ENERVAC developed the On-Line tap changer oil purifier filter (TFS-2) to reduce the carbon, water and metallic particles in tap changers. These contaminants are produced by arcing contacts during the transfer of loads from tap-to-tap in the tap changer compartment. By using this system, operation and maintenance costs are reduced and the system’s reliability is improved. Load tap changer problems can be effectively reduced with the use of ENERVAC’s on-line oil filtration system.