1. Introduction The PAC7i is a new generation of high-performance programmable automation controller launched by GE Fanuc in 2003. Its control technology is built on a standard embedded architecture, employing a general-purpose operating system and a highly integrated design. It unifies the hardware and software tools for process control, motion control, and discrete control into a single controller, enabling software programming, configuration, and diagnostics for all different hardware on a single platform. The PAC7i's advanced features and expansion technologies ensure compatibility with GE Fanuc's existing 90-70 control system. Meanwhile, the Siemens 6SE70 series frequency converter, with its comprehensive communication functions (PROFIBUS, SIMOLINK, etc.), high-precision process control functions (winding, tension, synchronization, positioning, etc.), comprehensive protection functions (overvoltage, undervoltage, overcurrent, etc.), and easy parameter setting and monitoring functions, makes the combination of these two in drive control systems an ideal system integration solution for modern control systems. This article introduces the Siemens 6SE70 frequency converter used in the oxygen lance and tilting of the converter, which is connected to the PROFIBUS-DP network of the PAC7i master station. Through PROFIBUS-DP, the master station can monitor the operating status of the frequency converter and set and change its internal parameters. 2 Hardware and software requirements for communication 2.1 Hardware requirements (1) One Advantech 610 industrial computer, Inter Pentium III, 864MHz, 256MB memory; (2) GE PAC7i PLC, equipped with SST-PFB3-VME-2 card; (3) Frequency converter with CBP2 board and CUVC board. 2.2 Software requirements (1) Win98 operating system; (2) Cimplcity Machine Edition v5.00 SP3; (3) SST PROFIBUS Configuratoin v1.9.9; (4) WABFView v1.41. 3 Basic Steps of Communication Configuration 3.1 Transmission Parameter Setting and Basic Configuration (1) Transmission Parameter Setting (Taking one unit as an example) ●p053=3 Parameter Enable (CBX board + PMU operation control panel) ●p918=1 Slave Address ●p554.1=k3001 Control Word 1 ●p443.1=k3002 Master Given Word ●p734.1=k0032 Status Word 1 ●p734.2=kk0148 Actual Speed/Frequency Value (2) PLC Configuration Board Configuration Interface See Figure 1. Basic Configuration Interface See Figure 2. PLC Hardware Configuration Interface See Figure 3. [align=center] Figure 1 Board configuration interface[/align] [align=center] Figure 2 Basic configuration interface[/align] [align=center] Figure 3 PLC hardware configuration interface[/align] ● Set the address switch of the SST-PFB3-VME-2 card according to the instructions (slot 3 in this example, S1 is off, the rest are on), restore the compression program in the board to ME (right-click "restore" in the 'Management' column). The short address depends on the switch, and the standard address depends on the programming. For example, in the program, pfb_add=14h means the standard address is "140000h". The two must be consistent when setting. ● Define the rack number, slot number, standard address, and single/dual channel flag at the beginning of the program. ● Download the configured program to PAC7i via serial port or Ethernet. ● Set the PLC run switch to the stop state. (3) Use SST PROFIBUS Configurator to configure the PLC hardware. See Figure 3 for the PLC hardware configuration interface. See Figure 4 for the configuration file transfer interface. [align=center] Figure 4 Configuration file transfer interface[/align] ● After configuration, save it. In "edit", select "export binary" to save it as a binary file; exit ● Run the wabfview.exe software, open the above binary file, and select "writebincfg" in the "file" menu. The file name must be "bincfg" and cannot be changed. (4) Download the configuration file to the plc ● Start the Windows HyperTerminal, the port is "com", and the parameters are set to the default value, "115200, 8 bits, no parity, 1 stop bit, no control" ● The plc run switch is changed from stop to run. When the board's sys light is amber, press Enter to connect. Type the command "ry", select "send file" (ymodel protocol) from the "transfer" menu, and transfer the configuration file to the board. Then type "set autorun=pfb3.ss3" to end. 3.2 Application software development part of the communication program is shown in Figure 5. The address range of the transmission device can be determined when using sst profibus configuration to configure the hardware of the plc, as shown in the attached table. After all relevant programs are written, they can be downloaded and debugged. [align=center] Figure 5 Communication Program Interface[/align] [align=center] Appendix: Address Table of Transmission Devices[/align] 4 Conclusion Through the above steps, the author established a DP network communication system with the GE PAC7i as the master station and Siemens 6SE70 series frequency converters as slave stations, realizing real-time modification of field device parameters and status monitoring. The implementation of advanced automated communication technology allows for easy integration of equipment from different manufacturers and of different types, further promoting the improvement of automation levels.