how to do oil filtration of transformer?

To perform oil filtration of a transformer, first, isolate the transformer from the power supply and drain the insulating oil. Use a vacuum oil filtration system or a portable oil filtration unit equipped with filters to remove moisture, particulate matter, and sludge from the oil. Ensure the oil is heated to reduce viscosity for better filtration. After filtration, test the oil for dielectric strength and other properties before refilling the transformer. Finally, monitor the transformer for any signs of leakage or issues.