1st gear speed is 2500, and each subsequent gear increases by 500
U211B3 constant speed and constant power functions are mainly achieved by comparing the set speed with the actual speed signal through the internal operational amplifier and adjusting the conduction angle of the AC current.
The speed feedback of U211B3 is induced by an inductor and the magnet on the motor to form a sine wave speed signal. This signal is converted into a voltage signal proportional to the speed through the f/V converter inside the 211B3 and sent to the reverse input of the operational amplifier. terminal, the forward input terminal of the op amp provides a fixed voltage through an external voltage divider circuit (this voltage determines the speed). The voltage at the forward input terminal and the voltage at the reverse input terminal are constantly compared, and the instantaneous values of the two are compared. , forming a difference voltage. The phase control unit inside the 211B3 automatically adjusts the conduction angle of the alternating current according to this voltage, thereby achieving constant power and constant speed.
The main symptom is that if the machine is pressed down hard during operation, the machine speed will not be reduced much.