An electrical appliance with a resonant motor for driving a vibratory component is provided that has a control unit for driving the resonant motor with a predetermined driving frequency and for measuring the motion-induced voltage of the resonant motor and for determining whether the measured voltage value coincides with a predetermined target voltage value or whether the measured voltage value has crossed over the predetermined target value. The control unit measures the motion-induced voltage at a predetermined time of measurement (tm) within a driving cycle.
