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Application of the Industrial Control Configuration Software FIX32 in Water Treatment Plants Author: Huizhou Jiangbei Water Supply Corporation, Wen Jinyu Abstract: This paper provides an overview of the basic architecture of FIX32, and explains the development, application, and design approaches of this configuration software in water treatment plants. Keywords: FIX32 ； PLC ； Process Database 1 Overview: Water plant automation has emerged over the past decade as a result of the development of high technology. With the advancement of automatic control technologies, system control equipment, electromechanical instrumentation, and the increasing prevalence of computers, water plant automation has also seen rapid development. At present, the automation in our factory is most prominently reflected in the water purification process. This includes field equipment (such as chlorination machines, alum injection pumps, valves, water pumps, etc.), process instruments (flow meters, SCD devices, turbidity meters, pH meters, etc.), PLCs, and industrial control configuration software. The PLC modules used in our factory are from Mitsubishi’s A1S series in Japan, while the industrial control software is version FIX32 V6.15 by Intellution. 2 Usage of FIX32: We have placed two computers in the central control room of the water treatment plant; both operate under the WINDOWS NT operating system, and each is equipped with a set of industrial automation configuration software version FIX32 V6.15. The purpose of these two computers is to provide one as a primary unit and the other as a backup. They are all connected to the lower-level PLC. One of the computers is also responsible for transmitting production data to the head office control room. As shown in Figure 1: Figure 1 shows the usage of FIX32. The basic functions of the industrial control configuration software FIX32 include data acquisition and data retrieval ； Data management refers to the ability to control and process the collected data, which includes graphic display, data monitoring, alarm functions, reporting functions, and more. 3 FIX32 Basic Architecture 1. Data processing: FIX is connected to hardware devices (with PLCs as a typical example), and data is obtained from the PLCs through processing workflows. 2. I/O driver, Driver Image Table (DIT), Scan, Alarm, and Control (SAC). The connection between FIX and the PLC is called an I/O driver, with different I/O drivers supporting specific PLCs. Its function is to read and write data from I/O devices and exchange data with the DIT. The rate at which the driver reads is called the polling time. The Driver Image Table (DIT) is a memory area of the node, where the I/O drivers store their data. The I/O driver will periodically update the data in the DIT. The main function of SAC is to retrieve data from DIT ； Transfer data to the process database. The rate at which SAC reads is called the scanning rate. 3. Process Database (PDB): The Process Database is the core of FIX32 and consists of process control logic loops. The description formats are Block and Chain; a block is an instruction unit within a process that can be used to specify the completion of a certain functional task. Interconnected blocks are called chains, and chains can perform monitoring or process control functions. Creating blocks in FIX32 can be achieved through the Database Builder functionality module provided by FIX32. 4. Operation display: When values are entered into the PDB, they can be displayed in a graphical format. The image display (VIEW) is an application that provides a human-machine interface for displaying data graphically. It can display alarm information, database information, and detailed information related to point names. In summary, data is retrieved from the PLC through I/O drivers and transferred to the DIT table; then, SAC reads the data from the DIT table and transfers it to the PDB. The values obtained from the PDB are then linked together and displayed graphically. This is the data flow. At the same time, the data flow can also operate in reverse; that is, the data moves from the image display device, through the PDB, to the DIT. After the I/O driver retrieves the values from the DIT, it writes them into the PLC, thereby enabling control of the device. As shown in Figure 2: Figure 2 Schematic diagram of the FIX32 data flow 4 Process of developing FIX32 1. Tasks related to the PLC: 1) When installing the FIX32 development system, it is first necessary to determine the device drivers (I/O drivers) for the hardware devices (PLC); each I/O driver supports only specific hardware. Our factory uses Japanese Mitsubishi A1S series PLCs, therefore MIT driver programs are installed. 2) Define the channels in the SCADA (Supervisory Control And Data AcQuisition) configuration within SCU (System Configuration), that is, the communication path between the configuration software and the PLC. Device definition, namely the communication device between the configuration software and the PLC. What is a query/response record definition? It refers to filling in the polling records in MIT to create a DIT (Drive Image Table). 3) Perform alarm settings, task configuration, SQL definition, and security system settings in SCU. 2. Process database definition: Based on the actual conditions of our plant, a total of 620 points have been defined, including digital input blocks (DI) for indicating the open or closed state of valves, analog input blocks (AI) for parameters such as flow rate, temperature, and turbidity, digital register blocks (DR) for control outputs, analog register blocks (AR), calculation blocks (CA), trend blocks (TR), and others. We replaced the digital output block (DO) and the analog output block (AO) with the digital register block (DR) and the analog register block (AR). Its advantage is faster reading from or writing to the PLC, as it can bypass the SAC and transfer data directly between the image display and the DIT. Reduce the workload of SAC to optimize queries and responses. The disadvantages are that it cannot issue alarms in numerical form, it cannot collect historical data, and it cannot be part of a chain. 3. Image creation: Using the toolbox and color palette provided by FIX32, realistic images can be created in the Draw program. We created a total of 15 different screens, including alum addition control, chlorine addition control, reaction and precipitation, filter tank monitoring, production data, production curves, etc. 4. Display: Using the VIEW program of FIX32, it is possible to display images containing real-time data; it establishes a connection between commands and the images, dynamically reflecting the blocks and chains in the database through those images. By having the operator sit next to the computer, they can see what changes have taken place in the production process, and the data transmitted from the process instruments provides clear information on the water quality. 5. Report generation: First, the DDE SERVER program must be started, as FIX32 uses the DDE method to export data from the FIX database to Excel in order to create reports. Then, in the properties of the Excel application, find the shortcut and add Startup.xla to it. Next, use the Report menu in Excel to create reports; it is possible to include text, real-time data, historical data, as well as information on time and date, and scheduled automatic printing can also be set up. Our factory prepares reports based on production conditions, with data being recorded every six minutes. 6. Historical curve: After creating the desired historical curve using multiple curves, it is first necessary to define historical data assignment by adding all the data blocks related to the curve in question to the historical data assignment group. Only after that can the historical data acquisition process (HTC) under Mission Control be started, thereby enabling the display of the historical curve. Our factory creates historical curves for values such as flow rate, pressure, pH level, turbidity, and residual chlorine in order to identify patterns in production, and has derived many valuable solutions from this approach. 7. Alarm function: Define alarm configurations according to actual production requirements, connect the data blocks that require alarms with animation features, and activate the alarm bell via the PLC to achieve the best alarm notification effect. 8. Remote data transmission: This involves enabling SQL support in the configuration software FIX32, establishing a corresponding relational database, and writing commands for the data items to be transmitted. In the central monitoring program, data is retrieved using programs, formatted, and stored in the local SQL server through the appropriate data interfaces, awaiting further processing. The monitoring programs developed remotely on the local network retrieve data from here. The software in the control room makes scheduled calls to the local machine, logs in to SQLSERVER, retrieves the data that has not been transmitted, and stores it in SQLSERVER on the control room’s computer, thereby facilitating future queries and statistical analysis of historical data. 9. On-site debugging: Before actual use, on-site debugging is required. Follow the principle of working from the outside in – first check the connection wires between the on-site equipment and the PLC’s inputs and outputs to ensure that the mechanical contacts are in good contact. Then verify that the DIT driver image table is correct in all aspects. Finally, test the correctness of the system’s control logic until it meets the production requirements. 5 Application Experience: Through the development of FIX32 applications and improvements during the production process. We feel that FIX32 is a configuration software designed for production processes; it comes equipped with excellent development tools. All engineering configuration tasks, including the creation of user interfaces, customization of databases, access to historical data, and control of key communication programs, are carried out in the central control room. This **reduces the time required for configuring the entire system and improves its maintainability. At the same time, through the development of FIX32, we gained a deeper understanding of its structural components and acquired many programming skills, laying a more solid foundation for future work. The above are my own experiences and insights gained while learning and using configuration software; I hope colleagues will point out any shortcomings. References: FIX Basic Course Version 104: 6.12–7.96, Intellution Company. Author profile: Wen Jinyu, female, born in 1970, of Han ethnicity; works as an automation engineer at Huizhou Water Supply Corporation, Guangdong Province. Contact numbers: 0752-2814478, 0130075270263