Design And Implementation Of The Monitoring System For Molten Iron Transport Based On Multilevel Network

The molten iron transport is the first part of steelmarking. It is very important. It is to ensure the normal production of steelmaking, even on the converter and blast furnace. Therefore, it is very necessary to improve the monitoring system for molten iron transport.This article is based on a transformation of the monitoring system as the background of the new system design. The original monitoring system uses the traditional field bus control system. The communication protocols in various field devices are very different which could not directly form the net, so the I/O hardwire and simple field bus are widespread used in the original system field devices. The number of cables is so high that it is susceptible to interference signals in the transmission, and difficult to achieve efficient coordination control. Combined with the system control aging in recent years, the human-computer interaction function is poor, the equipment failure rate is high, these reasons led to low productivity.So the new system adopts the control method of combining I/O hardwire and a variety of field bus control to upgrade the monitoring system. The Siemens S7-300PLC is selected as the host controller. The Profibus-DP is used in the main control network in Device performs Layer, and the Modbus is complementary. While retaining the original Profinet industrial Ethernet as high-level communication network of the system, it solves data communication problem between different protocols bus through data integration, and constitutes a multilevel network monitoring system. A variety of smart devices which dispersed in the field could communicate with the host controller directly or indirectly by their protocols. Thus it reduces a lot of I/O hardwire in the system, improves the scene of the data transmission speed and anti-interference ability, and decreases the communications equipment failure rate.This system has two on-site monitoring stations and a central monitoring station. Equipped with the monitor host machine Siemens WinCC configuration software, the software configuration environment is object-oriented directly. It only needs to configure monitoring menu, variable address and set up connections to communicate with the PLC. It uses WinCC software configuration interface, remote controlling, alarm monitoring and archiving and other functions to continuous collect data and realize real-time monitoring of field devices by remote control center.The improved monitoring system forms a complete SCADA system which could realize the real-time monitoring of production process, the operation is simple and the work is very stable. It also could make the management to achieve efficient command, scheduling and management functions. This system adapts to the requirements and development trend of modern industrial production which has broad market demand and extensive application prospect.