Abstract: In particular to connect wires insulated with highly heat-resistant lacquer to terminal elements, the winding wire has hitherto been wrapped around a terminal element and connected mechanically and electrically at at least one connection point by the local application of energy with the removal of the insulation. During winding around the terminal element, the winding end is held under pretension and simultaneously vibrations, in particular in the ultrasonic region, are coupled into the winding wire/terminal element system at the connection point to apply energy. Preferably, the vibrations are coupled into the wire outside the connection point. As a result of the fact that the vibrations propagate via the tensioned wire and bring about a relative movement between winding material and terminal element, an insulating layer can be broken up at least partially and the electrical connection to the terminal element is made by ultrasonic welding.