Abstract: There are 6 powder ore bins in a concentrator, 1 discharge car, the discharge car can carry a positive and negative ore conveyor belt. In the actual production process, the discharge car is controlled manually, and it relies on the manual observation of the material level of the ore bin and the position of the trolley to move the trolley, which seriously affects the production efficiency, dust and noise pollution threaten the health of operators. In order to solve the above problems, an automatic control algorithm based on multi-source location is designed, and the key position signal recognition is realized by means of discrete signal and continuous location, and based on Siemens PLC Design and development of automatic discharge system, discharge car to achieve automatic control, improve the working environment of operators, improve the efficiency of discharge production.