similar materials having a nominal specimen thickness of 1/16 in. (1.6 mm). The materials listed in the preceding sentence have been used in commercial applications at nominal frequency of 9.6 GHz.
Note 1: See Appendix X1 for additional information about range of permittivity, thickness other than 1/16 in. (1.6 mm), and tests at frequencies other than 9.6 GHz.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard13 pagesEnglish language
- Standard13 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The high-voltage, low-current type of arc resistance test is intended to simulate only approximately such service
conditions as exist in alternating current circuits operating at high voltage, but at currents limited to units and tens of milliamperes.
4.2 In order to distinguish more easily among materials that have low arc resistance, the early stages of this test method are mild, and the later stages are successively more severe. The arc occurs intermittently between two electrodes resting on the surface of the specimen, in normal or inverted orientation. The severity is increased in the early stages by successively decreasing to zero the interval between flashes of uniform duration, and in later stages by increasing the current.
4.3 Four general types of failure have been observed:
4.3.1 Many inorganic dielectrics become incandescent, whereupon they are capable of conducting the current. Upon cooling, however, they return to their earlier insulating condition.
4.3.2 Some organic compounds burst into flame without the formation of a visible conducting path in the substance.
4.3.3 Others are seen to fail by “tracking,” that is, a thin wiry line is formed between the electrodes.
4.3.4 The fourth type occurs by carbonization of the surface until sufficient carbon is present to carry the current.
4.4 Materials often fail within the first few seconds after a change in the severity stage. When comparing the arc resistance of materials, much more weight shall be given to a few seconds that overlap two stages than to the same elapsed time within a stage. Thus, there is a much greater difference in arc resistance between 178 and 182 s than between 174 and 178 s.
Note 4: Some investigators have reported attempts to characterize the remaining insulating value of the damaged area after failure by allowing the specimen to cool to room temperature, without disturbance of the original position of the electrodes, and then either (1) measuring the insu...
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1.1 This test method covers, in a preliminary fashion, the differentiation of similar materials’ resistance to the action of a high-voltage, low-current arc close to the surface of insulation, when a conducting path is formed causing the material to become conducting due to the localized thermal and chemical decomposition and erosion.
1.2 The usefulness of this test method is very severely limited by many restrictions and qualifications, some of which are described in the following paragraphs and in Section 5. Generally, this test method shall not be used in material specifications. Whenever possible, alternative test methods shall be used, and their development is encouraged.
1.3 This test method will not, in general, permit conclusions to be drawn concerning the relative arc resistance rankings of materials that are potentially subjected to other types of arcs: for example, high voltage at high currents, and low voltage at low or high currents (promoted by surges or by conducting contaminants).
1.4 The test method is intended, because of its convenience and the short time required for testing, for preliminary screening of material, for detecting the effects of changes in formulation, and for quality control testing after correlation has been established with other types of simulated service arc tests and field experience. Because this test method is usually conducted under clean and dry laboratory conditions rarely encountered in practice, it is possible that the prediction of a material's relative performance in typical applications and in varying “clean to dirty” environments will be substantially altered (Note 1). Caution is urged against drawing strong conclusions without corroborating support of simulated service tests and field testing. Rather, this test method is useful for preliminary evaluation of changes in structure and composition without the complicating influence of environmental conditions, espe...
- Standard11 pagesEnglish language
- Standard11 pagesEnglish language
SIGNIFICANCE AND USE
5.1 These test methods are useful in research and quality control for evaluating insulating materials and systems since they provide for the measurement of charge transfer and energy loss due to partial discharges(4) (5) (6).
5.2 Pulse measurements of partial discharges indicate the magnitude of individual discharges. However, if there are numerous discharges per cycle it is occasionally important to know their charge sum, since this sum is related to the total volume of internal gas spaces that are discharging, if it is assumed that the gas cavities are simple capacitances in series with the capacitances of the solid dielectrics (7) (8).
5.3 Internal (cavity-type) discharges are mainly of the pulse (spark-type) with rapid rise times or the pseudoglow-type with long rise times, depending upon the discharge governing parameters existing within the cavity. If the rise times of the pseudoglow discharges are too long , they will evade detection by pulse detectors as covered in Test Method D1868. However, both the pseudoglow discharges irrespective of the length of their rise time as well as pulseless glow are readily measured either by Method A or B of Test Methods D3382.
5.4 Pseudoglow discharges have been observed to occur in air, particularly when a partially conducting surface is involved. It is possible that such partially conducting surfaces will develop with polymers that are exposed to partial discharges for sufficiently long periods to accumulate acidic degradation products. Also in some applications, like turbogenerators, where a low molecular weight gas such as hydrogen is used as a coolant, it is possible that pseudoglow discharges will develop.
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1.1 These test methods cover two bridge techniques for measuring the energy and integrated charge of pulse and pseudoglow partial discharges:
1.2 Test Method A makes use of capacitance and loss characteristics such as measured by the transformer ratio-arm bridge or the high-voltage Schering bridge (Test Methods D150). Test Method A has been found useful to obtain the integrated charge transfer and energy loss due to partial discharges in a dielectric from the measured increase in capacitance and tan δ with voltage. (See also IEEE 286 and IEEE 1434)
1.3 Test Method B makes use of a somewhat different bridge circuit, identified as a charge-voltage-trace (parallelogram) technique, which indicates directly on an oscilloscope the integrated charge transfer and the magnitude of the energy loss due to partial discharges.
1.4 Both test methods are intended to supplement the measurement and detection of pulse-type partial discharges as covered by Test Method D1868, by measuring the sum of both pulse and pseudoglow discharges per cycle in terms of their charge and energy.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 7.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Electrical equipment has the potential to fail as a result of electrical tracking of insulating material that is exposed to various contaminating environments and surface conditions. A number of ASTM and other tests have been designed to quantify behavior of materials, especially at relatively high voltages. This method is an accelerated test which, at relatively low test voltages, provides a comparison of the performance of insulating materials under wet and contaminated conditions. The Tracking Index-Copper Electrodes test is not related directly to the suitable operating voltage in service.
5.2 When organic electrical insulating materials are subjected to conduction currents between electrodes on their surfaces, many minute tree-like carbonaceous paths or tracks are developed near the electrodes. These tracks are oriented randomly, but generally propagate between the electrodes under the influence of the applied potential difference. Eventually a series of tracks spans the electrode gap, and failure occurs by shorting of the electrodes.
5.3 As in other tracking test methods, for example, IEC 60112 and Test Method D3638, this test method specifies test procedures that are intended to promote the formation of surface discharges which will produce carbon tracks in a reproducible manner. Since these conditions rarely reproduce the actual conditions encountered in service, the results of tracking tests cannot be used to infer either direct or relative service behavior of a material in a specific design application. Tracking tests can be used for screening purposes only. Suitability is verified through testing of the material in actual end use or under conditions that closely simulate actual end use.
5.4 The use of copper electrodes in this type of test was developed at the University of Cincinnati, NEMA laboratory. It is felt by the members of the Industrial Laminates Section of NEMA that using copper electrodes gives a more realistic value for a tracking...
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1.1 This test method was developed using copper electrodes to evaluate the low-voltage (up to 600 V) tracking resistance of materials in the presence of aqueous contaminants.2
Note 1: At this time, only industrial laminates have been examined using this method, which was developed at the National Manufacturers Electrical Association (NEMA) laboratory located at the University of Cincinnati. It was found that a closer end point (less scatter) was obtained than with platinum electrodes, and materials tested tended to be ranked by resin system.
1.1.1 It is acceptable to consider other electrode materials for use with this test method depending upon the application of the insulating material.
1.2 This test method is similar to Test Method D3638, which determines the comparative tracking index of materials using platinum electrodes to produce the tracking on the specimen surface.
1.3 The values stated in metric (SI) units are the standard. The inch-pound equivalents of the metric units are approximate.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard5 pagesEnglish language
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Design calculations for such components as transmission lines, antennas, radomes, resonators, phase shifters, etc., require knowledge of values of complex permittivity at operating frequencies. The related microwave measurements substitute distributed field techniques for low-frequency lumped-circuit impedance techniques.
4.2 Further information on the significance of permittivity is contained in Test Methods D150.
4.3 These test methods are useful for specification acceptance, service evaluation, manufacturing control, and research and development of ceramics, glasses, and organic dielectric materials.
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1.1 These test methods cover the determination of relative (Note 1) complex permittivity (dielectric constant and dissipation factor) of nonmagnetic solid dielectric materials.
Note 1: The word “relative” is often omitted.
1.1.1 Test Method A is for specimens precisely formed to the inside dimension of a waveguide.
1.1.2 Test Method B is for specimens of specified geometry that occupy a very small portion of the space inside a resonant cavity.
1.1.3 Test Method C uses a resonant cavity with fewer restrictions on specimen size, geometry, and placement than Test Methods A and B.
1.2 Although these test methods are used over the microwave frequency spectrum from around 0.5 to 50.0 GHz, each octave increase usually requires a different generator and a smaller test waveguide or resonant cavity.
1.3 Tests at elevated temperatures are made using special high-temperature waveguide and resonant cavities.
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are inch-pound units that are provided for information only and are not considered standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard17 pagesEnglish language
- Standard17 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Insulating materials are used to isolate components of an electrical system from each other and from ground, as well as to provide mechanical support for the components. For this purpose, it is generally desirable to have the insulation resistance as high as possible, consistent with acceptable mechanical, chemical, and heat-resisting properties. Since insulation resistance or conductance combines both volume and surface resistance or conductance, its measured value is most useful when the test specimen and electrodes have the same form as is required in actual use. Surface resistance or conductance changes rapidly with humidity, while volume resistance or conductance changes slowly with the total change being greater in some cases.
5.2 Resistivity or conductivity is used to predict, indirectly, the low-frequency dielectric breakdown and dissipation factor properties of some materials. Resistivity or conductivity is often used as an indirect measure of: moisture content, degree of cure, mechanical continuity, or deterioration of various types. The usefulness of these indirect measurements is dependent on the degree of correlation established by supporting theoretical or experimental investigations. A decrease of surface resistance results either in an increase of the dielectric breakdown voltage because the electric field intensity is reduced, or a decrease of the dielectric breakdown voltage because the area under stress is increased.
5.3 All the dielectric resistances or conductances depend on the length of time of electrification and on the value of applied voltage (in addition to the usual environmental variables). These must be known and reported to make the measured value of resistance or conductance meaningful. Within the electrical insulation materials industry, the adjective “apparent” is generally applied to resistivity values obtained under conditions of arbitrarily selected electrification time. See X1.4.
5.4 Volume resistivity or conductivi...
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1.1 These test methods cover direct-current procedures for the measurement of dc insulation resistance, volume resistance, and surface resistance. From such measurements and the geometric dimensions of specimen and electrodes, both volume and surface resistivity of electrical insulating materials can be calculated, as well as the corresponding conductances and conductivities.
1.2 These test methods are not suitable for use in measuring the electrical resistance/conductance of moderately conductive materials. Use Test Method D4496 to evaluate such materials.
1.3 These test methods describe several general alternative methodologies for measuring resistance (or conductance). Specific materials can be tested most appropriately by using standard ASTM test methods applicable to the specific material that define both voltage stress limits and finite electrification times as well as specimen configuration and electrode geometry. These individual specific test methodologies would be better able to define the precision and bias for the determination.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard18 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Permittivity and dissipation factor are sensitive to changes in chemical composition, impurities, and homogeneity. Measurement of these properties is, therefore, useful for quality control and for determining the effect of environments such as moisture, heat, or radiation.
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1.1 This test method covers the determination of the relative permittivity (dielectric constant) and dissipation factor of solid dielectrics from 50 Hz to 10 MHz over a range of temperatures from −80 to 500 °C.2,3 Two procedures are included as follows:
1.1.1 Procedure A—Using Micrometer Electrode.
1.1.2 Procedure B—Using Precision Capacitor.
Note 1: In common usage the word “relative” is frequently dropped.
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is useful for the comparison of materials, as a quality control test, and for specification purposes.
5.2 This test method is useful in the selection and use of materials in wires, cables, bushings, high-voltage rotating machinery, and other electrical apparatus in which shielding or the distribution of voltage stress is of value.
5.3 Commercially available “moderately conductive” materials frequently are comprised of both conductive and resistive components (that is, cellulose fibers with colloidal carbon black particles attached to portions of the surfaces of those fibers, or discrete conductive particles adhered to the surfaces of electrical insulating polymers). Such commercially available materials are often manufactured in a manner that results in anisotropy of electrical conduction. Hence, the significance of tests using this test method depends upon the orientation of the specimen tested to the direction of the electric field and the relationship between this orientation and the orientation of the material in the electrical apparatus, which uses these materials.
SCOPE
1.1 This test method covers the determination of electrical resistance and electrical resistivity of materials that are generally categorized as moderately conductive and are neither good electrical insulators nor good conductors.
1.2 This test method applies to the materials that exhibit volume resistivity in the range of 100 to 107 Ω-cm or surface resistivity in the range of 103 to 107 Ω (per square).
1.3 This test method is designed for measurements at standard conditions of 23 °C and 50 % relative humidity, but its principles of operation can be applied to specimens measured at lower or higher temperatures and relative humidities.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 8.3.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Electrical equipment can fail as a result of electrical tracking of insulating material that is exposed to various contaminating environments and surface conditions. This method is an accelerated test which at relatively low test voltages, provides a comparison of the performance of insulating materials under wet and contaminated conditions. The comparative tracking index is not related directly to the suitable operating voltage in service.
5.2 When organic electrical insulating materials are subjected to conduction currents between electrodes on their surfaces, many minute tree-like carbonaceous paths or tracks are developed near the electrodes. These tracks are oriented randomly, but generally propagate between the electrodes under the influence of the applied potential difference. Eventually a series of tracks spans the electrode gap, and failure occurs by shorting of the electrodes.
5.3 The conditions specified herein are intended to produce a condition conducive to the formation of surface discharges and possible subsequent tracking. Test conditions are chosen to accelerate a process that is reproducible. Consequently, they rarely reproduce the varied conditions found in actual service. Therefore, while tracking tests serve to differentiate materials under given conditions, results of tracking tests cannot be used to infer either direct or comparative service behavior of an application design. Rather, the results provide a tool for judging the suitability of materials for a given application. The suitability can only be verified through testing the design in actual end use or under conditions which simulate end use as closely as possible.
5.4 The results have been used for insulation coordination of equipment with rated voltage up to 1000 Vac or 1500 Vdc connected to low-voltage supply systems (higher voltages permitted in internal circuits). The complete principles of insulation coordination involve the consideration of the combination of clearanc...
SCOPE
1.1 This test method evaluates in a short period of time the low-voltage (up to 600 V) track resistance or comparative tracking index (CTI) of materials in the presence of aqueous contaminants.
1.2 The values stated in metric (SI) units are to be regarded as standard. The inch-pound equivalents of the metric units are approximate.
1.3 This test method is technically equivalent to the version of IEC Publication 112 cited in 2.2. However, the 2007 version of IEC 60112 Fourth Edition yields numerical CTI values that are very likely to differ significantly from this test method.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
4.1 These tests are useful for specification and control purposes during the manufacture, purchase, and use of the magnet-wire enamels, and for determining uniformity of batches.
SCOPE
1.1 These test methods cover testing liquid enamel coatings used to produce film-insulated magnet wire.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined
1.3 The test methods appear as follows:
Sections
Density
6 – 10
Determined Solids
16 – 22
Effective Solids
31 – 37
Flash Point
11 – 15
Infrared Analysis
45 – 50
Stack Loss
23 – 30
Viscosity
38 – 44
1.4 There is no known IEC equivalent document.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard7 pagesEnglish language
- Standard7 pagesEnglish language
SIGNIFICANCE AND USE
5.1 These test methods differentiate solid electrical insulating materials on the basis of their resistance to the action of voltage stresses along the surface of the solid when wet with an ionizable, electrically conductive liquid contaminant.
5.2 These test methods quantitatively evaluate, in a relative manner, the effects upon an insulating material resulting from the action of electrical discharges upon a material surface. The effects are similar to those that may occur in service under the influence of dirt combined with moisture condensed from the atmosphere.
5.2.1 In the field, the conditions resulting in electrical discharges occur sporadically. Degradation, often in the form of a conducting “track,” develops very slowly until it ultimately bridges the space between conductors thus causing complete electrical breakdown.
5.2.2 In these test methods, the conducting liquid contaminant is continuously supplied at an optimum rate to the surface of a test specimen in such a fashion that essentially continuous electrical discharge can be maintained.
5.2.3 By producing continuous surface discharge with controlled energy it is possible, within a few hours, to cause specimen failure which is similar to failure occurring under long-time exposure to the erratic conditions of service in the field.
5.2.4 The test conditions, which are standardized and accelerated, do not reproduce all of the conditions encountered in service. Use caution when making either direct or comparative service behavior inferences derived from the results of tracking tests.
5.3 The time-to-track a 1-in. (25 mm) distance at a specified voltage between electrodes separated 2 in. (50 mm) has also been found useful in categorizing insulating materials for indoor and protected outdoor applications, such as metal-clad switchgear.
5.4 The initial tracking voltage has been found useful for evaluating insulating materials to be used at high voltages or outdoors and unprotected, as well...
SCOPE
1.1 These test methods cover the evaluation of the relative tracking and erosion resistance of insulating solids using the liquid-contaminant, inclined-plane test.2 The following test methods also can be used to evaluate the tracking resistance of materials: Test Method D2132 (contaminants: dust and fog) and Test Method D3638 (contaminant: conductive liquid drops).
1.2 Two tracking and one erosion test procedure are described:
1.2.1 A “variable voltage method” to evaluate resistance to tracking.
1.2.2 A “time-to-track method” to evaluate resistance to tracking.
1.2.3 A method for quantitative determination of erosion (Annex A1).
1.3 While a particular contaminant solution is specified, other concentrations of the same contaminant, or different contaminants are used to simulate different environmental or service conditions.
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.5 Although this standard and IEC 60587-2007, “Test Methods for Evaluating Resistance to Tracking and Erosion for Electrical Insulating Materials Used Under Severe Ambient Conditions,” differ in approach or detail, data obtained using either are technically equivalent.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 9.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations is...
- Standard12 pagesEnglish language
SIGNIFICANCE AND USE
5.1 The presence of partial discharges (corona) at operating voltage in an insulation system has the potential to result in a significant reduction in the life of the insulating material. Some materials are more susceptible to such discharge damage than others. This characteristic can be investigated using Test Method D2275.
5.2 The presence of partial discharges (corona) in an apparently solid insulation is a potential indication of the existence of internal cavities. Partial discharge tests have been useful in the design and inspection of molded, laminated, and composite insulation, as well as specimens in the form of cables, capacitors, transformers, bushings, stator bars, and rotating machines (1-9), (13), (12). See also AEIC CS5-87, ICEA T-24-380, IEEE 48, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005.
5.3 Partial discharge (corona) inception and extinction voltages are used in the determination of the limiting voltage at which an insulation system will operate free of such discharges. The extinction voltage is often substantially lower than the inception voltage. Where the operating voltage is below the inception voltage but above the extinction voltage, it is possible that a transient over-voltage will initiate discharges which then continue until the voltage is lowered below the extinction voltage. Inception and extinction voltages depend upon many factors, including temperature and the rate at which the voltage is changed. After a time at a voltage, it is possible that discharges will start and stop in a nonuniform and unpredictable fashion, especially for discharges within cavities in certain materials, in particular if the discharge degradation products formed are conductive (1), (5).
5.4 The magnitude (pulse height) of a partial discharge is an indication of the amount of energy that it dissipates in the insulation system. Partial discharge magnitude and pulse rate are useful in estimating the rate, or change of rate, at which deterio...
SCOPE
1.1 This test method covers the detection and measurement of partial discharge (corona) pulses at the terminals of an insulation system under an applied test voltage, including the determination of partial discharge (corona) inception and extinction voltages as the test voltage is raised and lowered. This test method is also useful in determining quantities such as apparent charge and pulse repetition rate together with such integrated quantities as average current, quadratic rate, and power. This test method is useful for test voltages ranging in frequency from zero (direct voltage) to approximately 2000 Hz.
1.2 This test method is directly applicable to a simple insulation system that can be represented as a two-terminal capacitor (1), (2).2
1.3 This test method is also applicable to (distributed parameter) insulation systems such as high-voltage cable. Consideration must be given to attenuation and reflection phenomena in this type of system. Further information on distributed parameter systems of cables, transformers, and rotating machines will be found in Refs (1-9). (See AEIC CS5-87, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005.)
1.4 This test method can be applied to multi-terminal insulation systems, but at some loss in accuracy, especially where the insulation of inductive windings is involved.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Sections 8 and 14.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendation...
- Standard11 pagesEnglish language
- Standard11 pagesEnglish language
SIGNIFICANCE AND USE
5.1 The dielectric strength of an electrical insulating material is a property of interest for any application where an electrical field will be present. In many cases the dielectric strength of a material will be the determining factor in the design of the apparatus in which it is to be used.
5.2 Tests made as specified herein are suitable for use to provide part of the information needed for determining suitability of a material for a given application; and also, for detecting changes or deviations from normal characteristics resulting from processing variables, aging conditions, or other manufacturing or environmental situations. This test method is useful for process control, acceptance or research testing.
5.3 Results obtained by this test method can seldom be used directly to determine the dielectric behavior of a material in an actual application. In most cases it is necessary that these results be evaluated by comparison with results obtained from other functional tests or from tests on other materials, or both, in order to estimate their significance for a particular material.
5.4 Three methods for voltage application are specified in Section 12: Method A, Short-Time Test; Method B, Step-by-Step Test; and Method C, Slow Rate-of-Rise Test. Method A is the most commonly-used test for quality-control tests. However, the longer-time tests, Methods B and C, which usually will give lower test results, will potentially give more meaningful results when different materials are being compared with each other. If a test set with motor-driven voltage control is available, the slow rate-of-rise test is simpler and preferable to the step-by-step test. The results obtained from Methods B and C are comparable to each other.
5.5 Documents specifying the use of this test method shall also specify:
5.5.1 Method of voltage application,
5.5.2 Voltage rate-of-rise, if slow rate-of-rise method is specified,
5.5.3 Specimen selection, preparation, and conditio...
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1.1 This test method covers procedures for the determination of dielectric strength of solid insulating materials at commercial power frequencies, under specified conditions.2,3
1.2 Unless otherwise specified, the tests shall be made at 60 Hz. However, this test method is suitable for use at any frequency from 25 to 800 Hz. At frequencies above 800 Hz, dielectric heating is a potential problem.
1.3 This test method is intended to be used in conjunction with any ASTM standard or other document that refers to this test method. References to this document need to specify the particular options to be used (see 5.5).
1.4 It is suitable for use at various temperatures, and in any suitable gaseous or liquid surrounding medium.
1.5 This test method is not intended for measuring the dielectric strength of materials that are fluid under the conditions of test.
1.6 This test method is not intended for use in determining intrinsic dielectric strength, direct-voltage dielectric strength, or thermal failure under electrical stress (see Test Method D3151).
1.7 This test method is most commonly used to determine the dielectric breakdown voltage through the thickness of a test specimen (puncture). It is also suitable for use to determine dielectric breakdown voltage along the interface between a solid specimen and a gaseous or liquid surrounding medium (flashover). With the addition of instructions modifying Section 12, this test method is also suitable for use for proof testing.
1.8 This test method is similar to IEC Publication 243-1. All procedures in this method are included in IEC 243-1. Differences between this method and IEC 243-1 are largely editorial.
1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicabil...
- Standard13 pagesEnglish language
- Standard13 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is intended for use as a control and acceptance test for direct-voltage applications. It can also be used in the partial evaluation of material for specific end uses and as a means for detecting changes in material due to specific deteriorating causes.
5.2 Experience indicates that the breakdown value obtained with direct voltage usually will be approximately 2 to 4 times the rms value of the 60-Hz alternating-voltage breakdown.
5.3 For a nonhomogeneous test specimen, the distribution of voltage stress within the specimen is determined by impedance (largely capacitive) with alternating voltage. With an increasing direct voltage, the voltage distribution will still be largely capacitive, although this depends partly on the rate of voltage increase. After steady application of direct voltage the voltage division across the test specimen is determined by resistance. The choice of direct or alternating voltage depends upon the purpose for which the breakdown test is to be used, and to some extent, on the intended application of the material.
5.4 A more complete discussion of the significance of dielectric breakdown tests is given in Appendix X1 of this method and in Appendix X1 of Test Method D149. Those appendix sections of Test Method D149 that refer to alternating voltage are not applicable to the direct-voltage method.
SCOPE
1.1 This test method covers the determination of dielectric breakdown voltage and dielectric strength of solid electrical insulating materials under direct-voltage stress.
1.2 Since some materials require special treatment, reference shall also be made to ASTM specifications or to the test method directly applicable to the material to be tested. See Test Method D149 for the determination of dielectric strength of electrical insulating materials at commercial power frequencies.
1.3 This test method is similar to IEC Publication 243-2. All procedures in this test method are included in IEC 243-2. Differences between this test method and IEC 243-2 are largely editorial.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 7.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard6 pagesEnglish language
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
5.1 It is possible for insulating materials used in high-voltage equipment to be subjected to transient voltage stresses, resulting from such causes as nearby lightning strokes. This is particularly true of apparatus such as transformers and switchgear used in electrical-power transmission and distribution systems. The ability of insulating materials to withstand these transient voltages is important in establishing the reliability of apparatus insulated with these materials.
5.2 Transient voltages caused by lightning will be of either positive or negative polarity. In a symmetrical field between identical electrodes, the polarity has no effect on the breakdown strength. However, with dissimilar electrodes there can be a pronounced polarity effect. It is common practice when using dissimilar electrodes, to make negative that electrode at which the higher gradient will appear. When asymmetrical electrodes are used for testing materials with which the tester has no previous experience or knowledge, it is recommended that he make comparative tests with positive polarity and negative polarity applied to the higher gradient, or smaller electrode, to determine which polarity produces the lower breakdown voltage.
5.3 The standard wave shape is a 1.2 by 50-μs wave, reaching peak voltage in approximately 1.2 μs and decaying to 50 % of peak voltage in approximately 50 μs after the beginning of the wave. This wave is intended to simulate a lightning stroke that strikes a system without causing failure on the system.
5.4 For most materials, the impulse dielectric strength will be higher than either its power frequency alternating voltage or its direct voltage dielectric strengths. Because of the short time involved, dielectric heating and other thermal effects are largely eliminated during impulse testing. Thus, the impulse test gives values closer to the intrinsic breakdown strength than do longer time tests. From comparisons of the impulse dielectric strength with th...
SCOPE
1.1 This test method covers the determination of dielectric strength of solid electrical insulating materials under simulated-lightning impulse conditions.
1.2 Procedures are given for tests using standard 1.2 by 50 μs full-wave impulses.
1.3 This test method is intended for use in determining the impulse dielectric strength of insulating materials, either using simple electrodes or functional models. It is not intended for use in impulse testing of apparatus.
1.4 This test method is similar to IEC Publication 243-3. All procedures in this test method are included in IEC 243-3. Differences between this test method and IEC 243-3 are largely editorial.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 9.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard4 pagesEnglish language
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Controlled relative humidity environments are important for conditioning materials for shelf-life studies or for investigating the change in physical or dielectric properties after exposure.
4.2 The use of aqueous-glycerin solutions reduces the possibility of contamination of the materials or corrosion of electrode systems which would be more likely to result from saturated salt or acid water solutions.
4.3 Applicable material specifications shall state the exposure conditions, including time, temperature and relative humidity that a material is to be subjected to before subsequent testing. Typical conditions are given in Practice D618 or D6054.
SCOPE
1.1 This practice describes a method for obtaining constant relative humidity ranging from 30 to 98 % at temperatures ranging from 0 to 70°C in relatively small containers by means of an aqueous glycerin solution.
1.2 This practice is applicable for closed systems such as environmental conditioning containers.
1.3 This practice is not recommended for the generation of continuous (flowing) streams of constant humidity unless precautionary criteria are followed to ensure source stability.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard3 pagesEnglish language
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This is a laboratory test designed to simulate the effects of (1) the presence of rough interfaces between conductor or semiconductive screen and primary insulation in an insulation system, (2) the presence of foreign particles (contaminants) in an insulation system, and (3) the presence of small voids or cavities within the insulation.
5.2 This test method provides comparative data. The degree of correlation with actual performance in service has not been established.
SCOPE
1.1 This test method covers the evaluation and comparison of the resistance of solid organic dielectric materials to the initiation or growth, or both, of tubular tree-like channels resulting from partial discharge (corona) and molecular decomposition that occur in the region of very high, diverging electric fields.3,4
1.2 This test method is primarily for use at a power frequency of 50 or 60 Hz.
1.3 The test is able to be carried out at room temperature or temperatures above or below room temperature. The temperature shall not exceed the softening or melting point of the sample material.
1.4 This test method can be used for any solid material into which needles can be cast, molded, or inserted with heat after molding. The resistance to tree initiation is measured by the double-needle characteristic voltage, which is only applicable to non-opaque materials so that tree can be observed optically. The resistance to tree initiation and growth is reported by the double-needle voltage life, which is applicable to both opaque and non-opaque materials.
1.5 The values stated in SI units are to be regarded as the standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard6 pagesEnglish language
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
4.1 This test method applies to the measurement of SE of planar materials under normal incidence, far-field, plane-wave conditions (E and H tangential to the surface of the material).
4.2 The uncertainty of the measured SE values is a function of material, mismatches throughout the transmission line path, dynamic range of the measurement system, and the accuracy of the ancillary equipment. An uncertainty analysis is given in Appendix X1 to illustrate the probability of uncertainty achieved by an experienced operator using good equipment. Deviations from the procedure in this test method will increase this uncertainty.
4.3 Approximate near-field values of SE can be calculated for both E or H sources by using measured values of far-field SE. A program can be generated from the source code in Appendix X2 that is suitable for use on a personal computer.
4.4 This test method measures the net SE caused by reflection and absorption. The reflected and absorbed power measurement is accomplished by the addition of a calibrated bidirectional coupler to the input of the holder.
SCOPE
1.1 This test method provides a procedure for measuring the electromagnetic (EM) shielding effectiveness (SE) of a planar material for a plane, far-field EM wave. From the measured data, near-field SE values can be calculated for magnetic (H) sources for electrically thin specimens.2,3 Electric (E) field SE values are also able to be calculated from this same far-field data, but their validity and applicability have not been established.
1.2 The measurement method is valid over a frequency range of 30 MHz to 1.5 GHz. These limits are not exact, but are based on decreasing displacement current as a result of decreased capacitive coupling at lower frequencies and on overmoding (excitation of modes other than the transverse electromagnetic mode (TEM)) at higher frequencies for the size of specimen holder described in this test method. Select any number of discrete frequencies within this range. For electrically thin, isotropic materials with frequency independent electrical properties of conductivity, permittivity, and permeability, measurements will possibly be needed at only a few frequencies as the far-field SE values will be independent of frequency. If the material is not electrically thin or if any of the parameters vary with frequency, make measurements at several frequencies within the band of interest.
1.3 This test method is not applicable to cables or connectors.
1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard11 pagesEnglish language
- Standard11 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Whenever two dissimilar materials are contacted and separated, excess electrostatic charge (triboelectric charge) will be found on these materials if at least one of the materials is a good insulator. This excess charge gives rise to electric fields which can exert forces on other objects. If these fields exceed the breakdown strength of the surrounding gas, a disruptive discharge (spark) can occur. The heat from this discharge can ignite explosive atmospheres, the light can fog photosensitized materials, and the current flowing in a static discharge can cause catastrophic failure of solid state devices. Electric forces can be used beneficially, as in electrostatic copying, spray painting and beneficiation of ores. They can be detrimental as when they attract dirt to a surface or when they cause sheets to stick together. Since most plastic materials in use today have very good insulating qualities, it is difficult to avoid generation of static electricity. Since it depends on many parameters, it is difficult to generate static electricity reliably and reproducibly.
SCOPE
1.1 This test method covers the generation of electrostatic charge, the measurement of this charge and its associated electric field, and the test conditions which must be controlled in order to obtain reproducible results. This test method is applicable to both solids and liquids. This test method is not applicable to gases, since a transfer of a gas with no solid impurities in it does not generate an electrostatic charge. This test method also does not cover the beneficial uses of static electrification, its associated problems or hazards, or the elimination or reduction of unwanted electrostatic charge.2
1.2 The values stated in SI units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard10 pagesEnglish language
- Standard10 pagesEnglish language
SIGNIFICANCE AND USE
7.1 Bond strength values obtained by flexural tests provide information with regard to the bond strength of a particular self-bonding outer coating in combination with a particular round film-insulated magnet wire when measured under conditions described in this test method.
SCOPE
1.1 These test methods cover procedures for testing film-insulated magnet wire that is used in electrical apparatus. These test methods are intended primarily for the evaluation of the electrical insulating materials used. The intent is that these test methods be used, except where modified, by individual specifications for particular applications.
1.2 These test methods present different procedures for evaluating given properties of round, rectangular or square, copper or aluminum film-insulated magnet wire.
1.3 The values stated in inch-pound units are the standard. The SI units in parentheses are provided for information only.
1.4 The test methods appear in the following sections:
Sections
Bond Strength
4 – 12
Burnout (AC Overload Resistance)
13 – 21
Chemical Resistance
22 – 28
Coefficient of Friction
29 – 37
Continuity, DC High Voltage
38 – 45
Continuity, DC Low Voltage
46 – 53
Completeness of Cure
54 – 60
Cut-Through Temperature (Thermoplastic Flow)
61 – 68
Dielectric Breakdown AC Voltage
69 – 75
Dielectric Breakdown AC Voltage after Bending
76 – 82
Dielectric Breakdown AC Voltage at Elevated Temperatures
83 – 89
Dielectric Breakdown AC Voltage after Conditioning in Refrigerant Atmosphere
90 – 99
Dimensional Measurement
100 – 106
Dissipation Factor Measurement
107 – 114
Electrical Resistance
115 – 121
Elongation
122 – 129
Extractables, Refrigerant
130 – 140
Film Adherence and Flexibility
141 – 148
Formability:
a) Elastic Ratio
152
b) Low Stress Elongation
153
c) Spring Back
154-155
Heat Shock
156 – 162
Oiliness
163 – 169
Scrape Resistance, Unidirectional
170 – 177
Solderability
178 – 185
Resistance to Insulating Liquids and Hydrolytic Stability
186 – 195
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in 9.5, 19.1, 19.3, 19.8, 52.1, 58, 59.1, 74.1, 112.1, 135.4, and 182.3.
Note 1: This test method is related to IEC 60851. Since both methods contain multiple test procedures, many procedures are technically equivalent while others differ significantly.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard36 pagesEnglish language
- Standard36 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This is a laboratory test designed to simulate the growth of vented water-trees in the solid dielectric insulating material initiated by a sharp protrusion at the insulating and conductive interface under a wet environment in a high electrical field. Water-treeing is the phenomenon which describes the appearance of tree-like growth in organic dielectrics under an ac field when exposed to moist environments. Two types of water-trees are formed. Bow tie trees (within the dielectric) and vented water-trees formed from conductive/insulating material interface into the insulating material. The water-trees referred to in this test method are the vented type. The insulating material is the solid dielectric organic material. The conductive material is the salt solution. This salt solution is used on both sides of the insulating material to simulate the same inner and outer semiconductive shields saturated with moisture between the insulation layer used in a medium-voltage underground power cable.
5.2 This test method provides comparative data. The degree of correlation with the performance in service has not been established.
5.3 The standard test conditions are designed to grow a sufficient water-tree length for most solid dielectric insulating materials of interest before electrical breakdown occurs. Materials with a very high resistance to water-tree growth require a longer time under test conditions (such as 180 days) or higher voltage (such as 10 or 15 kV) in order to differentiate their performance. For materials with a very low resistance to water-tree growth, electrical breakdown will occur during the 30-day testing time in most instances. A shorter testing time (such as one or ten days) is recommended to prevent electrical breakdown during testing for those low water-tree resistant materials.
5.4 Other voltages, frequencies, temperatures, aqueous solutions, and defects are able to be used to evaluate specific materials for specific applications. Tempe...
SCOPE
1.1 This test method covers the relative resistance to vented water-tree growth in solid translucent thermoplastic or cross-linked electrical insulating materials. This test method is especially applicable to extruded polymeric insulation materials used in medium-voltage cables.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitation prior to use. For specific hazard statements see 8.1.
1.4 There is no similar or equivalent IEC standard.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
SCOPE
1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 1 GHz to over 20 GHz. These limits are not exact and depend on the size of the specimen, the size of coaxial air line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. For a given air line size, the upper frequency is also limited by the onset of higher order modes that invalidate the dominant-mode transmission line model and the lower frequency is limited by the smallest measurable phase shift through a specimen. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. The coaxial fixture is preferred over rectangular waveguide fixtures when broadband data are desired with a single sample or when only small sample volumes are available, particularly for lower frequency measurements.
1.3 The values stated in either SI units of in inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore each system shall be used independently of the other. Combining values from the two systems is likely to result in non conformance with the standard. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
SCOPE
1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 100 MHz to over 40 GHz. These limits are not exact and depend on the size of the specimen, the size of rectangular waveguide transmission line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. Use of multiple rectangular waveguide transmission line sizes are required to cover this entire frequency range (100 MHz to 40 GHz). This test method can also be generally applied to circular waveguide test fixtures. The rectangular waveguide fixture is preferred over coaxial fixtures when samples have in-plane anisotropy or are difficult to manufacture precisely.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are in inch-pound units and are included for information only. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Electrical equipment can fail as a result of electrical tracking of insulating material that is exposed to various contaminating environments and surface conditions. This method is an accelerated test which at relatively low test voltages, provides a comparison of the performance of insulating materials under wet and contaminated conditions. The comparative tracking index is not related directly to the suitable operating voltage in service.
5.2 When organic electrical insulating materials are subjected to conduction currents between electrodes on their surfaces, many minute tree-like carbonaceous paths or tracks are developed near the electrodes. These tracks are oriented randomly, but generally propagate between the electrodes under the influence of the applied potential difference. Eventually a series of tracks spans the electrode gap, and failure occurs by shorting of the electrodes.
5.3 The conditions specified herein are intended to produce a condition conducive to the formation of surface discharges and possible subsequent tracking. Test conditions are chosen to accelerate a process that is reproducible. Consequently, they rarely reproduce the varied conditions found in actual service. Therefore, while tracking tests serve to differentiate materials under given conditions, results of tracking tests cannot be used to infer either direct or comparative service behavior of an application design. Rather, the results provide a tool for judging the suitability of materials for a given application. The suitability can only be verified through testing the design in actual end use or under conditions which simulate end use as closely as possible.
5.4 The results have been used for insulation coordination of equipment with rated voltage up to 1000 Vac or 1500 Vdc connected to low-voltage supply systems (higher voltages permitted in internal circuits). The complete principles of insulation coordination involve the consideration of the combination of clearanc...
SCOPE
1.1 This test method evaluates in a short period of time the low-voltage (up to 600 V) track resistance or comparative tracking index (CTI) of materials in the presence of aqueous contaminants.
1.2 The values stated in metric (SI) units are to be regarded as standard. The inch-pound equivalents of the metric units are approximate.
1.3 This test method is technically equivalent to the version of IEC Publication 112 cited in 2.2. However, the 2007 version of IEC 60112 Fourth Edition yields numerical CTI values that are very likely to differ significantly from this test method.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard6 pagesEnglish language
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is useful for the comparison of materials, as a quality control test, and for specification purposes.
5.2 This test method is useful in the selection and use of materials in wires, cables, bushings, high-voltage rotating machinery, and other electrical apparatus in which shielding or the distribution of voltage stress is of value.
5.3 Commercially available “moderately conductive” materials frequently are comprised of both conductive and resistive components (that is, cellulose fibers with colloidal carbon black particles attached to portions of the surfaces of those fibers, or discrete conductive particles adhered to the surfaces of electrical insulating polymers). Such commercially available materials are often manufactured in a manner that results in anisotropy of electrical conduction. Hence, the significance of tests using this test method depends upon the orientation of the specimen tested to the direction of the electric field and the relationship between this orientation and the orientation of the material in the electrical apparatus, which uses these materials.
SCOPE
1.1 This test method covers the determination of electrical resistance and electrical resistivity of materials that are generally categorized as moderately conductive and are neither good electrical insulators nor good conductors.
1.2 This test method applies to the materials that exhibit volume resistivity in the range of 100 to 107 Ω-cm or surface resistivity in the range of 103 to 107 Ω (per square).
1.3 This test method is designed for measurements at standard conditions of 23 °C and 50 % relative humidity, but its principles of operation can be applied to specimens measured at lower or higher temperatures and relative humidities.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 8.3.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard5 pagesEnglish language
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
5.1 These test methods differentiate solid electrical insulating materials on the basis of their resistance to the action of voltage stresses along the surface of the solid when wet with an ionizable, electrically conductive liquid contaminant.
5.2 These test methods quantitatively evaluate, in a relative manner, the effects upon an insulating material resulting from the action of electrical discharges upon a material surface. The effects are similar to those that may occur in service under the influence of dirt combined with moisture condensed from the atmosphere.
5.2.1 In the field, the conditions resulting in electrical discharges occur sporadically. Degradation, often in the form of a conducting “track,” develops very slowly until it ultimately bridges the space between conductors thus causing complete electrical breakdown.
5.2.2 In these test methods, the conducting liquid contaminant is continuously supplied at an optimum rate to the surface of a test specimen in such a fashion that essentially continuous electrical discharge can be maintained.
5.2.3 By producing continuous surface discharge with controlled energy it is possible, within a few hours, to cause specimen failure which is similar to failure occurring under long-time exposure to the erratic conditions of service in the field.
5.2.4 The test conditions, which are standardized and accelerated, do not reproduce all of the conditions encountered in service. Use caution when making either direct or comparative service behavior inferences derived from the results of tracking tests.
5.3 The time-to-track a 1-in. (25 mm) distance at a specified voltage between electrodes separated 2 in. (50 mm) has also been found useful in categorizing insulating materials for indoor and protected outdoor applications, such as metal-clad switchgear.
5.4 The initial tracking voltage has been found useful for evaluating insulating materials to be used at high voltages or outdoors and unprotected, as well...
SCOPE
1.1 These test methods cover the evaluation of the relative tracking and erosion resistance of insulating solids using the liquid-contaminant, inclined-plane test.2 The following test methods also can be used to evaluate the tracking resistance of materials: Test Method D2132 (contaminants: dust and fog) and Test Method D3638 (contaminant: conductive liquid drops).
1.2 Two tracking and one erosion test procedure are described:
1.2.1 A “variable voltage method” to evaluate resistance to tracking.
1.2.2 A “time-to-track method” to evaluate resistance to tracking.
1.2.3 A method for quantitative determination of erosion (Annex A1).
1.3 While a particular contaminant solution is specified, other concentrations of the same contaminant, or different contaminants are used to simulate different environmental or service conditions.
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.5 Although this standard and IEC 60587-2007, “Test Methods for Evaluating Resistance to Tracking and Erosion for Electrical Insulating Materials Used Under Severe Ambient Conditions,” differ in approach or detail, data obtained using either are technically equivalent.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 9.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations is...
- Standard12 pagesEnglish language
- Standard12 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Permittivity—Insulating materials are used in general in two distinct ways, (1) to support and insulate components of an electrical network from each other and from ground, and (2) to function as the dielectric of a capacitor. For the first use, it is generally desirable to have the capacitance of the support as small as possible, consistent with acceptable mechanical, chemical, and heat-resisting properties. A low value of permittivity is thus desirable. For the second use, it is desirable to have a high value of permittivity, so that the capacitor is able to be physically as small as possible. Intermediate values of permittivity are sometimes used for grading stresses at the edge or end of a conductor to minimize ac corona. Factors affecting permittivity are discussed in Appendix X3.
5.2 AC Loss—For both cases (as electrical insulation and as capacitor dielectric) the ac loss generally needs to be small, both in order to reduce the heating of the material and to minimize its effect on the rest of the network. In high frequency applications, a low value of loss index is particularly desirable, since for a given value of loss index, the dielectric loss increases directly with frequency. In certain dielectric configurations such as are used in terminating bushings and cables for test, an increased loss, usually obtained from increased conductivity, is sometimes introduced to control the voltage gradient. In comparisons of materials having approximately the same permittivity or in the use of any material under such conditions that its permittivity remains essentially constant, it is potentially useful to consider also dissipation factor, power factor, phase angle, or loss angle. Factors affecting ac loss are discussed in Appendix X3.
5.3 Correlation—When adequate correlating data are available, dissipation factor or power factor are useful to indicate the characteristics of a material in other respects such as dielectric breakdown, moisture content, degree o...
SCOPE
1.1 These test methods cover the determination of relative permittivity, dissipation factor, loss index, power factor, phase angle, and loss angle of specimens of solid electrical insulating materials when the standards used are lumped impedances. The frequency range addressed extends from less than 1 Hz to several hundred megahertz.
Note 1: In common usage, the word relative is frequently dropped.
1.2 These test methods provide general information on a variety of electrodes, apparatus, and measurement techniques. A reader interested in issues associated with a specific material needs to consult ASTM standards or other documents directly applicable to the material to be tested.2,3
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see 10.2.1.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard20 pagesEnglish language
- Standard20 pagesEnglish language
ABSTRACT
These test methods cover the testing of fibrous-insulated electrical conductors, commonly referred to as magnet wire, which are used in electrical apparatus. The test methods are intended primarily for evaluation of the electrical insulating materials used. It is intended that these test methods be used, except where modified by individual specifications for particular applications. This elongation testing method covers the determination of the elongation of fibrous insulated magnet wire that results in a fracture of the conductor. The electrical resistance testing method covers the determination of the electrical resistance of fibrous insulated magnet wire conductors. The fibrous coverage testing method covers the determination of the quality of fibrous servings on round magnet wire or bare conductor. The measurement of dimensions test methods determine the dimensions of the bare or film insulated conductor and the fibrous-insulated magnet wire. The adhesion and flexibility test method covers the evaluation of the flexibility and adherence of varnished fibrous glass, and varnished or unvarnished fibrous polyester-glass insulating material on either bare conductor, or film-insulated magnet wire. The dielectric breakdown voltage test method covers the determination of the dielectric breakdown voltage in air of insulation on round, rectangular, and square wires at commercial power frequencies.
SCOPE
1.1 These test methods cover the testing of fibrous-insulated electrical conductors, commonly referred to as magnet wire, which are used in electrical apparatus. The test methods are intended primarily for evaluation of the electrical insulating materials used. It is intended that these test methods be used, except where modified by individual specifications for particular applications.
1.1.1 These test methods apply to those magnet wires that are fiber-covered and in which the substrate is bare conductor or is coated with an underlying insulating film as covered by Test Methods D1676. Fiber-covered wires are produced by serving helically or wrapping fibers or fibrous-tape insulation uniformly around the wire in single and multiple layers. The served or wrapped materials are bonded or not bonded to the underlying wire.
1.2 The test methods appear in the following sections:
Procedure
Section
Measurement of Dimensions
7
Electrical Resistance of Conductors
5
Elongation
4
Adhesion and Flexibility
8
Fibrous Coverage
6
Dielectric Breakdown Voltage
9
1.3 This standard and IEC 60851 are similar if not equivalent in technical content.
1.4 This standard and NEMA MW 1000 are similar if not equivalent in technical content.
1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See 8.4.1 and 9.4.1 for specific caution statements.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Some electrical properties, such as dielectric strength, vary with the thickness of the material. Determination of certain properties, such as relative permittivity (dielectric constant) and volume resistivity, usually require a knowledge of the thickness. Design and construction of electrical machinery require that the thickness of insulation be known.
SCOPE
1.1 These test methods cover the determination of the thickness of several types of solid electrical insulating materials employing recommended techniques. Use these test methods except as otherwise required by a material specification.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, each system shall be used independently of the other. It is possible that combining values from the two systems will result in non-conformance with the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard12 pagesEnglish language
- Standard12 pagesEnglish language
SIGNIFICANCE AND USE
4.1 These tests are useful for specification and control purposes during the manufacture, purchase, and use of the magnet-wire enamels, and for determining uniformity of batches.
SCOPE
1.1 These test methods cover testing liquid enamel coatings used to produce film-insulated magnet wire.
1.2 The values stated in either lbs/gal or SI units are to be regarded separately as standard.
1.3 The test methods appear as follows:
Sections
Density
6 – 10
Determined Solids
16 – 22
Effective Solids
31 – 37
Flash Point
11 – 15
Infrared Analysis
45 – 50
Stack Loss
23 – 30
Viscosity
38 – 44
1.4 There is no known IEC equivalent document.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard7 pagesEnglish language
- Standard7 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
SCOPE
1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 100 MHz to over 40 GHz. These limits are not exact and depend on the size of the specimen, the size of rectangular waveguide transmission line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. Use of multiple rectangular waveguide transmission line sizes are required to cover this entire frequency range (100 MHz to 40 GHz). This test method can also be generally applied to circular waveguide test fixtures. The rectangular waveguide fixture is preferred over coaxial fixtures when samples have in-plane anisotropy or are difficult to manufacture precisely.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are in inch-pound units and are included for information only. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Electrical equipment has the potential to fail as a result of electrical tracking of insulating material that is exposed to various contaminating environments and surface conditions. A number of ASTM and other tests have been designed to quantify behavior of materials, especially at relatively high voltages. This method is an accelerated test which, at relatively low test voltages, provides a comparison of the performance of insulating materials under wet and contaminated conditions. The Tracking Index—Copper Electrodes test is not related directly to the suitable operating voltage in service.
5.2 When organic electrical insulating materials are subjected to conduction currents between electrodes on their surfaces, many minute tree-like carbonaceous paths or tracks are developed near the electrodes. These tracks are oriented randomly, but generally propagate between the electrodes under the influence of the applied potential difference. Eventually a series of tracks spans the electrode gap, and failure occurs by shorting of the electrodes.
5.3 As in other tracking test methods, for example, IEC 112 and Test Method D3638, this test method specifies test procedures that are intended to promote the formation of surface discharges which will produce carbon tracks in a reproducible manner. Since these conditions rarely reproduce the actual conditions encountered in service, the results of tracking tests cannot be used to infer either direct or relative service behavior of a material in a specific design application. Tracking tests can be used for screening purposes only. Suitability is verified through testing of the material in actual end use or under conditions that closely simulate actual end use.
5.4 The use of copper electrodes in this type of test was developed at the University of Cincinnati, NEMA laboratory. It is felt by the members of the Industrial Laminates Section of NEMA that using copper electrodes gives a more realistic value for a tracking i...
SCOPE
1.1 This test method was developed using copper electrodes to evaluate the low-voltage (up to 600 V) tracking resistance of materials in the presence of aqueous contaminants.2
Note 1: At this time, only industrial laminates have been examined using this method, which was developed at the National Manufacturers Electrical Association (NEMA) laboratory located at the University of Cincinnati. It was found that a closer end point (less scatter) was obtained than with platinum electrodes, and materials tested tended to be ranked by resin system.
1.1.1 It is acceptable to consider other electrode materials for use with this test method depending upon the application of the insulating material.
1.2 This test method is similar to Test Method D3638, which determines the comparative tracking index of materials using platinum electrodes to produce the tracking on the specimen surface.
1.3 The values stated in metric (SI) units are the standard. The inch-pound equivalents of the metric units are approximate.
1.4 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.
1.5 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.
- Standard5 pagesEnglish language
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Permittivity and dissipation factor are fundamental design parameters for design of microwave circuitry. Permittivity plays a principal role in determining the wavelength and the impedance of transmission lines. Dissipation factor (along with copper losses) influence attenuation and power losses.
5.2 This test method is suitable for polymeric materials having permittivity in the order of two to eleven. Such materials are popular in applications of stripline and microstrip configurations used in the 1 to 18 GHz range.
5.3 This test method is suitable for design, development, acceptance specifications, and manufacturing quality control.
Note 2: See Appendix X1 for additional information regarding significance of this test method and the application of the results.
SCOPE
1.1 This test method permits the rapid measurement of apparent relative permittivity and loss tangent (dissipation factor) of metal-clad polymer-based circuit substrates in the X-band (8 to 12.4 GHz).
1.2 This test method is suitable for testing PTFE (polytetrafluorethylene) impregnated glass cloth or random-oriented fiber mats, glass fiber-reinforced polystyrene, polyphenyleneoxide, irradiated polyethylene, and similar materials having a nominal specimen thickness of 1/16 in. (1.6 mm). The materials listed in the preceding sentence have been used in commercial applications at nominal frequency of 9.6 GHz.
Note 1: See Appendix X1 for additional information about range of permittivity, thickness other than 1.6 mm, and tests at frequencies other than 9.6 GHz.
1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard13 pagesEnglish language
- Standard13 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Design calculations for radio frequency (RF), microwave, and millimetre-wave components require the knowledge of values of complex permittivity and permeability at operating frequencies. This test method is useful for evaluating small experimental batch or continuous production materials used in electromagnetic applications. Use this method to determine complex permittivity only (in non-magnetic materials), or both complex permittivity and permeability simultaneously.
SCOPE
1.1 This test method covers a procedure for determining relative complex permittivity (relative dielectric constant and loss) and relative magnetic permeability of isotropic, reciprocal (non-gyromagnetic) solid materials. If the material is nonmagnetic, it is acceptable to use this procedure to measure permittivity only.
1.2 This measurement method is valid over a frequency range of approximately 1 to over 20 GHz. These limits are not exact and depend on the size of the specimen, the size of coaxial air line used as a specimen holder, and on the applicable frequency range of the network analyzer used to make measurements. The size of specimen dimension is limited by test frequency, intrinsic specimen electromagnetism properties, and the request of algorithm. For a given air line size, the upper frequency is also limited by the onset of higher order modes that invalidate the dominant-mode transmission line model and the lower frequency is limited by the smallest measurable phase shift through a specimen. Being a non-resonant method, the selection of any number of discrete measurement frequencies in a measurement band would be suitable. The coaxial fixture is preferred over rectangular waveguide fixtures when broadband data are desired with a single sample or when only small sample volumes are available, particularly for lower frequency measurements
1.3 The values stated in either SI units of in inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore each system shall be used independently of the other. Combining values from the two systems is likely to result in non conformance with the standard. The equations shown here assume an e+jωt harmonic time convention.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is useful in research and quality control for evaluating insulating materials and systems since they provide for the measurement of the endurance used to compare different materials to the action of corona on the external surfaces. A poor result on this test does not indicate that the material is a poor selection for use at high voltage or at high voltage stress in the absence of surface corona; surface corona is not the same as corona that occurs in internal cavities. (See Test Methods D3382.)
5.2 This test method is also useful for comparison between materials of the same relative thickness. When agreed upon between the buyer and the seller, it is acceptable to express any differences in terms of relative time to failure or the magnitude of voltage stress (kV/mm or kV/in.) required to produce failure in a specified number of hours.
5.3 It is possible for this test method to also be used to examine the effects of different processing parameters on the same insulating material, such as residual strains produced by quenching, high levels of crystallinity or molding processes that control the concentration and sizes of gas-filled cavities.
5.4 The data are generated in the form of a set of values of lifetimes at a voltage. The dispersion of failure times is analyzed using one of the methods below:
5.4.1 Weibull Probability Plot.
5.4.2 Statistically (see IEEE 930-1987 for additional information), to yield an estimate of the central value of the distribution and its standard deviation.
5.4.3 Truncating a test at the time of the fifth failure of a set of nine and using that time as the measure of the central tendency. Two such techniques are described in 10.2.
5.5 This test method intensifies some of the more commonly met conditions of corona attack so that materials are able to be evaluated in a time that is relatively short compared to the life of the equipment. As with most accelerated life tests, caution is necessary in extra...
SCOPE
1.1 This test method determines the voltage endurance of solid electrical insulating materials for use at commercial power frequencies under the action of corona (see Note 1). This test method is more meaningful for rating materials with respect to their resistance to prolonged ac stress under corona conditions for comparative evaluation between materials.
Note 1: The term “corona” is used almost exclusively in this test method instead of “partial discharge,” because it is a visible glow at the edge of the electrode interface that is the result of partial discharge. Corona, as defined in Terminology D1711, is “visible partial discharges in gases adjacent to a conductor.”
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 7.
- Standard9 pagesEnglish language
- Standard9 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is intended for use as a control and acceptance test for direct-voltage applications. It can also be used in the partial evaluation of material for specific end uses and as a means for detecting changes in material due to specific deteriorating causes.
5.2 Experience indicates that the breakdown value obtained with direct voltage usually will be approximately 2 to 4 times the rms value of the 60-Hz alternating-voltage breakdown.
5.3 For a nonhomogeneous test specimen, the distribution of voltage stress within the specimen is determined by impedance (largely capacitive) with alternating voltage. With an increasing direct voltage, the voltage distribution will still be largely capacitive, although this depends partly on the rate of voltage increase. After steady application of direct voltage the voltage division across the test specimen is determined by resistance. The choice of direct or alternating voltage depends upon the purpose for which the breakdown test is to be used, and to some extent, on the intended application of the material.
5.4 A more complete discussion of the significance of dielectric breakdown tests is given in Appendix X1 of this method and in Appendix X1 of Test Method D149. Those appendix sections of Test Method D149 that refer to alternating voltage are not applicable to the direct-voltage method.
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1.1 This test method covers the determination of dielectric breakdown voltage and dielectric strength of solid electrical insulating materials under direct-voltage stress.
1.2 Since some materials require special treatment, reference shall also be made to ASTM specifications or to the test method directly applicable to the material to be tested. See Test Method D149 for the determination of dielectric strength of electrical insulating materials at commercial power frequencies.
1.3 This test method is similar to IEC Publication 243-2. All procedures in this test method are included in IEC 243-2. Differences between this test method and IEC 243-2 are largely editorial.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 7.
- Standard6 pagesEnglish language
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Insulating materials are used to isolate components of an electrical system from each other and from ground, as well as to provide mechanical support for the components. For this purpose, it is generally desirable to have the insulation resistance as high as possible, consistent with acceptable mechanical, chemical, and heat-resisting properties. Since insulation resistance or conductance combines both volume and surface resistance or conductance, its measured value is most useful when the test specimen and electrodes have the same form as is required in actual use. Surface resistance or conductance changes rapidly with humidity, while volume resistance or conductance changes slowly with the total change being greater in some cases.
5.2 Resistivity or conductivity is used to predict, indirectly, the low-frequency dielectric breakdown and dissipation factor properties of some materials. Resistivity or conductivity is often used as an indirect measure of: moisture content, degree of cure, mechanical continuity, or deterioration of various types. The usefulness of these indirect measurements is dependent on the degree of correlation established by supporting theoretical or experimental investigations. A decrease of surface resistance results either in an increase of the dielectric breakdown voltage because the electric field intensity is reduced, or a decrease of the dielectric breakdown voltage because the area under stress is increased.
5.3 All the dielectric resistances or conductances depend on the length of time of electrification and on the value of applied voltage (in addition to the usual environmental variables). These must be known and reported to make the measured value of resistance or conductance meaningful. Within the electrical insulation materials industry, the adjective “apparent” is generally applied to resistivity values obtained under conditions of arbitrarily selected electrification time. See X1.4.
5.4 Volume resistivity or conductivi...
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1.1 These test methods cover direct-current procedures for the measurement of dc insulation resistance, volume resistance, and surface resistance. From such measurements and the geometric dimensions of specimen and electrodes, both volume and surface resistivity of electrical insulating materials can be calculated, as well as the corresponding conductances and conductivities.
1.2 These test methods are not suitable for use in measuring the electrical resistance/conductance of moderately conductive materials. Use Test Method D4496 to evaluate such materials.
1.3 This standard describes several general alternative methodologies for measuring resistance (or conductance). Specific materials can be tested most appropriately by using standard ASTM test methods applicable to the specific material that define both voltage stress limits and finite electrification times as well as specimen configuration and electrode geometry. These individual specific test methodologies would be better able to define the precision and bias for the determination.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard18 pagesEnglish language
- Standard18 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The high-voltage, low-current type of arc resistance test is intended to simulate only approximately such service conditions as exist in alternating current circuits operating at high voltage, but at currents limited to units and tens of milliamperes.
4.2 In order to distinguish more easily among materials that have low arc resistance, the early stages of this test method are mild, and the later stages are successively more severe. The arc occurs intermittently between two electrodes resting on the surface of the specimen, in normal or inverted orientation. The severity is increased in the early stages by successively decreasing to zero the interval between flashes of uniform duration, and in later stages by increasing the current.
4.3 Four general types of failure have been observed:
4.3.1 Many inorganic dielectrics become incandescent, whereupon they are capable of conducting the current. Upon cooling, however, they return to their earlier insulating condition.
4.3.2 Some organic compounds burst into flame without the formation of a visible conducting path in the substance.
4.3.3 Others are seen to fail by “tracking,” that is, a thin wiry line is formed between the electrodes.
4.3.4 The fourth type occurs by carbonization of the surface until sufficient carbon is present to carry the current.
4.4 Materials often fail within the first few seconds after a change in the severity stage. When comparing the arc resistance of materials, much more weight shall be given to a few seconds that overlap two stages than to the same elapsed time within a stage. Thus, there is a much greater difference in arc resistance between 178 and 182 s than between 174 and 178 s.Note 3—Some investigators have reported attempts to characterize the remaining insulating value of the damaged area after failure by allowing the specimen to cool to room temperature, without disturbance of the original position of the electrodes, and then either (1) measuring the insulatio...
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1.1 This test method covers, in a preliminary fashion, the differentiation of similar materials’ resistance to the action of a high-voltage, low-current arc close to the surface of insulation, when a conducting path is formed causing the material to become conducting due to the localized thermal and chemical decomposition and erosion.
1.2 The usefulness of this test method is very severely limited by many restrictions and qualifications, some of which are described in the following paragraphs and in Section 5. Generally, this test method shall not be used in material specifications. Whenever possible, alternative test methods shall be used, and their development is encouraged.
1.3 This test method will not, in general, permit conclusions to be drawn concerning the relative arc resistance rankings of materials that are potentially subjected to other types of arcs: for example, high voltage at high currents, and low voltage at low or high currents (promoted by surges or by conducting contaminants).
1.4 The test method is intended, because of its convenience and the short time required for testing, for preliminary screening of material, for detecting the effects of changes in formulation, and for quality control testing after correlation has been established with other types of simulated service arc tests and field experience. Because this test method is usually conducted under clean and dry laboratory conditions rarely encountered in practice, it is possible that the prediction of a material's relative performance in typical applications and in varying “clean to dirty” environments will be substantially altered (Note 1). Caution is urged against drawing strong conclusions without corroborating support of simulated service tests and field testing. Rather, this test method is useful for preliminary evaluation of changes in structure and composition without the complicating influence of environmental conditions, esp...
- Standard10 pagesEnglish language
SIGNIFICANCE AND USE
5.1 These test methods are useful in research and quality control for evaluating insulating materials and systems since they provide for the measurement of charge transfer and energy loss due to partial discharges(4) (5) (6).
5.2 Pulse measurements of partial discharges indicate the magnitude of individual discharges. However, if there are numerous discharges per cycle it is occasionally important to know their charge sum, since this sum can be related to the total volume of internal gas spaces that are discharging, if it is assumed that the gas cavities are simple capacitances in series with the capacitances of the solid dielectrics (7) (8).
5.3 Internal (cavity-type) discharges are mainly of the pulse (spark-type) with rapid rise times or the pseudoglow-type with long rise times, depending upon the discharge governing parameters existing within the cavity. If the rise times of the pseudoglow discharges are too long , they will evade detection by pulse detectors as covered in Test Method D1868. However, both the pseudoglow discharges irrespective of the length of their rise time as well as pulseless glow can be readily measured either by Method A or B of Test Methods D3382.
5.4 Pseudoglow discharges have been observed to occur in air, particularly when a partially conducting surface is involved. It is possible that such partially conducting surfaces will develop with polymers that are exposed to partial discharges for sufficiently long periods to accumulate acidic degradation products. Also in some applications, like turbogenerators, where a low molecular weight gas such as hydrogen is used as a coolant, it is possible that pseudoglow discharges will develop.
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1.1 These test methods cover two bridge techniques for measuring the energy and integrated charge of pulse and pseudoglow partial discharges:
1.2 Test Method A makes use of capacitance and loss characteristics such as measured by the transformer ratio-arm bridge or the high-voltage Schering bridge (Test Methods D150). Test Method A can be used to obtain the integrated charge transfer and energy loss due to partial discharges in a dielectric from the measured increase in capacitance and tan δ with voltage. (See also IEEE 286 and IEEE 1434)
1.3 Test Method B makes use of a somewhat different bridge circuit, identified as a charge-voltage-trace (parallelogram) technique, which indicates directly on an oscilloscope the integrated charge transfer and the magnitude of the energy loss due to partial discharges.
1.4 Both test methods are intended to supplement the measurement and detection of pulse-type partial discharges as covered by Test Method D1868, by measuring the sum of both pulse and pseudoglow discharges per cycle in terms of their charge and energy.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Section 7.
- Standard8 pagesEnglish language
- Standard8 pagesEnglish language
SIGNIFICANCE AND USE
5.1 The presence of partial discharges (corona) at operating voltage in an insulation system has the potential to result in a significant reduction in the life of the insulating material. Some materials are more susceptible to such discharge damage than others. This characteristic can be investigated using Test Method D2275.
5.2 The presence of partial discharges (corona) in an apparently solid insulation is a potential indication of the existence of internal cavities. Partial discharge tests have been useful in the design and inspection of molded, laminated, and composite insulation, as well as specimens in the form of cables, capacitors, transformers, bushings, stator bars, and rotating machines (1), (2), (3), (4), (5), (6), (7), (8), (9), (13), and (12). (See also AEIC CS5-87, ICEA T-24-380, IEEE 48, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005.)
5.3 Partial discharge (corona) inception and extinction voltages are used in the determination of the limiting voltage at which an insulation system will operate free of such discharges. The extinction voltage is often substantially lower than the inception voltage. Where the operating voltage is below the inception voltage but above the extinction voltage, it is possible that a transient over-voltage will initiate discharges which then continue until the voltage is lowered below the extinction voltage. Inception and extinction voltages depend upon many factors, including temperature and the rate at which the voltage is changed. After a time at a voltage, it is possible that discharges will start and stop in a nonuniform and unpredictable fashion, especially for discharges within cavities in certain materials, in particular if the discharge degradation products formed are conductive (1), (5).
5.4 The magnitude (pulse height) of a partial discharge is an indication of the amount of energy that it dissipates in the insulation system. Partial discharge magnitude and pulse rate are useful in estimating ...
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1.1 This test method covers the detection and measurement of partial discharge (corona) pulses at the terminals of an insulation system under an applied test voltage, including the determination of partial discharge (corona) inception and extinction voltages as the test voltage is raised and lowered. The test method is also useful in determining quantities such as apparent charge and pulse repetition rate together with such integrated quantities as average current, quadratic rate and power. The test method is useful for test voltages ranging in frequency from zero (direct voltage) to approximately 2000 Hz.
1.2 The test method is directly applicable to a simple insulation system that can be represented as a two-terminal capacitor (1), (2) .
1.3 The test method is also applicable to (distributed parameter) insulation systems such as high-voltage cable. Consideration must be given to attenuation and reflection phenomena in this type of system. Further information on distributed parameter systems of cables, transformers, and rotating machines will be found in Refs. (1), (2), (3), (4), (5), (6), (7), (8), and (9).2 (See AEIC CS5-87, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005.)
1.4 The test method can be applied to multi-terminal insulation systems, but at some loss in accuracy, especially where the insulation of inductive windings is involved.
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Sections 8 and 14.
- Standard11 pagesEnglish language
- Standard11 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Design calculations for such components as transmission lines, antennas, radomes, resonators, phase shifters, etc., require knowledge of values of complex permittivity at operating frequencies. The related microwave measurements substitute distributed field techniques for low-frequency lumped-circuit impedance techniques.
4.2 Further information on the significance of permittivity is contained in Test Methods D150.
4.3 These test methods are useful for specification acceptance, service evaluation, manufacturing control, and research and development of ceramics, glasses, and organic dielectric materials.
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1.1 These test methods cover the determination of relative (Note 1) complex permittivity (dielectric constant and dissipation factor) of nonmagnetic solid dielectric materials. Note 1—The word “relative” is often omitted.
1.1.1 Test Method A is for specimens precisely formed to the inside dimension of a waveguide.
1.1.2 Test Method B is for specimens of specified geometry that occupy a very small portion of the space inside a resonant cavity.
1.1.3 Test Method C uses a resonant cavity with fewer restrictions on specimen size, geometry, and placement than Test Methods A and B.
1.2 Although these methods are used over the microwave frequency spectrum from around 0.5 to 50.0 GHz, each octave increase usually requires a different generator and a smaller test waveguide or resonant cavity.
1.3 Tests at elevated temperatures are made using special high-temperature waveguide and resonant cavities.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard17 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Permittivity and dissipation factor are sensitive to changes in chemical composition, impurities, and homogeneity. Measurement of these properties is, therefore, useful for quality control and for determining the effect of environments such as moisture, heat, or radiation.
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1.1 This test method covers the determination of the relative permittivity (dielectric constant) and dissipation factor of solid dielectrics from 50 Hz to 10 MHz over a range of temperatures from −80 to 500°C.2 ,3 Two procedures are included as follows:
1.1.1 Procedure A—Using Micrometer Electrode.
1.1.2 Procedure B—Using Precision Capacitor. Note 1—In common usage the word “relative” is frequently dropped.
1.2 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method is useful for the comparison of materials, as a quality control test, and for specification purposes.
5.2 This test method is useful in the selection and use of materials in wires, cables, bushings, high-voltage rotating machinery, and other electrical apparatus in which shielding or the distribution of voltage stress is of value.
5.3 Commercially available “moderately conductive” materials frequently are comprised of both conductive and resistive components (that is, cellulose fibers with colloidal carbon black particles attached to portions of the surfaces of those fibers, or discrete conductive particles adhered to the surfaces of electrical insulating polymers). Such commercially available materials are often manufactured in a manner that results in anisotropy of electrical conduction. Hence, the significance of tests using this test method depends upon the orientation of the specimen tested to the direction of the electric field and the relationship between this orientation and the orientation of the material in the electrical apparatus, which uses these materials.
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1.1 This test method covers the determination of electrical resistance and electrical resistivity of materials that are generally categorized as moderately conductive and are neither good electrical insulators nor good conductors.
1.2 This test method applies to the materials that exhibit volume resistivity in the range of 100 to 107 Ω-cm or surface resistivity in the range of 103 to 107 Ω (per square).
1.3 This test method is designed for measurements at standard conditions of 23°C and 50 % relative humidity, but its principles of operation can be applied to specimens measured at lower or higher temperatures and relative humidities.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 8.3.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 These test methods differentiate among solid electrical insulating materials on the basis of their resistance to the action of voltage stresses along the surface of the solid when wet with an ionizable, electrically conductive liquid contaminant.
4.2 These test methods quantitatively evaluate, in a relative manner, the effects upon an insulating material resulting from the action of electrical discharges upon a material surface. The effects are similar to those that may occur in service under the influence of dirt combined with moisture condensed from the atmosphere.
4.2.1 In the field, the conditions resulting in electrical discharges occur sporadically. Degradation, often in the form of a conducting “track,” develops very slowly until it ultimately bridges the space between conductors thus causing complete electrical breakdown.
4.2.2 In these test methods, the conducting liquid contaminant is continuously supplied at an optimum rate to the surface of a test specimen in such a fashion that essentially continuous electrical discharge can be maintained.
4.2.3 By producing continuous surface discharge with controlled energy it is possible, within a few hours, to cause specimen failure which is similar to failure occurring under long-time exposure to the erratic conditions of service in the field.
4.2.4 The test conditions, which are standardized and accelerated, do not reproduce all of the conditions encountered in service. Use caution when making either direct or comparative service behavior inferences derived from the results of tracking tests.
4.3 The time-to-track a 1-in. (25-mm) distance at a specified voltage between electrodes separated 2 in. (50 mm) has also been found useful in categorizing insulating materials for indoor and protected outdoor applications, such as metal-clad switchgear.
4.4 The initial tracking voltage has been found useful for evaluating insulating materials to be used at high voltages or outdoors and unprotected, a...
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1.1 These test methods cover the evaluation of the relative tracking and erosion resistance of insulating solids using the liquid-contaminant, inclined-plane test.2 The following test methods also can be used to evaluate the tracking resistance of materials: D2132 (contaminants: dust and fog) and D3638 (contaminant: conductive liquid drops).
1.2 Two tracking and one erosion test procedure are described:
1.2.1 A “variable voltage method” to evaluate resistance to tracking.
1.2.2 A “time-to-track method” to evaluate resistance to tracking.
1.2.3 A method for quantitative determination of erosion (Annex A1).
1.3 While a particular contaminant solution is specified, other concentrations of the same contaminant, or different contaminants are used to simulate different environmental or service conditions.
1.4 The values stated in inch-pound units are to be regarded as the standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.
- Standard11 pagesEnglish language
Frequently Asked Questions
D09.12 is a Technical Committee within ASTM International. It is named "Electrical Tests". This committee has published 135 standards.
D09.12 develops ASTM standards in the area of Information technology. Currently, there are 135 published standards from this technical committee.
ASTM is a standardization organization that develops and publishes standards to support industry, commerce, and regulatory requirements.
A Technical Committee (TC) in ASTM is a group of experts responsible for developing international standards in a specific technical area. TCs are composed of national member body delegates and work through consensus to create standards that meet global industry needs. Each TC may have subcommittees (SCs) and working groups (WGs) for specialized topics.