Abstract
In order to communicate with a PLC (Programmable Logic Controller) flexibly and freely, a data communication model based on the PLC's free port is designed. In the structure of the model, a distributed data communication environment is constructed by using Ethernet and serial adapters. In the communication algorithm, a method of queue-buffer for multi-threaded is used to improve the real-time of the control. This communication model has good scalability and portability because the realization of it is not restricted by the number of PLC slave stations and the type of operating system of the host computer. A corresponding communication algorithm is applied to data collection and devices monitoring for a pipe pneumatic conveying system. The practice shows that not only the stability and reliability of the model can meet the needs of automatic control but also the communication performance and efficiency of the model is outstanding.
Highlights
PLC as the industrial automatic control equipment encompassing the automation technology, computer technology, control technology and communications technology, has been widely used in various fields of industrial automation [1]
Taking Siemens S7-200 series as an example, a control system consisting of this series PLC can generally use configuration software monitoring, third-party monitoring-software monitoring, touch screen monitoring and other monitoring methods [2]
Freeport communication is a method of using serial communication hardware and relevant instructions for customizing communication protocols which are provided by the PLC to realize data communication by PLC programming
Summary
PLC as the industrial automatic control equipment encompassing the automation technology, computer technology, control technology and communications technology, has been widely used in various fields of industrial automation [1]. The literatures [3] and [4] have described the implementations of the Siemens PLC communication method on free port. Technology, namely realizing the data acquisition and control of PLC through the serial communication of host computer. This paper describes an approach which is based on Ethernet and serial adapters to achieve distributed data communication model through the PLC free port. This model has the advantage of being crossplatform and can be implemented in different operating systems. In order to achieve the acquisition of data and the control of PLC efficiently and stably, the communication algorithm based on queue-buffer for multithreaded is designed. Structure of the system and related communication model and algorithm are discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Advanced Computer Science and Applications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
