A study of residual charge of condenser

Abstract

For many years it has been known that the complete charging and discharging of a condenser with complex dielectric involved a time element. Particularly, it was noted that a condenser could be discharged to zero potential, allowed to stand for an interval of time and a discharge then secured from the condenser. In some cases even after months a discharge could be obtained. The accumulation of such a charge on a condenser is spoken of no residual charge or dielectric absorption.

The Lyden jar was used extensively in the early work on residual charge. Physicists such as Benjamin Franklin, Faraday, and Maxwell recognized this. In fact Maxwell gives us the first attempt ever made at a theoretical explanation of the phenomena of absorption.¹ Today this is the principal theory recognized in the Physics world for this phenomena.

It was not until the day of speech communication over long distances that a study of the dielectric was given considerable attention. Theories have been developed for the explanation of dielectric absorption, some of which will be mentioned later. Even today large inconsistencies are found to exist between theory and experiment in this field of work.

There are numerous factors upon which dielectric absorption depends. Some of these are, material or dielectric, previous history, charging potential, moisture content, air content, charge time, discharge time, recovery time, and temperature.

It is the purpose of this paper to present results of experiment and to state conclusions drawn from work on temperature effects on residual charge of a paraffin paper dielectric. Through the study which has been made of this phenomenon it is felt information has been gained which can be added to our now small understanding of absorption.