Automatic Constant Feed Speed Control: Automatic output voltage adjustment in real-time to ensure constant preset feed speed regardless of weight change of the workpieces. Automatic Resonant Frequency Search: Search out and output the resonant frequency of the load. other related parameters are also set automatically Rs485 Communication: All parameters of the controller can be adjusted via R485. Sync Output: Sync the output waveform of the slave controller with that of the master controller to the same frequency and phase to avoid beat effect Digital Overheat Protection: If the internal temperature of the controller gets too high, the controller will stop its output to protect itself. Overcurrent Protection: If output current exceeds its rated value the controller will stop its output to protect itself and the load. Restorable Short Circuit Protection: If the controller's output is short-circuited, it will shut down its production to protect itself and the load. But the fuse inside will not be blown. So when there is no short circuit at the output side, the controller will work again after power is on.