Thisseriesfittorecoveryofinferiortransformeroil.1.Itutilizephysiochemicalmeanstorecoverdeterioratedtransformeroilandcircuitbreakeroilwhileremovingtheacidcontent,suspendedmatterandprecipitatedresiduesinoil.2.Itallowsforoperationwhiletransformerstaysrunninginnormalmannerwithoutswitchingoffpowerandchangeofoil.3.Thebasiccontentandanti-oxygenicpropertyofoilremainthesameaftertreatment,andisbroughtbacktothespecificationofnewoil;insulatorpropertyandsafetyofequipmentareenhancedwhilecostisreducedby90%comparedwithconventionalwayofoil-change.4.No.6-10darkcoloredoilcanberetrofittedtothecolorofNo.2-4oil.5.Themediumweardownfactorscanbereduced,whichenablesoilgettingbacktothespecificationofnewoil.)