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

The procedure for transformer oil filtration in power transformers involves several key steps. First, the transformer is isolated and the oil is drained into a filtration unit. The oil is then heated to reduce viscosity, allowing for better flow. Filtration systems, often equipped with vacuum and fine filtration processes, remove moisture, particulate matter, and dissolved gases. Finally, the filtered oil is tested for quality before being returned to the transformer, ensuring optimal performance and longevity.