1. Introduction to PLC
PLC (Programmable Logic Controller) is an electronic system that integrates automatic control technology, communication technology and computer technology.
Since its development, it has demonstrated very powerful performance and plays an increasingly important role in the press brake automation process. Because PLC uses storage logic to control logic through program storage, it has strong overall expandability and reliable stability.
Therefore, in practical applications, your program can be easily modified to suit real work.
This article mainly discusses the application of PLC control technology in press brake automation, as well as PLC control anti-interference technology in press brake automation. It proposes some points and personal experiences on the application of PLC control technology in press brake automation.
In order to ensure that the PLC control system has strong automatic fault diagnosis and anti-interference performance, operators will choose to use isolation, grounding and filtering during the design process, and the operation of these means makes the application of PLC each increasingly extensive.
Furthermore, because the PLC uses a logical control mode, it can control a single device or an entire production line. In addition, it also has the ability to communicate with various types of PC machines, which is of great importance for the development of press brakes.
Therefore, PLC has been widely used in the field of electrical control of press brakes. In addition, smarter and more advanced control technologies have emerged.
2. Analysis of PLC control application in press brake
Since the advent of the information age, flexibility, intelligence, networking and digitalization have injected vitality into PLC. This provided greater development space and opportunities for automation in press brakes.
The variety of products on the market will become more abundant, specifications will be more complete, and technical development or automation design personnel will be able to better solve practical problems by developing perfect human-machine interfaces and comprehensive communication equipment.
They can also be flexibly developed to meet various control requirements, such as:
2.1 Electrical switch control on press the brake
In practice, PLC switch automatic control, as a substitute for relay control, can greatly increase the reliability and stability of the control system.
At the same time, PLC technology can design the ladder diagram according to the formula and program set by the sequential controller, which is a great highlight. The main advantages of this part are:
(1) PLC technology fast response speed in problem processing, easy operation, maintenance and maintenance, high control stability and reliability;
(2) The application of PLC switches can improve system quality, save operation time, and solve the difficulty of system route modification. From the current application of PLC control systems, it has been widely used in many fields.
With the continuous development of this technology, its application space is becoming wider and its role in switch control is being explored and developed.
2.2 Analog control and centralized control of the press brake system
Typically, due to the logic instructions such as (AND) or (OR), not (NOT) defined by the PLC, these logic instructions compensate for the shortcomings of traditional relay control methods and can complete the logic control.
They can also effectively apply it to single-machine control, cluster control, and multi-equipment coordination production line control. The use of PLC control systems in these scenarios shows their inherent performance advantages, which effectively improve production efficiency.
2.3 Analog control in press brake
Based on a clear understanding of the basic characteristics of the controlled object, the PLC can achieve automatic control.
Generally speaking, PLC control system mainly involves three types of modules: host module, position control module and high-speed calculation module.
The analog quantity of these modules can effectively improve the control accuracy of the system.
At the same time, the application of PLC control system can better control the heat treatment process such as insulation and cooling.
This feature is incomparable to other control systems and therefore has been preferred by many technicians.
2.4 Position control in the press brake
When PLC is applied to actual production processes, it can make the machine tool column complete compensation control and effectively achieve accurate spindle separation.
The application of PLC control system in the intelligent equipment manufacturing and automation industry greatly increases the degree of automation and intelligence of the production system, effectively realizing precise control of the system and greatly improving the accuracy of production.
In its actual application, repeated and subtle adjustments are required, which fully reflects the fast response characteristics of the PLC system.
3. Resistance to PLC interference in press brake automation control
There are many electronic circuits and instruments in the field of press brake automation, and it is difficult to avoid interference. The sources of interference for PLC mainly include: system external interference, various radiation interference, PLC system internal interference (electromagnetic radiation between internal circuits or components) and system external interference.
To solve the problems caused by interference and increase the anti-interference ability of the PLC, the following technical means can be adopted:
(1) Select equipment with strong anti-interference ability.
Performance parameters such as electromagnetic compatibility and resistance to external interference must be mastered, as well as the withstand voltage range and permitted electric field strength.
If it is necessary to purchase imported products, the difference between domestic and foreign voltages must be fully considered, and the selection and acquisition must be carried out strictly in accordance with national standards.
(2) Comprehensive anti-interference design
The. Effectively install power cables, take insulation and filtering measures when laying external cables, and effectively reduce electromagnetic interference caused by laying external cables;
B. Implement protection measures against electromagnetic interference radiation in the system;
w. Carefully and reasonably select the grounding point, and then use relevant software to improve the safety and stability of PLC control.
In addition, in practical applications, other methods can also be used to improve the system's anti-interference performance, such as:
First, improve the performance of the power supply itself to reduce interference caused by the power grid;
Secondly, reasonably plan the grounding points and perfect the grounding system;
Third, implement layered cable installation based on their functions to reduce signal interference between cables.
Comprehensive use of these measures can improve the anti-interference performance of the system to a certain extent and ensure its stable installation and operation.
4. Precautions for applying PLC control technology to press brakes
When applying PLC control technology to press brakes, attention should be paid to key parameters such as temperature (°C), humidity (ρw), vibration (m/s*s), etc., mainly including:
First, temperature control.
The working temperature limit of PLC control is 0-55°C, so the heat dissipation problem must be considered. It should be away from equipment with high heat generation.
If the temperature around the PLC exceeds 55°C, cooling measures must be taken, such as installing relevant refrigeration or ventilation devices to cool it to a temperature at which the PLC can operate normally.
Second, humidity control.
To further ensure the stability of PLC components and the quality of operation, a suitable working environment must be created, paying special attention to temperature and humidity control.
Since the insulation performance of PLC components may be affected by the environmental water vapor content, the environmental humidity should be controlled below 80%.
Third, vibration control.
Try to avoid vibrations between 10-55 Hz in the PLC working environment. If vibration occurs within this range, specific measures must be taken to reduce vibration damage to PLC components.
5. Conclusion
In summary, PLC programmable controller is a fusion of multiple technologies, which has the advantages of good stability, high reliability, flexible application and convenient use.
Currently, it has been successfully applied to real production in workshops and factories.
At present, in processing automatic control problems in modern press brakes, PLC has become one of the most effective tools for solving practical problems.
With the development of scientific and technological personnel and related research and development, the functions of PLC in automatic control are becoming stronger and stronger.
In the future, we must continue to strengthen the development of PLC systems, fully play its role, and promote the healthy, rapid and smooth development of modern press brakes.
