... , UL, RoHS, Reach, SGS PEW coated enameled copper wire for transformer winding material TI 155 polyester enameled copper round wire TI 180 ... oil-immersed transformer) CertificationsProcess of producing Technical test itermsMaximum Overall Diameter, Conductor Diameter, Film Thickness, Conductor Resistance, Elongation, Spring Back, Mandrel Winding, Sudden ...