The dielectric strength of transformer oil is a measure of its ability to resist electrical breakdown under an applied voltage. It is a critical parameter for the insulation properties of the transformer, as transformer oil is used as an insulating material to prevent electrical breakdown and short circuits.
The dielectric strength of transformer oil is typically measured in kilovolts per millimeter (kV/mm) or in kilovolts per inch (kV/in). The minimum dielectric strength required for transformer oil can depend on various factors, including the voltage rating of the transformer, the size and design of the transformer, and the applicable industry standards.
In general, the dielectric strength of transformer oil should be high enough to withstand the expected electrical stress without breakdown. The standard minimum dielectric strength for transformer oil is typically around 30 kV/mm or 750 kV/in, but in practice, values of 50 kV/mm or higher may be preferred for high-voltage transformers or those subjected to high electrical stress. Transformer oil with higher dielectric strength will provide better insulation properties and greater safety margin against electrical breakdown.