subject: Function and usability of the system PLC [print this page] Function and usability of the system PLC Function and usability of the system PLC
PLC is a system that can manipulate, execute, and / or monitor the state of the process at a very rapid rate, with the basic data that can be programmed into the integral microprocessor-based systems. PLC receives input and generates output electrical signals to control a system. Thus, quantities of chemical physics and controlled, before processed by the PLC, will be converted into electrical signals either analog or digital, which is basically data. Characters controlled by the PLC process itself is a gradual process that in nature, i.e. the process running order to achieve the expected end state. In other words, the process comprises several sub processes, in which a particular sub process will run after the previous sub process occurs. A general term used for the process that character is thus a sequential process (sequential process). For comparison, the control system of a popular addition to the PLC, such as Distributed Control System (DCS), able to handle the processes that are sequential and continuous (continuous process) and also includes a relatively large loop control.
The function and usefulness of the PLC can be said is almost unlimited. But in practice can be divided in general and specific.
In general, the function of PLC are as follows:
1. Control Sequential
PLC processing binary input signals into outputs that are used for the purposes of processing techniques sequentially (sequential), here the PLC to maintain that all the step / steps in a sequential process takes place in the proper sequence.
2. Plant Monitoring
PLC continuously monitors a system (e.g. temperature, pressure, level of altitude) and take necessary action in connection with a controlled process (for example, already exceeds the limit value) or displays a message to the operators.
