What is the procedure for testing the breakdown voltage of transformer oil?

The procedure for testing the breakdown voltage of transformer oil involves using a standardized test setup, typically following ASTM D1816 or IEC 60156 standards. A sample of transformer oil is placed in a test cell with two electrodes. An alternating voltage is gradually applied until the oil breaks down, creating a conductive path. The voltage at which this occurs is recorded as the breakdown voltage, indicating the oil’s insulating properties.