The control box adopts advanced technologies such as separate excitation circuit under microcomputer control, automatic frequency tracking and frequency sweeping mode. Compared with the traditional control box, it has stable and reliable operation, continuously adjustable ultrasonic power, and can maximize the potential of the transducer. Automatic tracking of working frequency makes output matching better, power more powerful and efficiency higher. The unique frequency sweeping working mode makes the cleaning solution form a small reflux under the effect of frequency sweeping, and timely carries the dirt stripped off by ultrasonic wave away from the workpiece surface, so as to achieve a faster and more thorough cleaning effect and higher ultrasonic cleaning efficiency. At the same time, it has perfect protection functions: overheat protection and overcurrent protection, which makes the work more reliable.