ASTMD149美标标准固体绝缘材料电压击穿的实验方法Word版.doc

ASTMD149美标标准固体绝缘材料电压击穿的实验方法Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies 固体电绝缘材料在工业用电频率下的电压击穿和介电强度的实验方法1. Scope*1.1 This test method covers procedures for the determination of dielectric strength of solid insulating materials at commercial power frequencies, under specified conditions.2,31.2 Unless otherwise specified, the tests shall be made at 60Hz. However, this test method is suitable for use at anyfrequency from 25 to 800 Hz. At frequencies above 800 Hz,dielectric heating is a potential problem.1.3 This test method is intended to be used in conjunction with any ASTM standard or other document that refers to this test method. References to this document need to specify the particular options to be used (see 5.5).1.4 It is suitable for use at various temperatures, and in any suitable gaseous or liquid surrounding medium.1.5 This test method is not intended for measuring the dielectric strength of materials that are fluid under the conditions of test.1.6 This test method is not intended for use in determining intrinsic dielectric strength,direct-voltage dielectric strength,or thermal failure under electrical stress (see Test MethodD3151).1.7 This test method is most commonly used to determine the dielectric breakdown voltage through the thickness of a test specimen (puncture). It is also suitable for use to determine dielectric breakdown voltage along the interface between a solid specimen and a gaseous or liquid surrounding medium (flashover). With the addition of instructions modifying Section 12, this test method is also suitable for use for proof testing.推荐精选1.8 This test method is similar to IEC Publication 243-1. All procedures in this method are included in IEC 243-1. Differences between this method and IEC 243-1 are largely editorial.1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazardstatements are given in Section 7. Also see 6.4.1.ASTMD149美标标准固体绝缘材料电压击穿的实验方法(三)3.1 Definitions:3.1.1dielectric breakdown voltage (electric breakdown voltage), n—the potential difference at which dielectric failureoccurs under prescribed conditions in an electrical insulatingmaterial located between two electrodes. (See also Appendix X1.)3.1.1.1 Discussion—The term dielectric breakdown voltage is sometimes shortened to “breakdown voltage.”3.1.2dielectric failure (under test), n—an event that is evidenced by an increase in conductance in the dielectric under test limiting the electric field that can be sustained. 推荐精选3.1.3dielectric strength, n—the voltage gradient at which dielectric failure of the insulating material occurs under specific conditions of test. 3.1.4 electric strength, n—see dielectric strength.3.1.4.1 Discussion—Internationally, “electric strength” is used almost universally.3.1.5flashover, n—a disruptive electrical discharge at the surface of electrical insulation or in the surrounding medium, which may or may not cause permanent damage to the insulation.3.1.6 For definitions of other terms relating to solid insulating materials, refer to Terminology D1711.ASTMD149美标标准固体绝缘材料电压击穿的实验方法(四) 4. Summary of Test Method4.2 Most commonly, the test voltage is applied using simple test electrodes on opposite faces of specimens. The options for the specimens are that they be molded or cast, or cut from flat sheet or plate. Other electrode and specimen configurations are also suitable for use to accommodate the geometry of the sample material, or to simulate a specific application for which the material is being evaluated.4.1 Alternating voltage at a commercial power frequency (60 Hz, unless otherwise specified) is applied to a test specimen. The voltage is increased from zero or from a level well below the breakdown voltage, in one of three prescribed methods of voltage application, until dielectric failure of the test specimen occurs.5. Significance and Use推荐精选  5.1 The dielectric strength of an electrical insulating material is a property of interest for any application where an electrical field will be present. In many cases the dielectric strength of a material will be the determining factor in the design of the apparatus in which it is to be used.5.2 Tests made as specified herein are suitable for use to provide part of the information needed for determining suitability of a material for a given application; and also, for detecting changes or deviations from normal characteristics resulting from processing variables, aging conditions, or other manufacturing or environmental situations. This test method is useful for process control, acceptance or research testing.5.3 Results obtained by 。