Dielectric strength is an indicator used to assess insulation properties of transformer oil. It is very often equated with breakdown voltage, It is a measure of the ability of oil to withstand electric stress and has primary importance for safe operation of electrical Equipment.
Breakdown voltage is a minimum voltage applied to an insulation, resulting in its breaking down and becoming electrically conductive.
The Dielectric Strength of transformer oil is very important since it is essential in maintaining the reliable operation of power transformers
The Dielectric strength of transformer oil is also known as the breakdown voltage of the transformer oil. “Breakdown Voltage” (BDV) is measured by observing the voltage that is required to jump a spark between two electrodes immersed in the oil separated by a specific gap or distance. Also known as the sparking strength, the higher the voltage required to jump the spark, the higher the BDV will be in the oil. The lower the voltage required to jump the spark, the BDV will be lower indicating the presence of moisture content and other conducting substances in the oil
