How is dielectric strength and water content checked in transformer oil?

To check the dielectric strength of transformer oil, a device known as a dielectric strength tester, such as the Globecore D97 tester, is used. This tester applies a voltage to the oil sample until breakdown occurs, providing a measure of its dielectric strength, which is crucial for ensuring the oil’s insulating properties. Water content in transformer oil can be determined using Globecore’s moisture analyzers, which employ various techniques like Karl Fischer titration or capacitive sensing. These tests help ensure that the transformer oil maintains its performance and longevity by verifying that both dielectric strength and moisture levels are within acceptable limits.