Dielectric Strength and Breakdown Voltage - ASTM D149 - Test Method

The purpose of this method is to set a standard testing method for finding the breakdown voltage and dielectric strength of solid electrical insulating materials with attention to their application in commercial power frequencies.


This method is used to determine the dielectric breakdown and dielectric strength of solid insulating materials using the Short-Time Test (Method A) or the Step-by-Step Test (Method B) in air or in oil.

Applications and Benefits

Lucideon provides quantitative results for the dielectric breakdown voltage and dielectric strength of electrically insulating materials in compliance with ISO 17025, 10 CFR 50 Appendix B and 10 CFR Part 21 quality management system requirements to support ASTM D149 testing requirements for industry.

Form of Results

Dielectric breakdown is generally reported in kilovolts (kV), while dielectric strength is reported in volts per mil (V/Mil). Certificates of Conformance are generated upon request.

Related Tests

  • Dielectric Constant and Dissipation Factor – ASTM D150
  • Surface Resistivity and Volume Resistivity – ASTM D257
  • Dielectric Breakdown Voltage of Insulating Liquids – ASTM D877
  • Dielectric strength, constant, and dissipation factors for rubber tape – ASTM D4325, D4388.

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