An overview of dielectric measurements

It is noted that, approximately 25 years ago, commercial electronic instruments were brought on the market that heralded a new era in dielectric measurements; this electronic era is now rapidly drawing to a close, and is on the verge of being eclipsed by an era that could be called intelligent instruments. The development of dielectric measurement technology before and after the founding of the Dielectrics and Electrical Insulation Society is discussed, with the main emphasis on measurement of permittivity and related matters in the lower range of frequencies. Attention is given to the interpretation of results and the instrumental errors may occur