HWA143-TDM-PMC-V20 Ethernet Communication Card

Description

Whether the DCS configured by the user can be successfully applied, improve the control quality, reduce the impact caused by its faults, and facilitate monitoring and operation, the key is the quality of configuration design. DCS user configuration refers to the design, implementation, and determination of relevant arrangements in DCS based on the characteristics, quantity, and performance of the functional components provided by the manufacturer, and according to the process design requirements. DCS user configuration work is a very meticulous task. During the configuration process, it is necessary to understand the control requirements of the production process, be familiar with the production process, have a deep understanding of the production sequence of various equipment and processes, and clarify the interrelationships between the production process and instruments; It is also necessary to proficiently master the various control algorithms or module functions provided by DCS, as well as the mutual influence of various parameters provided by each functional module, to have a clear understanding of DCS, process production processes, and control requirements in depth and breadth, and to complete configuration work.

Hardware arrangement configuration
DCS hardware arrangement refers to the distribution between the wiring positions on the DCS input/output equipment and the external production process parameter positions. One of the design ideas of DCS is decentralized control, and a reasonable combination of input/output signals can disperse the load.

Hardware should be configured in a balanced manner: empty slots and reserved I/O connections should be arranged in a decentralized manner, while minimizing the relative balance of loads between control stations. Avoiding centralized configuration can easily cause local information to flow through congestion and create bottlenecks, thereby reducing the overall performance of DCS, hindering the reasonable adjustment of I/O signals, and increasing the difficulty of system transformation in the future. At the same time, each card will set different execution cycles for signals based on actual changes and importance, and the signals of different execution cycles will be reasonably combined according to their physical positions. For example, LIC101, LIC102, LIC203, LIC206, LIC403 are important control points in the production process. The execution cycle is set to 50ms, while the relative parameters such as LI201, LI202, LI204, and LI205 change slowly. Therefore, the execution cycle is set to 100ms, which matches the execution cycle speed of the same card together, making the load of the input/output component microprocessing unit more uniform and reducing hardware failures due to excessive load. At the same time, parameters related to process operations, such as the liquid level of the hydrogenation liquid storage tank LIC102, the pump outlet flow rate FIC104, the oxidation liquid storage tank liquid level LIC206, the pump outlet flow rate FIC204, the regeneration liquid storage tank liquid level LIC403, and the flow rate FIC401. During the production process of this device, the hydrogenation liquid, oxidation liquid, and regeneration liquid are circulated. In order to maintain stable liquid level, flow balance is necessary. These interrelated parameters are allocated to different cards. When a certain card fails, it can be judged from relevant parameters to avoid widespread control paralysis and minimize risks.

Application software configuration
The application software configuration is completed at the engineer station and downloaded to the DCS controller for execution. The controller mainly consists of CPU, ROM, RAM, E2PROM, address setting switch, etc. The CPU performs calculations, while the ROM is used to store the operating system and function block library. The arrangement of function blocks in the ROM is determined and cannot be changed by the user. RAM is used to store the CPU’s calculation results and I/O signals. The control scheme of E2PROM memory function block connection. When powered down, the control scheme will not be lost. Moreover, the control scheme is not suitable and can be modified. The controller should have an address in the network, set by these address switches. The arrangement of functional blocks in ROM has corresponding addresses. When using these function blocks, the relationship between the input and output operations of the function block should be indicated, as well as the many parameters required for the operation. When determining the control strategy to form a control plan based on the controlled object, select the functional blocks required for control in the functional block library, clarify the connection relationship between each functional block, and first define its address in E2PROM. The connection with other functional blocks is also represented by addresses, and fill in the required parameters to draw the functional blocks required for each control circuit and their connection relationships, These tasks are called configuration.

The most important function block in the function block library is the PID function block, whose output Y (t) and input X (t) have a proportional integral differential relationship, which plays an extremely important role in process control. When completing closed-loop control, it is necessary to use the PID function block.