Abstract
Programmable logical controller (PLC) is by the automatic control technology, the computer technology and the communication the new generation of industry control device which develops for the foundation, its collection sequential control, the process control and the data processing with a body, have the function formidable, the reliability high, the use nimble convenient, easy to program, the maintenance simple, as well as are suitable for under the industry environment the application and so on a series of merits, in the industrial automation, the integration of machinery, aspects and so on traditional technology industry transformation obtained the widespread application, has become one of modern industry control props. This article loses the specify programmable logic controller in the thermal power plant in the coal process the application, because loses the coal system equipment to be many, the duty is arduous, the region is dispersible, the environment is bad, the noise and the dust pollution is serious, in order to reduce the movement personnel's labor intensity, reduces the adverse circumstance to the field work personnel body harm, enhances the working efficiency and the safe operation level, therefore we use the programmable logical controller to carry on the control to it, enables its to be possible to complete the start automatically, stops, the breakdown reports to the police, functions and so on breakdown engine off, thus plays saves the cost, protects the field work personnel's role.
Our this design completes the primary mission has：
(1) The selection of PLC hardware system ;
(2) The selection of PLC development software system ;
(3) Draws up the flow chart of the Transportation coal control system ;
(4) Programming the software of the PLC control system;
Key words：programmable logical controller，I/O lag, Scan-round, ladder diagram
