Dielectric loss measurements — General techniques & significance

The dielectric losses — dissipation factor, dielectric constant and loss index — are important parameters for selection and control of dielectrics for diverse electrical insulating applications. These properties are indices of the effectiveness of a material as an electrical insulation in a wide variety of applications, are guides for control of quality and lot variations, and are significant guideposts for evaluation of the effectiveness of research effort. However, actual values often are influenced strongly by the environment, the electrical frequency and potential level, the history of the material, and the intimacy of the conductor to the dielectric. Therefore, the test environment and apparatus must be rigidly controlled to obtain significant or precise results.