D27 - Electrical Insulating Liquids and Gases
The promotion of knowledge pertaining to electrical insulating liquids and gases, whether of synthetic or natural origin, and the recommendation of standards pertinent to these materials. The principal materials included in this scope are oils of petroleum origin, synthetic liquids, halogenated and other gases, when used, singularly or as combinations, as electrical insulation or as an environment for electrical insulation. Standards peculiar to solid insulating materials and varnishes and the development of standards pertaining to the nonelectrical uses of liquid and gaseous materials are excluded from the scope of Committee D27. Development in these fields incidental to the normal work of Committee D27 will be coordinated with the appropriate technical committees of the Society.
Electrical Insulating Liquids and Gases
The promotion of knowledge pertaining to electrical insulating liquids and gases, whether of synthetic or natural origin, and the recommendation of standards pertinent to these materials. The principal materials included in this scope are oils of petroleum origin, synthetic liquids, halogenated and other gases, when used, singularly or as combinations, as electrical insulation or as an environment for electrical insulation. Standards peculiar to solid insulating materials and varnishes and the development of standards pertaining to the nonelectrical uses of liquid and gaseous materials are excluded from the scope of Committee D27. Development in these fields incidental to the normal work of Committee D27 will be coordinated with the appropriate technical committees of the Society.
General Information
SIGNIFICANCE AND USE
3.1 In most of their uses, insulating liquids are continually in contact with metals that are subject to corrosion. The presence of elemental sulfur or corrosive sulfur compounds will result in deterioration of these metals and cause conductive or high resistive films to form. The extent of deterioration is dependent upon the quantity and type of corrosive agent and time and temperature factors. Detection of these undesirable impurities, even though not in terms of quantitative values, is a means for recognizing the hazard involved.
3.2 Two methods are provided, one for copper corrosion and one for silver corrosion. Copper is slightly less sensitive to sulfur corrosion than silver but the results are easier to interpret and less prone to error. The silver corrosion procedure is provided especially for those users who have applications where the insulating liquid is in contact with a silver surface.
SCOPE
1.1 This test method describes the detection of corrosive sulfur compounds (both inorganic and organic) in electrical insulating liquids.
1.2 New and in-service insulating liquids may contain elemental sulfur or sulfur compounds, or both, that cause corrosion under certain conditions of use. This test method is designed to detect the presence of, or the propensity to form, free (elemental) sulfur and corrosive sulfur compounds by subjecting copper or silver to contact with an insulating liquid under prescribed conditions.
1.3 The values stated in SI units are to be regarded as the standard. Inch-pound units are included for informational purposes.
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.
- Standard5 pagesEnglish language
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
5.1 The primary purpose of this practice is to characterize the carbon-type composition of an oil. It is also applicable in observing the effect on oil constitution, of various refining processes such as hydrotreating, solvent extraction, and so forth. It has secondary application in relating the chemical nature of an oil to other phenomena that have been demonstrated to be related to oil composition.
5.2 Results obtained by this practice are similar to, but not identical with, results obtained from Test Method D3238. The relationship between the two and the equations used in deriving Fig. 1 are discussed in the literature.4
5.3 Although this practice tends to give consistent results, it may not compare with direct measurement test methods such as Test Method D2007.
SCOPE
1.1 This practice may be used to determine the carbon-type composition of mineral insulating oils by correlation with basic physical properties. For routine analytical purposes it eliminates the necessity for complex fractional separation and purification procedures. The practice is applicable to oils having average molecular weights from 200 to above 600, and 0 to 50 aromatic carbon atoms.
1.2 Carbon-type composition is expressed as percentage of aromatic carbons, percentage of naphthenic carbons, and percentage of paraffinic carbons. These values can be obtained from the correlation chart, Fig. 1, if both the viscosity-gravity constant (VGC) and refractivity intercept (ri) of the oil are known. Viscosity, density and relative density (specific gravity), and refractive index are the only experimental data required for use of this test method.
FIG. 1 Correlation Chart for Determining % CA, % CN, and % CP
1.3 This practice is useful for determining the carbon-type composition of electrical insulating oils of the types commonly used in electric power transformers and transmission cables. It is primarily intended for use with new oils, either inhibited or uninhibited.
1.4 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.
- Standard4 pagesEnglish language
SCOPE
1.1 This test method covers and is intended as a rapid method for the evaluation of the oxidation stability of new mineral insulating oils containing a synthetic oxidation inhibitor. This test is considered of value in checking the oxidation stability of new mineral insulating oils containing 2,6-ditertiary-butyl para-cresol or 2,6-ditertiary-butyl phenol, or both, in order to control the continuity of this property from shipment to shipment. The applicability of this procedure for use with inhibited mineral insulating oils of more than 12 cSt at 40 °C (approximately 65 SUS at 100 °F) has not been established.
1.2 The values stated in SI units are to be regarded as standard except where there is no direct equivalent for hardware designed on the inch-pound unit basis.
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. (See warning in 6.7.)
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.
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Accurate sampling, whether of the complete contents or only parts thereof, is extremely important from the standpoint of evaluating the quality of the liquid insulant sampled. Obviously, examination of a test specimen that, because of careless sampling procedure or contamination in sampling equipment, is not directly representative, leads to erroneous conclusions concerning quality and in addition results in a loss of time, effort, and expense in securing, transporting, and testing the sample.
4.2 A study of gases and moisture contained in insulating oils from transformers and other electrical power apparatus can frequently give an early indication of abnormal behavior of the apparatus, and may indicate appropriate action be taken on the equipment before it suffers greater damage. Specific gas and moisture content can be determined from oil sampled for this purpose.
SCOPE
1.1 These practices cover sampling of new electrical insulating liquids including oils, askarels, silicones, synthetic liquids, and natural ester insulating liquids as well as those insulating liquids in service or subsequent to service in cables, transformers, circuit breakers, and other electrical apparatus. These practices apply to liquids having a viscosity of less than 6.476 × 10-4 m2/s (540 cSt) at 40 °C (104 °F).
1.2 Representative samples of electrical insulating liquids are taken for test specimens so that the quality pertinent to their use may be determined. The quality in different portions of a given container, or the average quality of the whole bulk may be ascertained if desired.
1.3 The values stated in SI units are regarded as the standard where applicable. Inch pound units are used where there is no SI equivalent.
1.4 These practices also include special techniques and devices for sampling for dissolved gases-in-oil (DGA) (D3612), water (D1533) and particles (D6786).
1.5 For ease of use, this document has been indexed as follows:
Section Title
Section/Paragraph
Mandatory Conditions and General Information
Section 5
Description of Sampling Devices and Containers
Section 6, Annex A1, Appendix X2
Most Frequently Used Sampling Techniques for Electrical Apparatus
Collecting Samples from Electrical Equipment Using Bottles and Cans
Section 7, Appendix X1, Appendix X2
Collecting Samples from Electrical Equipment Using Glass Syringes (DGA and Water Analysis)
Section 8
Collecting Samples from Electrical Equipment Using Stainless Steel Cylinders (DGA and Water Analysis)
Section 9
Sampling of Cans, Drums, Tank Cars, Tank Trucks and Small Electrical Equipment
Sampling Using the Dip-Type Device (drum thief)
Section 10
Sampling Using the Pressure-Type Device
Section 11, Annex A1.1
Sampling Using the Tank Car-Type Device
Section 12, Annex A1.2
Sampling Cable Feeders
Mandatory Conditions
Section 13
General Considerations
Section 14
Sampling Using the Manifold-Type Device
Section 15, Annex A1.3
Cleaning, Preparation, Storage, and Handling of Sampling Containers
Section 16
Storage, Packaging and Shipping of Samples
Section 17
Cleaning and Storage of Sampling Devices
Section 18
Sample Information
Section 19
Mandatory Information—Construction of Sampling Devices
Annex A1
Determination of Electrical Apparatus Temperature
Appendix X1
Sample Container Types
Appendix X2
1.6 Handle askarels containing polychlorinated biphenyls (PCBs) according to federal and local regulations existing for that country. For example, the federal regulations concerning PCBs in the United States can be found in 40 CFR Part 761.
1.7 Properly contain, package and dispose of any liquid or material resulting from the use of these practices in a manner that is in accordance with local and state regulations specific to the country in w...
- Standard14 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Dissipation Factor (or Power Factor)—This is a measure of the dielectric losses in an electrical insulating liquid when used in an alternating electric field and of the energy dissipated as heat. A low dissipation factor or power factor indicates low ac dielectric losses. Dissipation factor or power factor may be useful as a means of quality control, and as an indication of changes in quality resulting from contamination and deterioration in service or as a result of handling.
4.1.1 The loss characteristic is commonly measured in terms of dissipation factor (tangent of the loss angle) or of power factor (sine of the loss angle) and may be expressed as a decimal value or as a percentage. For decimal values up to 0.05, dissipation factor and power factor values are equal to each other within about one part in one thousand. In general, since the dissipation factor or power factor of insulating oils in good condition have decimal values below 0.005, the two measurements (terms) may be considered interchangeable.
4.1.2 The exact relationship between dissipation factor (D) and power factor (PF ) is given by the following equations:
The reported value of D or PF may be expressed as a decimal value or as a percentage. For example:
4.2 Relative Permittivity (Dielectric Constant)—Insulating liquids are used in general either to insulate components of an electrical network from each other and from ground, alone or in combination with solid insulating materials, or to function as the dielectric of a capacitor. For the first use, a low value of relative permittivity is often desirable in order to have the capacitance be as small as possible, consistent with acceptable chemical and heat transfer properties. However, an intermediate value of relative permittivity may sometimes be advantageous in achieving a better voltage distribution of ac electric fields between the liquid and solid insulating materials with which the liquid may be in series. When ...
SCOPE
1.1 This test method describes testing of new electrical insulating liquids as well as liquids in service or subsequent to service in cables, transformers, oil circuit breakers, and other electrical apparatus.
1.2 This test method provides a procedure for making referee tests at a commercial frequency of between 45 Hz and 65 Hz.
1.3 Where it is desired to make routine determinations requiring less accuracy, certain modifications to this test method are permitted as described in Sections 16 to 24.
1.4 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 to determine the applicability of regulatory limitations prior to use. Specific warnings are given in 11.3.3.
1.6 Mercury has been designated by the EPA and many state agencies as a hazardous material that can cause nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for details and the EPA's website for additional information. Users should be aware that selling mercury and/or mercury containing products into your state may be prohibited by state law.
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
SIGNIFICANCE AND USE
5.1 Furanic compounds are generated by the degradation of cellulosic materials used in the solid insulation systems of electrical equipment.
5.2 Furanic compounds which are oil soluble to an appreciable degree will migrate into the insulating liquid.
5.3 High concentrations or unusual increases in the concentrations of furanic compounds in oil may indicate cellulose degradation from aging or incipient fault conditions. Testing for furanic compounds may be used to complement dissolved gas in oil analysis as performed in accordance with Test Method D3612.
SCOPE
1.1 This test method covers the determination in electrical insulating liquids of products of the degradation of cellulosic materials such as paper, pressboard, and cotton materials typically found as insulating materials in electrical equipment. These degradation products are substituted furan derivatives, commonly referred to as furanic compounds or furans. This test method allows either liquid/liquid or solid phase extraction (SPE) of the furanic compounds from the sample matrix followed by analysis for specific furanic compounds by HPLC or direct injection for analysis of specific furanic compounds by HPLC.
1.2 The individual furanic compounds that may be identified and quantified include the following:
5-hydroxymethyl-2-furaldehyde
furfuryl alcohol
2-furaldehyde
2-acetylfuran
5-methyl-2-furaldehyde
1.3 The direct injection method generally has a higher limit of detection, especially for furfuryl alcohol. Greater interference for furfuryl alcohol may be expected when using the direct injection method as opposed to extraction methods.
1.4 This test method has been used to successfully test for furanic compounds in mineral insulating oil, silicone fluid, high fire point electrical insulating oils of mineral origin, askarels, and perchloroethylene-based dielectric fluids.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Standard9 pagesEnglish language
ABSTRACT
This specification covers the requirements for sulfur hexafluoride intended for use as an electrical insulating gas. However, this specification applies only to gas as purchased. Tests for water content, acidity (hydrolyzable fluorides), noncondensable gas and carbon tetrafluoride content, and assay shall be performed and shall conform to the requirements specified.
SCOPE
1.1 This specification applies to sulfur hexafluoride for use as an electrical insulating gas.
Note 1: This specification is intended to apply only to gas as purchased. However, the test methods referred to in this standard may be useful in the evaluation of in-service or used gas. Test Method D2284 may be particularly helpful since many sulfur hexafluoride decomposition products are acidic. Test Method D2284 should not be used to evaluate the total amount of sulfur hexafluoride decomposition nor to identify contaminant species. This can only be done by gas chromatography and similar instrumental techniques.
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, 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.
- Technical specification2 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Particles in insulating oil can have a detrimental effect on the dielectric properties of the fluid, depending on the size, concentration, and nature of the particles. The source of these particles can be external contaminants, oil degradation by-products, or internal materials such as metals, carbon, or cellulose fibers.
5.2 Particle counts provide a general degree of contamination level and may be useful in assessing the condition of specific types of electrical equipment. Particle counts can also be used to determine filtering effectiveness when processing oil.
5.3 If more specific knowledge of the nature of the particles is needed, other tests such as metals analysis or fiber identification and counting must be performed.
SCOPE
1.1 This test method covers the determination of particle concentration and particle size distribution in mineral insulating oil. It is suitable for testing oils having a viscosity of 6 mm2/s to 20 mm2/s at 40 °C. The test method is specific to liquid automatic particle analyzers that use the light extinction principle.
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, 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
5.1 This test method covers the rapid determination of 12 elements in insulating oils, and it provides rapid screening of used oils for indications of wear. Test times approximate several minutes per test specimen, and detectability is in the 10 μg/kg through 100 μg/kg range.
5.2 This test method can be used to monitor equipment condition and help to define when corrective action is needed. It can also be used to detect contamination such as from silicone fluids (via Silicon) or from dirt (via Silicon and Aluminum).
5.3 This test method can be used to indicate the efficiency of reclaiming used insulating oil.
SCOPE
1.1 This test method describes the determination of metals and contaminants in insulating oils by inductively coupled plasma atomic emission spectrometry (ICP-AES). The specific elements are listed in Table 1. This test method is similar to Test Method D5185, but differs in methodology, which results in the greater sensitivity required for insulating oil applications.
1.2 This test method uses oil-soluble metals for calibration and does not purport to quantitatively determine insoluble particulates. Analytical results are particle size dependent, and low results are obtained for particles larger than several micrometers.2
1.3 This test method determines the dissolved metals (which can originate from overheating or arcing, or both) and a portion of the particulate metals (which generally originate from a wear mechanism). While this ICP method detects nearly all particles less than several micrometers, the response of larger particles decreases with increasing particle size because larger particles are less likely to make it through the nebulizer and into the sample excitation zone.
1.4 This test method includes an option for filtering the oil sample for those users who wish to separately determine dissolved metals and particulate metals (and hence, total metals).
1.5 Elements present at concentrations above the upper limit of the calibration curves can be determined with additional, appropriate dilutions and with no degradation of precision.
1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.7 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.
1.8 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
SCOPE
1.1 This specification covers rerefined previously used mineral insulating liquid of petroleum origin for reuse as an insulating and cooling medium in new and existing power and distribution electrical apparatus, such as transformers, regulators, reactors, liquid filled circuit breakers, switchgear, and attendant equipment.
1.2 This specification is intended to define a rerefined mineral insulating liquid that is functionally interchangeable and miscible with existing mineral insulating liquids, is compatible with existing apparatus, and with appropriate field maintenance2 will satisfactorily maintain its functional characteristics in its application in electrical equipment. This specification applies only to rerefined mineral insulating liquid as received prior to any processing. Liquids that undergo treatment in-situ are not covered by this specification.
1.3 Formulated rerefined mineral insulating liquids may contain additives such as inhibitors, passivators, pour point depressants, flow modifiers, gassing tendency modifiers, and other compounds. This specification will address some of these but not all. It is the responsibility of the supplier to disclose information concerning the presence of all known additives and their concentration to the user.
1.4 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.
- Technical specification6 pagesEnglish language
ABSTRACT
This specification describes a high fire-point mineral oil based electrical insulating fluid, for use as a dielectric and cooling medium in new and existing power and distribution electrical apparatuses, such as transformers and switchgear. The material discussed here is miscible with other petroleum based insulating oils, and may not be miscible with electrical insulating liquids of non-petroleum origin. The insulating oils shall be compatible with typical material of construction of existing apparatus and will satisfactorily maintain its functional characteristic in its application. This specification applies only to new insulating material oil as received prior to any processing. Sampled specimens shall undergo appropriate tests, and shall conform correspondingly to specified physical (appearance upon visual examination, color in ASTM units, fire point, flash point, aniline point, interfacial tension, pour point, relative density, and kinematic viscosity), electrical (dielectric breakdown voltage, gassing tendency, and dissipation factor), and chemical (corrosion behavior against sulfur, inorganic chlorides and sulfates content, acid number, water content, oxidation stability, oxidation inhibitor content, and PCB content) property requirements.
SCOPE
1.1 This specification describes a less flammable mineral electrical insulating liquid, for use as a dielectric and cooling medium in new and existing power and distribution electrical apparatus, such as transformers and switchgear.
1.2 Less flammable insulating liquid differs from conventional mineral insulating liquid by possessing a fire-point of at least 300 °C. This property is necessary in order to comply with certain application requirements of the National Electrical Code (Article 450-23) or other agencies. The material discussed in this specification is miscible with other petroleum based insulating liquids. Mixing less flammable liquids with lower fire point hydrocarbon insulating liquids (for example, Specification D3487 mineral liquid) may result in fire points of less than 300 °C.
1.3 This specification is intended to define a less flammable electrical mineral insulating liquid that is compatible with typical material of construction of existing apparatus and will satisfactorily maintain its functional characteristic in this application. The material described in this specification may not be miscible with electrical insulating liquids of non-petroleum origin. The user should contact the manufacturer of the less flammable insulating liquid for guidance in this respect.
1.4 This specification applies only to new electrical insulating liquid as received prior to any processing. Information on in-service maintenance testing is available in appropriate guides.2 The user should contact the manufacturers of the equipment or liquid if questions of recommended characteristics or maintenance procedures arise.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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.
- Technical specification3 pagesEnglish language
- Technical specification3 pagesEnglish language
SCOPE
1.1 This specification covers less-flammable (high fire point) synthetic ester insulating liquids for use as a dielectric and cooling in new and existing electrical power apparatus including power and distribution transformers, switchgear, and other associated equipment
1.2 Synthetic ester insulating liquids differ from conventional mineral oil and other less-flammable (high fire point) liquids in that they are products derived from the chemical reaction, processing, and physical treatments of a carboxylic acid and an alcohol.
1.3 This specification is intended to define synthetic ester electrical insulating liquids that are compatible with typical materials of construction of existing apparatus and are expected to maintain their functional characteristics in these applications. The material described in this specification is not always miscible with other electrical insulating liquids. The user should contact the manufacturer of the synthetic ester insulating liquid for guidance in this respect.
1.4 This specification applies only to unused synthetic ester insulating liquids as received prior to any processing. The user should contact the manufacturer of the equipment or liquid, or both, if questions of recommended characteristics or liquid maintenance procedures arise.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Technical specification4 pagesEnglish language
SIGNIFICANCE AND USE
4.1 By use of this test method and Test Methods D1500 or D2129 the color and condition of a test specimen of electrical insulating liquid may be estimated during a field inspection, thus assisting in the decision as to whether or not the sample should be sent to a central laboratory for full evaluation. Cloudiness, particles of insulation, products of metal corrosion, or other undesirable suspended materials, as well as any unusual change in color may be detected.
SCOPE
1.1 This test method for visual examination is applicable to electrical insulating liquids that have been used in transformers, oil circuit breakers, or other electrical apparatus as insulating or cooling media, or both.
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.
- Standard2 pagesEnglish language
ABSTRACT
This guide describes methods of testing and specifications for electrical insulating oils of petroleum origin intended for use in electrical cables, transformers, oil circuit breakers, and other electrical apparatus where the oils are used as insulating, or heat transfer media, or both. This guide is classified into the following categories: sampling practices, physical tests, electrical tests, chemical tests, and specifications. The test methods shall be as follows: aniline point; coefficient of thermal expansion; color; examination; flash and fire point; interfacial tension; pour point of petroleum products; refractive index; relative density; specific heat; thermal conductivity; turbidity; viscosity; dielectric breakdown voltage; dissipation factor and relative permittivity; gassing tendency; resistivity; stability under electrical discharge; acidity; carbon-type composition; compatibility with construction material; copper content; furanic compounds; gas analysis; gas content; inorganic chlorides and sulfates; neutralization numbers; oxidation inhibitor content; oxidation stability; polychlorinated biphenyl content; sediment and soluble sludge; sulfur; water content; mineral insulating oil for electrical apparatus; and high firepoint electrical insulating oils.
SCOPE
1.1 This guide describes methods of testing and specifications for electrical insulating liquids intended for use in electrical cables, transformers, liquid-filled circuit breakers, and other electrical apparatus where the liquids are used as insulating, or heat transfer media, or both.
1.2 The purpose of this guide is to outline the applicability of the available test methods. Where more than one is available for measuring a given property, their relative advantages are described, along with an indication of laboratory convenience, precision, (95 % confidence limits), and applicability to specific types of electrical insulating liquids.
1.3 This guide is classified into the following categories: Sampling Practices, Physical Tests, Electrical Tests, Chemical Tests, and Specifications. Within each test category, the test methods are listed alphabetically by property measured. A list of standards follows:
Category
Section
ASTM Standard
Sampling:
3
D923
Physical Tests:
Aniline Point
4
D611
Coefficient of Thermal Ex-
pansion
5
D1903
Color
6
D1500
Examination: Visual Infrared
7
D1524, D2144, D2129
Flash and Fire Point
8
D92
Interfacial Tension
9
D971
Pour Point of Petroleum
Products
10
D97, D5949, D5950
Particle Count in Mineral
Insulating Oil
11
D6786
Refractive Index and Specific
Optical Dispersion
12
D1218
Relative Density (Specific
Gravity)
13
D287, D1217, D1298, D1481, D4052
Specific Heat
14
D2766
Thermal Conductivity
15
D2717
Viscosity
16
D445, D2161, D7042
Electrical Tests:
Dielectric Breakdown Voltage
17
D877, D1816, D3300
Dissipation Factor and Rela-
tive Permittivity (Dielectric
Constant)
18
D924
Gassing Characteristic
Under Thermal Stress
19
D7150
Gassing Tendency
20
D2300
Resistivity
21
D1169
Chemical Tests:
Acidity, Approximate
22
D1534
Carbon-Type Composition
23
D2140
Compatibility with Construc-
tion Material
24
D3455
Copper Content
25
D3635
Elements by Inductively
Coupled Plasma (ICP-AES)
26
D7151
Furanic Compounds in
Electrical Insulating Liquids
27
D5837
Dissolved Gas Analysis
28
D3612
Gas Content of Cable and
Capacitor Liquids
29
D831, D1827, D2945
Neutralization (Acid and
Base) Numbers
30
D664, D974
Oxidation Inhibitor Content
31
D2668, D4768
Oxidation Stability
32
D1934, D2112, D2440
P...
- Guide16 pagesEnglish language
- Guide16 pagesEnglish language
SIGNIFICANCE AND USE
3.1 The quantitative determination of 2,6-ditertiary-butyl paracresol and 2,6-ditertiary-butyl phenol in a new electrical insulating oil measures the amount of this material that has been added to the oil as protection against oxidation. In a used oil it measures the amount remaining after oxidation has reduced its concentration. The test is also suitable for manufacturing control and specification acceptance.
3.2 When an infrared spectrum is obtained of an electrical insulating oil inhibited with either of these compounds there is an increase in absorbance of the spectrum at several wavelengths (or wavenumbers). 2,6 ditertiary-butyl paracresol produces pronounced increases in absorbance at 2.72 μm (3650 cm−1), and 11.63 μm (860 cm−1 ). 2,6 ditertiary-butyl phenol produces pronounced increases in absorbance at 2.72 μm (3650 cm−1) and 13.42 μm (745 cm −1).
3.3 When making this test on other than a highly oxidized oil or when using a double-beam spectrophotometer, it has been found convenient to obtain the spectrum between 2.5 μm (4000 cm−1) and 2.9 μm (3450 cm−1) because the instrument is compensated for the presence of moisture and the band is not influenced by intermolecular forces (associations). However, when testing a highly oxidized oil or when using a single-beam instrument better results may be obtained if the scan is made between 10.90 μm (918 cm−1) and 14.00 μm (714 cm−1).
3.4 Increased absorption at 11.63 μm (860 cm −1) or 13.42 μm (745 cm−1) or both, will identify the inhibitor as 2,6-ditertiary-butyl paracresol or 2,6-ditertiary-butyl phenol respectively (Note 1).
Note 1: The absorbance at 745 cm−1 for 2,6-ditertiary-butyl phenol and at 860 cm−1 for 2,6-ditertiary-butyl paracresol for equal concentrations will be in the approximate ratio of 2.6 to 1.
SCOPE
1.1 This test method covers the determination of the weight percent of 2,6-ditertiary-butyl paracresol (DBPC) and 2,6-ditertiary-butyl phenol (DBP) in new or used electrical insulating oil in concentrations up to 0.5 % by measuring its absorbance at the specified wavelengths in the infrared spectrum.
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, 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.
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
5.1 The infrared spectrum of an electrical insulating oil is a record of the absorption of infrared energy over a range of wavelengths. The spectrum indicates the general chemical composition of the test specimen.
Note 2: The infrared spectrum of a pure chemical compound is probably the most characteristic property of that compound. However, in the case of oils, multicomponent systems are being examined whose spectra are the sum total of all the spectra of the individual components. Because the absorption bands of the components may overlap, the spectrum of the oil is not as sharply defined as that for a single compound. For these reasons, these practices may not in every case be suitable for the quantitative estimation of the components of such a complex mixture as mineral oil.
SCOPE
1.1 These practices are to be used for the recording and interpretation of infrared absorption spectra of electrical insulating oils from 4000 cm−1 to 400 cm−1 (2.5 μm to 25 μm).
Note 1: While these practices are specific to ratio recording or optical null double-beam dispersive spectrophotometers, single-beam and HATR (horizontal attenuated total reflectance), Fourier-transform rapid scan infrared spectrophotometers may also be used. By computerized subtraction techniques, ratio methods can be used. Any of these types of equipment may be suitable if they comply with the specifications described in Practice E932.
1.2 Two practices are covered, a Reference Standard Practice and a Differential Practice.
1.3 These practices are designed primarily for use as rapid continuity tests for identifying a shipment of oil from a supplier by comparing its spectrum with that obtained from previous shipments, or with the sample on which approval tests were made. They also may be used for the detection of certain types of contamination in oils, and for the identification of oils in storage or service, by comparison of the spectra of the unknown and known oils. The practices are not intended for the determination of the various constituents of an oil.
1.4 Warning—Infrared absorption is a tool of high resolving power. Conclusions as to continuity of oil quality should not be drawn until sufficient data have been accumulated so that the shipment-to-shipment variation is clearly established, for example.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Electrical insulating oil may contain small amounts of dissolved metals derived either directly from the base oil or from contact with metals during refining or service. When copper is present, it acts as a catalyst in promoting oxidation of the oil. This test method is useful for research for new oils and to assess the condition of service-aged oils. Consideration should be given to the limits of detection outlined in the scope.
SCOPE
1.1 This test method covers the determination of copper in new or used electrical insulating oil of petroleum origin by atomic absorption spectrophotometry.
1.2 The lowest limit of detectability is primarily dependent upon the method of atomization, but also upon the energy source, the fuel and oxidant, and the degree of electrical expansion of the output signal. The lowest detectable concentration is usually considered to be equal to twice the maximum variation of the background. For flame atomization, the lower limit of detectability is generally in the order of 0.1 ppm or 0.1 mg/kg. For non-flame atomization, the lower limit of detectability is less than 0.01 ppm.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The oxidation stability test of mineral transformer oils is a method for assessing the amount of sludge and acid products formed in a transformer oil when the oil is tested under prescribed conditions. Good oxidation stability is necessary in order to maximize the service life of the oil by minimizing the formation of sludge and acid. Oils that meet the requirements specified for this test in Specification D3487 tend to minimize electrical conduction, ensure acceptable heat transfer, and preserve system life. There is no proven correlation between performance in this test and performance in service, since the test does not model the whole insulation system (oil, paper, enamel, wire). However, the test can be used as a control test for evaluating oxidation inhibitors and to check the consistency of oxidation stability of production oils.
SCOPE
1.1 This test method determines the resistance of mineral transformer oils to oxidation under prescribed accelerated aging conditions. Oxidation stability is measured by the propensity of oils to form sludge and acid products during oxidation. This test method is applicable to new oils, both uninhibited and inhibited, but is not well defined for used or reclaimed oils.
Note 1: A shorter duration oxidation test for evaluation of inhibited oils is available in Test Method D2112.
Note 2: For those interested in the measurement of volatile acidity, reference is made to IEC Method 61125. 2
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, 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.
- Standard5 pagesEnglish language
- Standard7 pagesEnglish language
- Standard7 pagesEnglish language
ABSTRACT
This specification applies to Type I gaseous air, both atmospheric and that synthesized by blending oxygen and nitrogen in proper proportions, used as an electrical insulating material in electrical equipment. Appropriately sampled specimens shall undergo tests and should adhere accordingly to chemical requirements as to dew point, and specified compositions for oxygen, carbon monoxide, carbon dioxide, and nitrogen.
SCOPE
1.1 This specification applies to air used as an electrical insulating material in electrical equipment.
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.
- Technical specification2 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Methanol and ethanol are generated by the degradation of cellulosic materials used in the solid insulation systems of electrical equipment. More particularly, methanol comes from the depolymerization of cellulosic materials.3, 4, 5, 6
5.2 Methanol and ethanol, which are soluble in an insulating liquid to an appreciable degree, will proportionally migrate to that liquid after being produced from the cellulose.
5.3 High concentrations or unusual increases in the concentrations of methanol or ethanol, or both, in an insulating liquid may indicate cellulose degradation from aging or incipient fault conditions. Testing for these alcohols may be used to complement dissolved gas-in-oil analysis and furanic compounds as performed in accordance with Test Methods D3612 and D5837 respectively.
SCOPE
1.1 This test method describes the determination of by-products of cellulosic materials degradation found in electrical insulation systems that are immersed in insulating liquid. Such materials include paper, pressboard, wood and cotton materials. This test method allows the analysis of methanol and ethanol from the sample matrix by headspace GC-MS or GC-FID.
1.2 This test method has been used to test for methanol and ethanol in mineral insulating liquids and less flammable electrical insulating liquids of mineral origin as defined in D3487 and D5222 respectively. Currently, this method is not a practical application for ester liquids.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Open-beaker oxidative aging methods have been used for many years in laboratories of insulating liquid companies, electrical equipment manufacturers, and electric utility companies interested in the stability of electrical insulating liquids under oxidative conditions. They are particularly useful as a check on the continuity of production and shipment of insulating liquids. They are also useful as process and product checks for applicable type insulating liquids.
5.2 Specification limits for insulating liquids subjected to open-beaker oxidative aging by this method are established by agreement between individual producers and consumers of applicable type insulating liquids. These properties of the insulating liquid involved in specification limits for aging stability may be measured after the oxidative aging (and sometimes before aging) by appropriate test methods such as Test Methods D924, D971, D1169, and D974 or D664. Other test methods such as D445 can be used when deemed appropriate.
SCOPE
1.1 This test method covers two procedures for subjecting electrical insulating liquids to oxidative aging:
1.1.1 Procedure A, without a metal catalyst, and
1.1.2 Procedure B, with a metal catalyst.
1.2 This test method is applicable to insulating liquids used as impregnating or pressure media in electrical power transmission cables if less than 10 % of the insulating liquid evaporates during the aging procedures. It applies and is generally useful primarily in the evaluation and quality control of unused insulating liquids, either inhibited or uninhibited.
1.3 This test method is applicable to study the long-term behavior of an insulating liquid being considered for free breathing transformers. An unsealed vessel aging procedure, in presence of air or oxygen, allows greatly increased oxidation rate of the liquid. This procedure is rapid and provides a controlled thermal stress assessment.
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.5 An open beaked test shall only be carried out on liquids with flash points at or above 130°C or 15°C above the oven temperature. 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 7.5 for a specific warning statement.
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.
- Standard3 pagesEnglish language
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The gas content of cable and capacitor oils is considered to be important, since the evolution of gas in the form of bubbles can have an adverse effect on the insulating properties of these fluids. It is customary to degas these oils prior to use, and this test method provides a means of determining the gas content before and after degassing.
SCOPE
1.1 This test method covers the determination of the gas content of electrical insulating oils of low and medium viscosities in the general range up to 190 mm2/s at 104°F [40°C], such as are used in capacitors and paper-insulated electric cables and cable systems of the oil-filled type. The determination of gas content is desirable for any insulating oil having these properties and intended for use in a degassed state.
Note 1: For testing insulating oils with viscosities of 19 mm2/s or below at 40°C, see Test Method D2945.
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 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.
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
5.1 Generation of combustible gases is used to determine the condition of oil-filled electrical apparatus. Many years of empirical evidence has yielded guidelines such as those given in IEEE C57.104, IEC 60599 and IEC 61464. Industry experience has shown that electric and thermal faults in oil-filled electrical apparatus are the usual sources that generate gases. Experience has shown that some of the gases could form in the oil due to thermal stress or as a result of contamination, without any other influences.
5.2 Some transformer oils subjected to thermal stress and oils that contain certain types of contamination may produce specific gases at lower temperatures than normally expected for their generation and hence, falsely indicate abnormal operation of the electrical apparatus. Some new oils have produced large amounts of gases, especially hydrogen, without the influence of other electrical apparatus materials or electrical stresses. This renders interpretation of the dissolved gas analysis more complicated.
5.3 Heating for 164 h has been found to be sufficient to reach a stable and characteristic gassing pattern.
5.4 This method uses both dry air and dry nitrogen as the sparging gas. This is to reflect either an electrical apparatus preservation system that allows oxygen to contact the oil or one that is sealed from the outside atmosphere. Oils sparged with air generally produce much more hydrogen as a percentage of the total combustible gas content as compared to oils sparged with nitrogen as these produce more hydrocarbons in relation to hydrogen.
SCOPE
1.1 This test method describes the procedures to determine the gassing characteristics due to thermal stress at 120°C of insulating liquids specifically and without the influence of other electrical apparatus materials or electrical stresses. This test method was primarily designed for insulating mineral oil. It can be applied to other insulating liquids in which dissolved gas-in-oil analysis (Test Method D3612) is commonly performed.
1.2 This test method is particularly suited for detection of the phenomenon sometimes known as “stray gassing” and is also referred to in CIGRE TF11 B39.
1.3 This test method is performed on transformer insulating liquids to determine the propensity of the oil to produce certain gases such as hydrogen and hydrocarbons at low temperatures.
1.4 This test method details two procedures:
1.5 Method A describes the procedure for determining the gassing characteristics of insulating liquids, at 120°C for 164 h.
1.6 Method B describes the procedure for processing the insulating liquid through an attapulgite clay column to remove organic contaminants and other reactive groups that may influence the gassing behavior of an insulating liquid, which is suspected of being contaminated. This procedure applies to both new and used insulating liquids.
1.7 The values stated in SI units are to be regarded as standard. English units are used when there is no metric equivalent.
1.8 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.
1.9 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 Knowledge of gas solubility is of extreme importance in the lubrication of gas compressors. It is believed to be a substantial factor in boundary lubrication, where the sudden release of dissolved gas may cause cavitation erosion, or even collapse of the fluid film. In hydraulic and seal oils, gas dissolved at high pressure can cause excessive foaming on release of the pressure. In aviation oils and fuels, the difference in pressure between take-off and cruise altitude can cause foaming out of the storage vessels and interrupt flow to the pumps.
SCOPE
1.1 This test method covers the estimation of the equilibrium solubility of several common gases encountered in the aerospace industry in hydrocarbon liquids. These include petroleum fractions with densities in the range from 0.63 to 0.90 at 288 K (59°F). The solubilities can be estimated over the temperature range 228 K (−50°F) to 423 K (302°F).
1.2 This test method is based on the Clausius-Clapeyron equation, Henry's law, and the perfect gas law, with empirically assigned constants for the variation with density and for each gas.
1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
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.
- Standard4 pagesEnglish language
ABSTRACT
This specification covers silicone fluid, polydimethylsiloxane, for use in transformers, capacitors, and electronic assemblies as an insulating or cooling medium, or both. Physical, electrical, and chemical tests shall be conducted on the specimen to check for quality conformance. The silicone fluid shall conform to the color, flash point, fire point, pour point, refractive index, viscosity, specific gravity, weight of volatile matter, dielectric breakdown, disk electrodes, VDE electrodes, dissipation factor, volume resistivity, neutralization number, water content, and PCB content requirements.
SCOPE
1.1 This specification covers silicone liquid for use in transformers, capacitors, and electronic assemblies as an insulating or cooling medium, or both.
1.2 Silicone liquid covered by this specification is polydimethylsiloxane having a nominal viscosity of 50 mm2/s at 25°C and a fire point of 340°C or greater. This specification applies only to new silicone liquid. Information on in-service maintenance testing is available in appropriate guides.2
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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.
- Technical specification2 pagesEnglish language
- Technical specification2 pagesEnglish language
SIGNIFICANCE AND USE
3.1 This test method is most commonly performed using a negative polarity needle or a sharp defined point to an opposing grounded sphere (NPS). The NPS breakdown voltage of fresh unused liquids measured in the highly divergent field in this configuration depends on the insulating liquid composition, decreasing with increasing concentration of aromatic, particularly polyaromatic, hydrocarbon molecules in liquids of petroleum origin and decreasing with ester molecular structure, either natural or synthetic.
3.2 This test method may be used to evaluate the continuity of composition of an insulating liquid from shipment to shipment. The NPS impulse breakdown voltage of an insulating liquid can also be substantially lowered by contact with materials of construction, by service aging, particulate matter, and by other impurities. Test results lower than those expected for a given fresh liquid may also indicate use or contamination.
3.3 Although polarity of the voltage wave has little or no effect on the breakdown strength of an insulating liquid in uniform fields, polarity does have a marked effect on the breakdown voltage in nonuniform electric fields.
3.4 Transient voltages may also vary over a wide range in both the time to reach crest value and the time to decay to half crest or to zero magnitude. The IEEE standard lightning impulse test (see 2.2) specifies a 1.2 by 50-μs negative polarity wave.
SCOPE
1.1 This test method covers the determination of the dielectric breakdown voltage of insulating liquids in a highly divergent field under impulse conditions and has been found applicable to liquids of petroleum origin, natural and synthetic esters.
1.2 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.
1.3 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.
- Standard4 pagesEnglish language
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
3.1 The magnitude of the changes in the electrical properties of the silicone fluid is of importance in determining the contamination of the fluid by the test specimen.
3.2 Physical and chemical changes in the fluid, such as color and acidity, also indicate solubility or other adverse effects of the test specimen on the fluid.
3.3 Physical changes of the test specimen, such as hardness, swelling, and discoloration, show the effect of the fluid on the test specimen and are used to determine the suitability of the material for use in silicone fluid.
3.4 A material meeting the criteria recommended does not necessarily indicate suitability for use in electrical equipment. Other properties must also be considered. Additionally, certain materials containing additives may meet the requirements of these test methods yet be unsatisfactory when subjected to longer-term evaluations.
3.5 These test methods may be used as a guide for testing the compatibility of materials for silicone fluids other than 50 cSt poly-dimethyl siloxane fluid, but different criteria for judgment may be necessary.
SCOPE
1.1 These test methods cover screening for the compatibility of construction materials with silicone fluid for use in electrical equipment.
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, 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Tests covered in this standard may be used for quality control and design considerations.
4.2 Included in each test method is a brief statement describing its significance.
SCOPE
1.1 These test methods cover the testing of silicone liquids for use in transformers, capacitors, and electronic assemblies as an insulating or cooling medium, or both. These methods are generally suitable for specification acceptance (Specification D4652), factory control, referee testing, and research.
1.2 Although some of the test methods listed here apply primarily to petroleum-based fluids, they are, with minor revisions, equally applicable to silicone liquids.
1.3 Silicone liquids are used for electrical insulating purposes because of their stable properties at high and low temperatures and their relative environmental inertness.
1.4 A list of the properties and standards are as follows:
Property Measured
Section
ASTM Test Method
Physical:
Color
6
D2129
Flash point
7
D92
Fire point
7
D92
Polychlorinated biphenyl
content
8
D4059
Pour point
9
D97
Refractive index
10
D1807
Specific gravity
11
D1298, D1481, D4052
Volatility
12
D4559
Viscosity
13
D445
Chemical:
Acid number
14
D974
Water content
15
D1533
Electrical:
Relative permittivity
16
D9242
Dielectric breakdown
voltage
17
D8773
Dielectric breakdown
voltage
17
D1816
Dissipation factor
18
D9242
Specific resistance
19
D11692
Compatibility
20
D5282
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.
- Standard4 pagesEnglish language
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The dielectric breakdown voltage and dielectric strength of an insulating gas in a uniform field depends primarily on the molecular structure of the gas. As different gases are mixed either by plan or by contamination, any change in dielectric breakdown voltage and dielectric strength will depend on both the nature and proportion of the individual gases. This test method uses plane and spherical electrodes which provide a nearly uniform field (see Appendix) in the area of electrical discharge. It is suitable for determining the dielectric breakdown voltage and dielectric strength of different gases and mixtures thereof for research and application evaluations and also as a field test. A more complete discussion of the significance of the dielectric strength test is given in the Appendix.
SCOPE
1.1 This test method covers the determination of the dielectric breakdown voltage and dielectric strength of insulating gases used in transformers, circuit breakers, cables, and similar apparatus as an insulating medium. The test method is applicable only to gases with boiling points below room temperature at atmospheric pressure.
1.2 This standard may involve hazardous materials, operations, and equipment. 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 Mercury has been designated by EPA and many state agencies as a hazardous material that can cause central nervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Material Safety Data Sheet (MSDS) for details and EPA's website — http://www.epa.gov/mercury/faq.htm for additional information. Users should be aware that selling mercury and/or mercury containing products into your state may be prohibited by state law.
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.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Electrical characteristics of an insulating liquid may be affected deleteriously by excessive water content. A high water content may make a dielectric liquid unsuitable for some electrical applications due to deterioration of properties such as the dielectric breakdown voltage.
4.2 This test is suitable for use in acceptance specifications, in control of processing, and in evaluating the condition of dielectric liquids in service.
SCOPE
1.1 This test method covers the measurement of water present in insulating liquids by coulometric Karl Fischer titration. This test method is used commonly for test specimens below 100 % relative saturation of water in oil. The coulometric test method is known for its high degree of sensitivity (typically 10 μg H2O). This test method requires the use of equipment specifically designed for coulometric titration.
1.2 This test method recommends the use of commercially available coulometric Karl Fischer titrators and reagents.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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. For specific precautionary statements see 8.1 and A2.1.
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 Knowledge of gas solubility is of extreme importance in the lubrication of gas compressors. It is believed to be a substantial factor in boundary lubrication, where the sudden release of dissolved gas may cause cavitation erosion, or even collapse of the fluid film. In hydraulic and seal oils, gas dissolved at high pressure can cause excessive foaming on release of the pressure. In aviation oils and fuels, the difference in pressure between take-off and cruise altitude can cause foaming in storage vessels and interrupt flow to pumps.
SCOPE
1.1 This test method covers a procedure for estimating the equilibrium solubility of several common gases in petroleum and synthetic lubricants, fuels, and solvents, at temperatures between 0 and 488 K.
1.2 This test method is limited to systems in which polarity and hydrogen bonding are not strong enough to cause serious deviations from regularity. Specifically excluded are such gases as HCl, NH3, and SO2, and hydroxy liquids such as alcohols, glycols, and water. Estimating the solubility of CO2 in nonhydrocarbons is also specifically excluded.
1.3 Highly aromatic oils such as diphenoxy phenylene ethers violate the stated accuracy above 363 K, at which point the estimate for nitrogen solubility is 43 % higher than the observation.
1.4 Lubricants are given preference in this test method to the extent that certain empirical factors were adjusted to the lubricant data. Estimates for distillate fuels are made from the lubricant estimates by a further set of empirical factors, and are less accurate. Estimates for halogenated solvents are made as if they were hydrocarbons, and are the least accurate of the three.
1.5 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
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.
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Interfacial tension measurements on electrical insulating liquids provide a sensitive means of detecting small amounts of soluble polar contaminants and products of oxidation. A high value for new mineral insulating oil indicates the absence of most undesirable polar contaminants. The test is frequently applied to service-aged mineral oils as an indication of the degree of deterioration.
Note 1: Different liquid matrixes are reviewed in Appendix X1.
SCOPE
1.1 This test method covers the measurement of the interfacial tension between insulating liquid that has a relative density (specific gravity) less than water and water, under non-equilibrium conditions.
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. See 7.2 for a specific warning statement.
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
- Standard4 pagesEnglish language
SIGNIFICANCE AND USE
4.1 In new electrical insulating oil, this test method provides a quantitative measure of the amounts of 2,6-ditertiary-butyl para-cresol and 2,6-ditertiary-butyl phenol that have been added to the oil. In a used oil, the test measures the amount of these inhibitors remaining in the oil. This test method is suitable for manufacturing control, specification acceptance, and service evaluation.
4.2 This test method is used to separate, identify, and quantify the inhibitors with minimal interference and matrix effects.
4.3 This test method has also been used successfully to determine the inhibitor concentrations in other insulating liquids such as esters and high-temperature hydrocarbons.
SCOPE
1.1 This test method covers the determination by gas chromatography of 2,6-ditertiary-butyl para-cresol and 2,6-ditertiary-butyl phenol in new and used insulating liquids at concentrations up to 0.5 %. It includes the determination in Type I and II insulating mineral oils as specified in Specification D3487, but has also been used to measure these inhibitors in other insulating liquids, such as esters and high fire-point hydrocarbons.
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
4.1 Acidic fluorides are undesirable in SF6 used as an electrical insulating gas in that they may contribute to corrosion or constitute dielectric hazard.
4.2 This test method is valid for both new and used SF6. In used SF6, it will only measure those active species which are hydrolyzable.
SCOPE
1.1 This test method covers the determination of the acidic fluorides of sulfur hexafluoride (SF6).
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, 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Arcing, partial discharge, and localized overheating in the insulation system of transformers result in chemical decomposition of the insulating oil and other insulating materials. This may generate various gases, some of which are combustible. Typically, gases are generated in the oil and then partitioned into the gas space according to their individual solubilities. Gases which are highly oil-soluble, such as acetylene, may not be in significant quantities in the gas space until an incipient fault has progressed to a very serious condition or failure of the transformer. Gases such as carbon monoxide and hydrogen which have low solubilities in oil can make up a large fraction of the combustible gases in the gas space. Detection of these gases is frequently the first available indication of a malfunction. Portable combustible gas meters are a convenient means of detecting the presence of generated gases.
4.2 Normal operation of a transformer may result in the formation of some combustible gases. The detection of an incipient fault by this method involves an evaluation of the amount of combustible gases present, the rate of generation of these gases, and their rate of escape from the transformer. Refer to IEEE C57.104 for detailed information on interpretation of gassing in transformers.
SCOPE
1.1 This field practice covers the detection and estimation of combustible gases in the gas blanket above the oil or in gas detector relays in transformers using portable instruments. It is applicable only with transformers using mineral oil as the dielectric fluid. Gases dissolved in the oil and noncombustible gases are not determined. A method of calibrating the instruments with a known gas mixture is included.
1.2 This practice affords a semi-quantitative estimate of the total combustible gases present in a gas mixture. If a more accurate determination of the total amount of combustible gases or a quantitative determination of the individual components is desired, use a laboratory analytical method, such as Test Method D3612.
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. Specific precautionary statements are given in 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
3.1 The magnitude of the changes in the electrical properties of the insulating oil are of importance in determining the contamination of the oil by the test specimen.
3.2 Physical and chemical changes in the oil such as color, interfacial tension and acidity, also indicate solubility or other adverse effects of the test specimen on the oil.
3.3 Physical changes of the test specimen such as hardness, swelling, and discoloration show the effect of the oil on the test specimen and are used to determine the suitability of the material for use in insulating oil.
3.4 A material meeting the criteria recommended does not necessarily indicate suitability for use in electrical equipment. Other properties must also be considered. Additionally, certain materials containing additives may meet the requirements of these test methods, yet be unsatisfactory when subjected to longer term evaluations. Examples of such materials are polyvinyl chloride (PVC) based compounds, nylon and elastomeric compounds.
SCOPE
1.1 These test methods cover screening for the compatibility of materials of construction with electrical insulating oil for use in electrical equipment.
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, 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
3.1 The dielectric breakdown voltage is a measure of the ability of an insulating liquid to withstand electrical stress. The power-frequency breakdown voltage of a liquid is reduced by the presence of contaminants such as cellulosic fibers, conducting particles, dirt, and water. A low result in this test method indicates the presence of significant concentrations of one or more of these contaminants in the liquid tested. See Appendix X1.
3.2 A high breakdown voltage measured in this test method does not necessarily indicate that the amount of the contaminants present in a liquid from which the sample was taken is sufficiently low for the sampled liquid to be acceptable in all electrical equipment. Test Method D877 is not sensitive to low levels of these contaminants. Breakdown in this test method is dominated by events occurring at the electrode edges. The voltage stress distribution between the parallel disk electrodes used in this test method are quasi-uniform and there is substantial stress concentration at the sharp edges of the flat disk faces.
3.3 This test method may be used for evaluation of insulating liquids in equipment that is designed to be filled with unprocessed liquids as delivered by a vendor.
3.4 This test method is not recommended for evaluation of the breakdown voltage of liquids used in equipment that requires the application of vacuum and filtering of the oil before being placed into service. Test Method D1816 should be used to determine the breakdown voltage of filtered and degassed liquids.
3.5 This test method is used in laboratory or field tests. For field breakdown results to be comparable to laboratory results, all criteria including room temperature (20 to 30 °C) must be met.
SCOPE
1.1 This test method describes two procedures, A and B, for determining the electrical breakdown voltage of insulating liquid specimens. The breakdown test uses ac voltage in the power-frequency range from 45 to 65 Hz.
1.2 This test method is used to determine the electrical discharge voltage of in-use electrical liquids. It is no longer applicable to new insulating liquids upon receipt, in which case Test Method D1816 shall be used.
Note 1: It is understood that long-term histories for this test method exist, but this test method is no longer considered applicable as numerous deficits exist that affect its usefulness. It is recommended to move all new and in-service electrical discharge voltage testing of electrical insulating liquids to Test Method D1816.
1.3 Limitations of the Procedures:
1.3.1 The sensitivity of this test method to the general population of contaminants present in a liquid sample decreases as applied test voltages used in this test method become greater than approximately 25 kV rms.
1.3.2 If the concentration of water in the sample at room temperature is less than 60 % of saturation, the sensitivity of this test method to the presence of water is decreased. For further information refer to RR:D27-1006.2
1.3.3 The suitability for this test method has not been determined for a liquid's viscosity higher than 900 cSt at 40 °C.
1.4 Procedure Applications
1.4.1 Procedure A:
1.4.1.1 Procedure A is used to determine the breakdown voltage of liquids in which any insoluble breakdown products easily settle during the interval between the required repeated breakdown tests. These liquids include petroleum oils, hydrocarbons, natural and synthetic esters, and askarels (PCB) used as insulating and cooling liquids in transformers, cables, and similar apparatus.
1.4.1.2 Procedure A may be used to obtain the dielectric breakdown of silicone fluid as specified in Test Methods D2225, provided the discharge energy into the sample is less than 20 mJ (milli joule) per breakdown for five consecutive breakdowns.
1.4.2 Procedure B:
1.4.2.1 This procedure is used to determine the breakdown voltage of liquids in which any insoluble breakdown pro...
- Standard6 pagesEnglish language
- Standard6 pagesEnglish language
SIGNIFICANCE AND USE
3.1 The dielectric breakdown voltage of an insulating liquid is of importance as a measure of the liquid's ability to withstand electric stress without failure. The dielectric breakdown voltage serves to indicate the presence of contaminating agents such as water, dirt, cellulosic fibers, or conducting particles in the liquid, one or more of which may be present in significant concentrations when low breakdown voltages are obtained. However, a high dielectric breakdown voltage does not necessarily indicate the absence of all contaminants; it may merely indicate that the concentrations of contaminants that are present in the liquid between the electrodes are not large enough to deleteriously affect the average breakdown voltage of the liquid when tested by this test method (see Appendix X1.)
3.2 This test method is used in laboratory or field tests. For field breakdown results to be comparable to laboratory results, all criteria including room temperature (20 to 30 °C) must be met.
SCOPE
1.1 This test method covers the determination of the dielectric breakdown voltage of insulating liquids (oils of petroleum origin, silicone fluids, high fire-point mineral electrical insulating oils, synthetic ester fluids and natural ester fluids). This test method is applicable to insulating liquids commonly used in cables, transformers, oil circuit breakers, and similar apparatus as an insulating and cooling medium. Refer to Terminology D2864 for definitions used in this test method.
1.2 This test method is sensitive to the deleterious effects of moisture in solution especially when cellulosic fibers are present in the liquid. It has been found to be especially useful in diagnostic and laboratory investigations of the dielectric breakdown strength of insulating liquid in insulating systems.2
1.3 This test method is used to judge if the VDE electrode breakdown voltage requirements are met for insulating liquids. This test method should be used as recommended by professional organization standards such as IEEE C57.106.
1.4 This test method may be used to obtain the dielectric breakdown of silicone fluid as specified in Test Method D2225, Specification D4652, or Specification D6871, provided that the discharge energy into the sample is less than 20 mJ (milli joule) per breakdown for five consecutive breakdowns.
1.5 Both the metric and the alternative inch-pound units are acceptable.
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.
- Standard5 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The resistivity of a liquid is a measure of its electrical insulating properties under conditions comparable to those of the test. High resistivity reflects low content of free ions and ion-forming particles, and normally indicates a low concentration of conductive contaminants.
SCOPE
1.1 This test method covers the determination of specific resistance (resistivity) applied to new electrical insulating liquids, as well as to liquids in service, or subsequent to service, in cables, transformers, circuit breakers, and other electrical apparatus.
1.2 This test method covers a procedure for making referee tests with dc potential.
1.3 When it is desired to make routine determinations requiring less accuracy, certain modifications to this test method are permitted as described in Sections 19 – 26.
1.4 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. See 17.4.3 for a specific warning statement.
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
4.1 Air and carbon tetrafluoride (CF4) are two contaminants of interest in sulfur hexafluoride (SF6). Both of these contaminants adversely affect the performance of SF6 when used as an electrical insulating gas. Specification for maximum levels of these contaminants are given in Specification D2472.
4.2 Gas chromatography is used to separate these contaminants from a sample of SF6 and to determine their concentration.
SCOPE
1.1 This test method covers the determination of air (Note 1) and carbon tetrafluoride as impurities in sulfur hexafluoride.
Note 1: Nitrogen, oxygen, or any of their mixtures is considered to be air. Commercial grade air or nitrogen is used for standardization.
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, 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.
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
5.1 United States governmental regulations mandate that electrical apparatus and electrical insulating fluids containing PCB be handled and disposed of through specific procedures. The procedure to be used for a particular apparatus or quantity of insulating fluid is determined by the PCB content of the fluid. The results of this analytical technique can be useful in selecting the appropriate handling and disposal procedure.
5.2 Quantification in this technique requires a peak-by-peak comparison of the chromatogram of an unknown specimen with that of standard Aroclor test specimens obtained under identical conditions. The amount of PCB producing each peak in the standard chromatogram shall be known independently.
5.3 The technique described is based on data for standard chromatograms of Aroclors 1242, 1254, and 1260 obtained using specific chromatographic column packing materials and operating conditions.4 Relevant chromatograms are reproduced in Fig. 1, Fig. 2, and Fig. 35, for isothermal packed columns and in Figs. X4.1 through X4.3) for temperature programmed mega-bore capillary columns. Each peak is identified by its retention time relative to that of a standard. The types and amounts of PCB associated with each peak have been determined by mass spectroscopy and are given in Table 1, Table 2, and Table 3.4 Other chromatographic operating conditions, and in particular, other column packing materials, may give different separations. The data given in the tables should not be used if chromatograms of the standards differ significantly from those shown in the figures. The peaks in such standard chromatograms shall be independently identified and quantified.
5.4 Different isomers of PCB with the same number of chlorine substituents can cause substantially different responses from EC detectors. Mixtures of PCB containing the same amount of PCB, but with a different ratio of isomers, can give quite different chromatograms. This technique is effective only when...
SCOPE
1.1 This test method describes a quantitative determination of the concentration of polychlorinated biphenyls (PCBs) in electrical insulating liquids by gas chromatography. It also applies to the determination of PCB present in mixtures known as askarels, used as electrical insulating liquids.
1.2 The PCB mixtures known as Aroclors2 were used in the formulation of the PCB-containing askarels manufactured in the United States. This test method may be applied to the determination of PCBs in insulating liquids contaminated by either individual Aroclors or mixtures of Aroclors. This technique may not be applicable to the determination of PCBs from other sources of contamination.
1.3 The precision and bias of this test method have been established only for PCB concentrations in electrical insulating mineral oils and silicones. The use of this test method has not been demonstrated for all insulating fluids. Some insulating liquids, such as halogenated hydrocarbons, interfere with the detection of PCBs and cannot be tested without pretreatment.
1.4 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
SIGNIFICANCE AND USE
5.1 Oil and oil-immersed electrical insulation materials may decompose under the influence of thermal and electrical stresses, and in doing so, generate gaseous decomposition products of varying composition which dissolve in the oil. The nature and amount of the individual component gases that may be recovered and analyzed may be indicative of the type and degree of the abnormality responsible for the gas generation. The rate of gas generation and changes in concentration of specific gases over time are also used to evaluate the condition of the electric apparatus.
Note 1: Guidelines for the interpretation of gas-in-oil data are given in IEEE C57.104.
SCOPE
1.1 This test method covers three procedures for extraction and measurement of gases dissolved in electrical insulating oil having a viscosity of 20 cSt (100 SUS) or less at 40°C (104°F), and the identification and determination of the individual component gases extracted. Other methods have been used to perform this analysis.
1.2 The individual component gases that may be identified and determined include:
Hydrogen—H2
Oxygen—O2
Nitrogen—N2
Carbon monoxide—CO
Carbon dioxide—CO2
Methane—CH4
Ethane—C2H6
Ethylene—C2H4
Acetylene—C2H2
Propane—C3H8
Propylene—C3H6
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 warning statements see 6.1.8, 30.2.2 and 30.3.1.
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.
- Standard22 pagesEnglish language
ABSTRACT
This specification covers a high fire point natural vegetable oil ester insulating fluid for use as a dielectric and cooling medium in new and existing power and distribution electrical apparatus such as transformers and attendant equipment. The physical property requirement including color, fire point, flash point, pour point, relative density, and viscosity shall be tested to meet the requirements prescribed. The electrical property requirements including dielectric breakdown voltage, dissipation factor, and gassing tendency shall be tested to meet the requirements prescribed. The chemical requirements including corrosive sulphur, neutralization number, PCB content, and water shall be tested to meet the requirements prescribed.
SCOPE
1.1 This specification covers a high fire point natural vegetable oil ester insulating fluid for use as a dielectric and cooling medium in new and existing power and distribution electrical apparatus such as transformers and attendant equipment.
1.2 Natural vegetable oil ester insulating fluid differs from conventional mineral oil and other high fire point (or “less-flammable”) fluids in that it is an agricultural product derived from vegetable oils rather than refined from petroleum base stocks or synthesized from organic precursors.
1.3 This specification is intended to define a natural vegetable oil ester electrical insulating fluid that is compatible with typical materials of construction of existing apparatus and will satisfactorily maintain its functional characteristic in this application. The material described in this specification may not be miscible with some synthetic electrical insulating liquids. The user should contact the manufacturer of the natural ester insulating fluid for guidance in this respect.
1.4 This specification applies only to new insulating fluid as received prior to any processing. The user should contact the manufacturer of the equipment or fluid if questions of recommended characteristics or maintenance procedures arise.
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.
- Technical specification4 pagesEnglish language
SIGNIFICANCE AND USE
2.1 A gas sample from above the insulating liquid in transformers and other electrical power apparatus can be used to give an early indication of developing fault conditions. Combustible gases are formed from the breakdown of the insulating materials under thermal and electrical stress. Excessive concentrations of combustible gases indicate the need to take appropriate action.
2.2 It is important that gas samples from equipment be taken from the gas space directly above the liquid level, and not from remote expansion compartments, such as tank bracing bands.
2.3 The procedure described should be carefully followed to ensure that the sample is not diluted by air or nitrogen, or contaminated by residual materials in the sampling bottle.
SCOPE
1.1 This practice covers the sampling of gas above the insulating liquid of a transformer. A gas sampling bottle collects the gas sample from the gas space that is at a positive pressure.
1.2 Representative samples of gas are taken for analysis to determine their compositions.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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.
- Standard2 pagesEnglish language
SIGNIFICANCE AND USE
4.1 The approximate acidity of used electrical insulating oils is an estimate of the total acid value of the oil. As acid values increase, oil quality decreases. This is usually due to oxidation of the oil while in service. In general, acidic by-products produce increased dielectric loss, increased corrosivity, and may cause thermal difficulties attributable to insoluble components called “sludge.” This test method is adapted to a specific volume of oil; total acid values of 0.05 to 0.5 mg of potassium hydroxide per gram of oil is a range which is functionally significant.
SCOPE
1.1 This test method describes the determination of the approximate total acid value of used electrical insulating liquids having viscosities less than 24 cSt at 40°C. It is a simple procedure that can be applied in the field. Where a quantitative neutralization value is required, use Test Method D664 or Test Method D974. These test methods should be applied in the laboratory.
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 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.
- Standard3 pagesEnglish language
ABSTRACT
This specification covers three types of nitrogen gas used as an electrical insulating material in electrical equipment: Type I, obtained from the air by liquefaction processes and dried; Type II, obtained from the air by liquefaction processes, deoxidized with hydrogen over a platinum catalyst, and dried; and Type III, obtained from the air by liquefaction processes and if necessary deoxidized by suitable means. Materials shall be tested and the individual grades shall conform to specified values of % volume of nitrogen and rare gases, hydrogen, and oxygen; and dew point.
SCOPE
1.1 This specification covers three types of nitrogen used as an electrical insulating material in electrical equipment:
1.1.1 Type I, obtained from the air by liquefaction processes and dried,
1.1.2 Type II, obtained from the air by liquefaction processes, deoxidized with hydrogen over a platinum catalyst, and dried, and
1.1.3 Type III, obtained from the air by liquefaction processes and if necessary deoxidized by suitable means.
Note 1: The fact that metal containers are filled with materials meeting this specification does not exclude the possibility that the materials might become contaminated with unlisted impurities.
1.2 The following safety hazards caveat pertains only to the test method portion, Section 5, of this specification: 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.
- Technical specification2 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Color is significant chiefly as an indicator of contamination in electrical insulating liquids. Frequently this contamination is the result of solvent action in the apparatus involved or it may indicate possible contamination. No definite relationship can be established between color and the physical and electrical characteristics of the liquid; for that reason color in itself has limited value as a measure of condition. For more precise determination of color, Test Method D1209 may be used.
SCOPE
1.1 This standard describes a test method for the visual determination of the color of clear insulating liquids.
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 limitations prior to use.
- Standard3 pagesEnglish language
- Standard3 pagesEnglish language
SIGNIFICANCE AND USE
4.1 Knowledge of the coefficient of thermal expansion of a liquid is essential to compute the required size of a container to accommodate a volume of liquid over the full temperature range to which it will be subjected. It is also used to compute the volume of void space that would exist in an inelastic device filled with the liquid after the liquid has cooled to a lower temperature.
SCOPE
1.1 This practice covers the determination of the coef-ficient of thermal expansion of electrical insulating liquids of petroleum origin, and askarels, containing PCBs (polychlorinated biphenyls), when used as an insulating or cooling medium, or both, in cables, transformers, oil circuit breakers, capacitors, or similar apparatus.
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 limitations prior to use.
- Standard2 pagesEnglish language
SIGNIFICANCE AND USE
4.1 For certain applications when insulating liquid is stressed at high voltage gradients, it is desirable to be able to determine the rate of gas evolution or gas absorption under specified test conditions. At present time correlation of such test results with equipment performance is limited.
4.2 In this test method, hydrogen (along with low molecular weight hydrocarbons) is generated by ionic bombardment of some insulating liquid molecules and absorbed by chemical reaction with other insulating liquid molecules. The value reported is the net effect of these two competing reactions. The aromatic molecules or unsaturated portions of molecules present in insulating liquids are largely responsible for the hydrogen-absorbing reactions. Both molecule type, as well as concentration, affects the gassing tendency result. Saturated molecules tend to be gas evolving. The relation between aromaticity and quantity of unsaturates of the insulating liquid and gassing tendency is an indirect one and cannot be used for a quantitative assessment of either in the insulating liquid.
4.3 This test method measures the tendency of insulating liquids to absorb or evolve gas under conditions of electrical stress and ionization based on the reaction with hydrogen, the predominant gas in the partial discharge. For the test conditions, the activating gas hydrogen, in contrast to other gases, for example, nitrogen, enhances the discrimination of differences in the absorption-evolution patterns exhibited by the insulating liquids. Insulating liquids shown to have gas-absorbing (H2) characteristics in the test have been used to advantage in reducing equipment failures, particularly cables and capacitors. However, the advantage of such insulating liquids in transformers is not well defined and there has been no quantitative relationship established between the gassing tendency as indicated by this test method and the operating performance of the equipment. This test method is not concerne...
SCOPE
1.1 This test method measures the rate at which gas is evolved or absorbed by insulating liquids when subjected to electrical stress of sufficient intensity to cause ionization in cells having specific geometries.
1.2 This test method is not concerned with bubbles arising from supersaturation of the insulating liquid.
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 whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific precautions see 5.1.4 and 8.4.
- Standard5 pagesEnglish language
Frequently Asked Questions
D27 is a Technical Committee within ASTM International. It is named "Electrical Insulating Liquids and Gases" and is responsible for: The promotion of knowledge pertaining to electrical insulating liquids and gases, whether of synthetic or natural origin, and the recommendation of standards pertinent to these materials. The principal materials included in this scope are oils of petroleum origin, synthetic liquids, halogenated and other gases, when used, singularly or as combinations, as electrical insulation or as an environment for electrical insulation. Standards peculiar to solid insulating materials and varnishes and the development of standards pertaining to the nonelectrical uses of liquid and gaseous materials are excluded from the scope of Committee D27. Development in these fields incidental to the normal work of Committee D27 will be coordinated with the appropriate technical committees of the Society. This committee has published 293 standards.
D27 develops ASTM standards in the area of Information technology. The scope of work includes: The promotion of knowledge pertaining to electrical insulating liquids and gases, whether of synthetic or natural origin, and the recommendation of standards pertinent to these materials. The principal materials included in this scope are oils of petroleum origin, synthetic liquids, halogenated and other gases, when used, singularly or as combinations, as electrical insulation or as an environment for electrical insulation. Standards peculiar to solid insulating materials and varnishes and the development of standards pertaining to the nonelectrical uses of liquid and gaseous materials are excluded from the scope of Committee D27. Development in these fields incidental to the normal work of Committee D27 will be coordinated with the appropriate technical committees of the Society. Currently, there are 293 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.