Abstract: The present invention relates to an electromotor where its operational values, such as speed and torque, can be changed by means of a static frequency converter. The invention relates further to an electromotor combined with and driving a working unit such as a pump, a ventilator a machine tool or a tool. The frequency converter miniaturized by means of a high-integrated circuit is mechanically connected to form a structural unit with the motor or the working unit, and the dissipation heat of the frequency converter is emitted, preferably by means of ducted cooling, and the metal parts surrounding the frequency converter form the electric shielding thereof.