Patent ID: 7675219

Claim:
A method for controlling an ultrasonic unit of an ultrasonic cleaning system comprising at least one control unit, one generator unit and one hand-held unit containing the ultrasonic unit and one switching module provided for starting the ultrasonic unit, wherein mechanical oscillations can be generated via the ultrasonic unit and transmitted to an instrument that is mechanically connected to the ultrasonic unit, wherein after actuating the switching module by a control routine executed in the control unit, a resonant frequency required for operation of the ultrasonic unit in resonance is determined and a control signal (ss) based on the determined resonant frequency is generated in the generator unit and is sent to the ultrasonic unit for operation of the ultrasonic unit in resonance wherein a coarse tuned resonant frequency of the ultrasonic unit is determined by means of a coarse tuning routine executed in the control unit.