The basic principle of PLC automatic control system design
PLC automatic control system (automatic control systems) is a control system that enables the production process or other processes to be carried out according to the desired law or predetermined program without direct participation of no one. Automatic control system is the main means to realize automation, referred to as automatic control system.
According to different control principles, PLC automation control systems can be divided into open-loop control systems and closed-loop control systems; according to the classification of given signals, automatic control systems can be divided into constant value control systems, follow-up control systems and program control systems. And any control system is to achieve the process requirements of the controlled object to improve production efficiency and product quality. Therefore, when designing the PLC automation control system, Nanning Dachao Electric summarized the following basic principles:
Satisfying the control requirements of the controlled object to the
greatest extent It is the primary prerequisite for the design of the PLC automation control system to give full play to the functions of the PLC and to meet the control requirements of the controlled object to the greatest extent . This is also the most important principle in the design. This requires designers to conduct in-depth investigations and research on site before designing, collect and control site data, and collect relevant advanced domestic and foreign data. At the same time, attention should be paid to working closely with on-site engineering management personnel, engineering technicians, and on-site operators to formulate control plans and jointly solve key and difficult problems in the design.
Ensuring the safety and reliability of the
PLC automation control system Ensuring that the PLC automation control system can operate safely, reliably and stably for a long time is an important principle for the design of the control system. This requires the designer to fully consider the system design, component selection, and software programming to ensure the safety and reliability of the control system. For example: It should be ensured that the PLC program not only runs under normal conditions, but also works normally under abnormal conditions (such as sudden power failure and then power-on, wrong button press, etc.).
Strive for simplicity, economy, ease of use and maintenance.
A new control project can certainly improve the quality and quantity of products and bring huge economic and social benefits, but the investment in the new project, technical training, and equipment maintenance will also lead to operation Increase in funding. Therefore, under the premise of meeting the control requirements, on the one hand, we must pay attention to continuously expanding the benefits of the project, and on the other hand, we must also pay attention to continuously reducing the cost of the project. This requires designers not only to make the control system simple and economical, but also to make the use and maintenance of the control system convenient and low-cost, and it is not advisable to blindly pursue automation and high indicators.
Adapting to the needs of development
Due to the continuous development of technology, the requirements of the control system will continue to increase. The design should take into account the needs of future control system development and improvement. This requires a proper margin when selecting PLC, input/output modules, I/O points and memory capacity to meet future production development and process improvement.
This article comes from: https://www.zhinengdianli.com/zidonghua/PLC/