What is the procedure for filling transformer oil in power transformers?

The procedure for filling transformer oil in power transformers involves several key steps. First, ensure the transformer is de-energized and properly grounded. Next, connect the oil filling equipment to the transformer’s filling port. Carefully monitor the oil level during the filling process to prevent overfilling. After reaching the desired level, check for any air bubbles and perform a vacuum treatment if necessary. Finally, seal the filling port securely to maintain the integrity of the transformer oil.