Abstract: This paper takes the development of a real-time monitoring system for a drawgate group as its background. Based on a description of the system's basic components, functions, and main features, it details the application and programming of Kingview 6.51 in the upper-level configuration software of this monitoring system. Keywords: Kingview; drawgate group; monitoring and control 1. Introduction This system is the drawgate group monitoring system for the Chengdu Station of the F1 Powerboat World Championship in China. The dam axis of this international competition track is 284.774m long, of which the drawgate group section is 240.4m long, with a total of 17 drawgates. The width and height of each drawgate are 12m and 4.5m respectively. This monitoring system serves an international sporting event, requiring high reliability and stability. It must be able to display real-time gate information on the monitoring host screen, such as gate height, lifting/lowering status, and fault alarms, providing operators with a clear overview of its operational status. It should also be able to store, query, and print historical data reports and operation logs. Furthermore, it requires real-time data processing to accurately acquire track water level information, and all gates must be able to accurately and promptly respond with raising, lowering, and stopping actions, ensuring that the track water level fluctuates within the small range allowed by the competition. 2. Monitoring System Structure The system's hardware mainly consists of a PLC, communication module, UPS, water level gauge, limit switch, monitoring host, display screen, and printer. KingSCADA 6.51 was used to develop the human-machine interface to implement the monitoring functions. This monitoring system adopts a hierarchical management system, and the network structure diagram is shown in Figure 1: [align=center] Figure 1 System Network Structure Diagram[/align] Each gate uses an OMRON PLC CP1H as a field control unit, and these 17 field control units constitute the local control layer. The local control layer and the main control PLC communicate via the CompoBus/S high-speed bus. The main control PLC is OMRON PLC CJ1G, which together with the monitoring host constitutes the centralized control layer. They communicate using the HostLink method. 3. Development of monitoring software based on KingSCADA Development using KingSCADA includes the following steps: (1) Define variables and connect the I/O variables of the monitoring host to the device address. (2) Design the monitoring screen, which mainly includes the operation screen, recording screen, alarm screen, etc. (3) Animation connection, establish the correspondence between screen elements and variables. (4) Construct the database, which is the core part of the monitoring system. (5) Run and debug, gradually improve the system to meet the design requirements. 3.1 Communication between the main control PLC and the monitoring host In this monitoring system, the main control PLC and the monitoring host use RS232 communication. The interface is COM1, and the device address is 0. Communication baud rate: 9600Bit/s; communication data format: 7 data bits, 2 stop bits; even parity method is used. 3.2 Monitoring System Interface and Function Implementation The monitoring system interface mainly consists of: a monitoring operation interface, a historical data recording interface, an operation record interface, an alarm interface, and a user interface. The monitoring operation interface is directly accessible to operators and primarily functions to monitor and send operation commands to the local control layer, as shown in Figure 2. The historical data recording and operation record interfaces are used to store and query various historical records. The alarm interface provides feedback to operators on the operating status of various devices, displays relevant fault information, and provides a reference for troubleshooting. The user interface serves as a "check-in" function for shift handover. In general engineering projects, each dispersed monitoring object would have an independent monitoring operation interface, resulting in numerous screens to design, a large workload, and potential for confusion and errors when defining many variables. Here, a method of referencing ordinary variables is adopted to achieve monitoring of 17 gate openings using only one monitoring operation interface. [align=center] Figure 2 Monitoring Operation Interface[/align] First, a set of memory variables related to all monitoring operations is established. This set of memory variables is used in the screen to realize the animation connection. Then, in the custom function command language provided by KingSCADA, a function ChangeVariable without a return value is defined. Finally, the VarRefAddress function in KingSCADA is used to realize the reference between ordinary variables. The ChangeVariable function is defined as follows: `Void ChangeVariable(String Open-loop and Reset Instruction, String Gate Height, String Closed-loop Setpoint, String Status Fault Information, String Title)` `VarRefAddress(\\this site\memory_Open-loop and Reset Instruction, Open-loop and Reset Instruction);` `VarRefAddress(\\this site\memory_Gate Height, Gate Height);` `VarRefAddress(\\this site\memory_Closed-loop Setpoint, Closed-loop Setpoint);` `VarRefAddress(\\this site\memory_Status Fault Information, Status Fault Information);` `\\this site\memory_Title = Title;` For example, when monitoring the operation of the eighth gate (similar for other gates), clicking the "Gate 8" button on the main monitoring interface triggers the `ChangeVariable(Open-loop and Reset Instruction_eight, Gate Height_eight, Closed-loop Setpoint_eight, Status Fault Information_eight, Title_eight)` function in the command language connection. The function associates all memory variables in the monitoring interface with the actual I/O variables defined for the eighth gate, thus making the current real-time monitoring and operation targeted at the eighth gate. This method keeps the monitoring interface unchanged while monitoring multiple similar objects, but changes the association of internal variables during monitoring operations, thereby achieving the goal of monitoring each object. This method is novel, simple, highly reliable, and greatly reduces the workload of developers. 3.3 Database Design and Report Implementation The database is the data processing center of the monitoring system and the link between the local control layer and the centralized control layer. This monitoring system requires real-time display of gate height and water levels before and after the gate, as well as operation and alarm records, all of which can generate reports, and also has query and printing functions. In this monitoring system, Windows ODBC is used to dynamically save data to the ACCESS database, and users can output query results through reports. The specific implementation steps are as follows: First, an ACCESS database is established and named "Gate Group Monitoring" in this monitoring system, and a corresponding data table "Gate Group Monitoring System" is created. Next, add a data source based on the Microsoft Access Driver in the ODBC data sources in the control panel. Name it "Racing Gate Monitoring System" in this system and connect it to the previously created Access database "Gate Monitoring". In the KingSCADA application command language, add the statement `SQLConnect(DeviceID, "dsn=Racing Gate Monitoring System")` to establish a connection with the database. Then, create the corresponding record in KingSCADA's "SQL Access Manager". After creating the record, you can use the `SQLInsert(DeviceID, "Gate Monitoring System", "Gate Monitoring System")` statement in the KingSCADA application command language's "Startup" to save the KingSCADA data to the Access database. When the system exits, the connection to the database is disconnected using `SQLDisconnect(DeviceID)`. The specific programming process is given here using a historical record report as an example. Define a `HistoryRecord` function with no return value in KingSCADA's "Custom Function Command Language": `void HistoryRecord(RealTag rTag, String Name) String GroupName; Long Time; Time = HTConvertTime("$year, "$month, "$day, "$hour, "$minute, "$second); GroupName = GetGroupName("", rTag.Group); "History_Date" = Time; "History_Date" = StrFromTime(Time, 3); "Operator" = "Username"; "Gate Name" = Name; "Gate Height" = rTag; "Gate Front Water Level" = "Gate Front Water Level"; "Gate Back Water Level" = "Gate Back Water Level";` SQLInsert(\\this site\DeviceID, "Gate Group Monitoring System", "Gate Group Monitoring System"); The monitoring system requires data to be saved to ACCESS at regular intervals. The saved data can also be queried and processed further through EXCEL. The historical data reports of this monitoring system are hourly reports, shift reports, and daily reports to meet three different query needs. The following figure shows the hourly report query result of one of the gates: [align=center] Figure 3 Data Record Report[/align] The operation record report mainly records the specific operation of the operators, such as the login and departure time of the duty personnel, what operations were performed on the gates, and what control signals were sent to the local control layer. The alarm report mainly records various alarm events and alarm status values ​​during system operation, and alarm priority and alarm threshold can be set according to the severity of the events. The generation and query functions of operation reports and alarm reports are similar to the historical record reports above. 4. Conclusion and Innovation of this paper This monitoring system is developed using Kingview 6.51 as the development platform for real-time monitoring of river dam gate groups. It realizes functions such as real-time monitoring, fault alarm, storage and query of historical data, and display and printing of reports. It accurately and objectively reflects the real-time operation status of the gate group. The data refresh speed is fast and the accuracy is high. The operation interface is simple and has a user-friendly human-computer interaction interface. Since the system was put into use, the operation status has been safe, stable and reliable, and it has won high praise from users. It played an important role in the F1 Powerboat World Championship Chengdu Station in October 2006. The main innovations of this paper are: (1) In the design of the upper computer configuration software, one interface is used to monitor multiple similar objects, which overcomes the drawback of repeated design of monitoring interfaces in general engineering. (2) The method of referencing ordinary variables has a novel aspect in I/O variable animation connection. (3) The database design method is simple and efficient. It does not need to use professional SQL, Oracle and other large databases to meet the system requirements, saving development costs. References: [1] Beijing Yacon Technology Development Co., Ltd. Kingview 6.51 User Manual. 2005.11 [2] Lin Yong, Yu Yongquan. Application of Kingview in Industrial Boiler Soot Blowing System. Microcomputer Information. 2004.9 [3] Gong Rong, Li Hongsheng. Application of Kingview 6.5 in Oil Well Real-time Monitoring System. Industrial Control Computer. 2005.7 [4] Zhong Lingling, Zhou Haomin. Water Pressure Control System Based on Kingview 6.5 and PLC. Automation and Instrumentation. 2006.4