What is the purpose of a BDV test in transformers?

A BDV (Breakdown Voltage) test in transformers is essential for assessing the insulating properties of transformer oil, which plays a critical role in ensuring the safe and efficient operation of the transformer. The primary purpose of the BDV test is to determine the voltage level at which the insulating oil breaks down, leading to electrical discharge and potential failure of the transformer. A high BDV value indicates that the oil is still capable of providing effective insulation, while a low value may suggest contamination, moisture presence, or degradation, necessitating maintenance or oil replacement to prevent operational faults. Regular BDV testing is thus vital to maintain transformer reliability and extend its service life, aligning with best practices in transformer management.