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. Designation: D150 - 18 INTERNATIONAL Standard Test Methods for AC Loss Characteristics and Permittivity (Dielectric Constant) of Solid Electrical Insulation This standard is issued under the fixed designation D150; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. Anumber in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the U.S. Department of Defense. 1. Scope 2. Referenced Documents 1.1 These test methods cover the determination of relative 2.1 ASTM Standards:4 permittivity, dissipation factor, loss index, power factor, phase D374 Test Methods for Thickness of Solid Electrical Insu- angle, and loss angle of specimens of solid electrical insulating lation (Metric) D0374_D0374M D618 Practice for Conditioning Plastics for Testing materialswhenthestandardsusedarelumpedimpedances.The frequency range addressed extends from less than 1 Hz to D1531Test Methods for Relative Permittivity (Dielectric Constant) and Dissipation Factor by Fluid Displacement several hundred megahertz. Procedures (Withdrawn 2012)5 Nore 1In common usage, the word relative is frequently dropped. D1711 Terminology Relating to Electrical Insulation D5032 Practice for Maintaining Constant Relative Humidity 1.2 These test methods provide general information on a by Means of Aqueous Glycerin Solutions variety of electrodes, apparatus, and measurement techniques. E104 Practice for Maintaining Constant Relative Humidity A reader interested in issues associated with a specific material by Means of Aqueous Solutions needs to consult ASTM standards or other documents directly applicable to the material to be tested.2,3 3. Terminology 1.3 This standard does not purport to address all of the 3.1 Definitions: safety concerns, if any, associated with its use. It is the 3.1.1UseTerminologyD1711fordefinitions of termsused responsibility of the user of this standard to establish appro- in these test methods and associated with electrical insulation priate safety, health, and environmental practices and deter- materials. minethe applicability of regulatory limitationsprior to use. 3.2 Definitions of Terms Specific to This Standard: For specific hazard statements, see 10.2.1. 3.2.1 capacitance, C, nthat property of a system of conductors and dielectrics which permits the storage of elec- 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- trically separated chargeswhenpotential differencesexist between the conductors. ization established in the Decision on Principles for the 3.2.1.1 Discussion-Capacitance is the ratio of a quantity, q, DevelopmentofInternationalStandards,GuidesandRecom- of electricity to a potential difference, V. A capacitance value is mendations issued by the World Trade Organization Technical always positive. The units are farads when the charge is Barriers to Trade (TBT) Committee. expressed in coulombs and the potential in volts: C = q/V (1) 3.2.2 dissipation factor, (D), (loss tangent), (tan S), n-the I These test methods are under the jurisdiction of ASTM Committee D09 on ratio of the loss index (k") to the relative permittivity (k') which Electrical and Electronic Insulating Materials and are the direct responsibility of Subcommittee D09.12 on Electrical Tests. is equal to the tangent of its loss angle (8) or the cotangent of Current edition approved May 1, 2018. Published May 2018. Originally its phase angle (0) (see Fig. 1 and Fi