How is the breakdown voltage test of transformer oil conducted?

The breakdown voltage test of transformer oil is conducted using a standardized method, typically following ASTM D1816 or IEC 60156 protocols. A sample of the oil is placed between two electrodes in a test cell. The voltage is gradually increased until the oil fails, causing a dielectric breakdown. The breakdown voltage is recorded as the voltage at which the spark occurs. This test assesses the insulating properties of the oil, ensuring it meets operational standards for transformer performance.