Design Of Sheathing Line Control System For Optic Fiber Cables Based On Field-bus

At present, China's production and demand for optic fiber cables rank the third in the world. There's an increasingly high demand for performances of various optic fiber cables all over the world. Sheathing line for optic fiber cables is the last step in optic fiber cable's manufacturing industry. The quality of the sheathed cable will have a crucial impact on cable's mechanical, thermal, chemical and other properties.The thesis focuses on the reconstruction project of sheathing line, thus designs a control system based on PROFIBUS-DP field-bus. In the overall structure, the sheathing line control system uses industrial control computer (IPC)+Programmable Logic Controller (PLC)+PROFIBUS-DP field-bus as the overall framework. On the one hand, aiming at many decentralized I/O points, the system applies distributed control strategy. On the other hand, centralized management control may be effective for handling with the complexity of the production process, a wide variety of control equipment. This control system is of great pertinence.In hardware design, we choose Siemens S7-300 series PLC as DP master, and make use of S7-200 series PLC as DP slaves. Through the PROFIBUS-DP field-bus network, DP master can communicate with each DP slave. The control objects of DP master and DP slaves are relatively independent which brings an increase in control precision and reliability. Field-bus, working as a bridge between master and slaves, increases data transmission rates and the openness of the system. The hardware design of the system makes the advantages and characteristics of field-bus based distributed control system, "decentralized control, centralized management", into full play.In software design, the control system adopts Siemens STEP7 programming software in the network configuration for both master and slaves, and parameter configuration for CPUs which sets up a PROFIBUS-DP field-bus network structure. Then the thesis makes a detailed analysis and discussion of single master host controlling, extruder temperature control algorithm, meters counting, and completes the program design of corresponding parts. Hardware and software reach mutual coordination and harmonization.The system uses Advantech's industrial control computer as the host operating station. "InTouch" configuration software is used to design a production process monitoring, important parameter display, accident alarm processing, report printing and other features archive interface. The interactive system is user-friendly, easy to operate and full of power.