Profibus Technology and its application in the electronic control system of tobacco spinning
as a bus standard, PROFIBUS has the characteristics of openness, internationalization and independence from equipment manufacturers. The compatible network system composed of PROFIBUS can be used in different occasions, including profibus-fms, which provides powerful communication function; PROFIBUS-DP is used for high-speed data transmission at the sensor and actuator levels; Profibus-PA is used in high security occasions, allowing complete internal operation of the equipment
in the electronic control system of tobacco spinning, most of the control objects are switching points. PROFIBUS-DP is used for field equipment control, and Siemens Industrial Ethernet or profibus-fms is generally used for communication between master stations
in this paper, we will take the most widely used mode as an example, that is, the main station monitoring level network adopts Siemens Industrial Ethernet, and the device level network adopts PROFIBUS-DP
electronic control system equipment and structure configuration
when selecting field level control equipment, we mainly consider choosing one of Siemens' Profibus and another's bus. Because the electric control system of wire making is mainly composed of motor control circuit, the technology of another company requires that each motor control as its sub station, the cost is higher than that of many integrated load feeders of ET200S in Siemens PROFIBUS-DP family, which combines the input/output of PLC, terminal modules, circuit breakers and contactors, Theoretically, each DP slave station can control up to 20 motors (the physical length of each sub station cannot exceed 1 meter, and the physical width of the load feeder is 45mm). In this sense, ET200S is the best choice. Another reason is that the products of Siemens are still the most widely used control systems in the tobacco industry. Therefore, the type selection of field level control equipment is determined as ET200S product
according to the requirements of silk making process, the whole line is divided into twelve process sections, and each process section is controlled by a group of PLC. In the PLC of each process control section, the master station adopts s product, and the CPU type is the CPU with built-in DP port. Its system structure is shown in the figure
according to the above design principles, fieldbus technology has been successfully applied in the silk making electronic control system of a tobacco factory. We have adopted 8 groups of PLC control, and the field device control adopts PROFIBUS-DP mode to form 8 groups of PROFIBUS-DP respectively. There are 61 motor ET200S stations, 81 general i/o stations, 67 frequency converter stations, 8 operator stations, 18 moisture meter stations, 18 electronic scale stations and 7 console stations
system features
after using Profibus Technology, compared with the traditional electronic control system, the system has the following characteristics:
the system design is more convenient and clear, and the use of load feeders eliminates the design of motor protection switches, contactors, and a large number of schematic diagrams and wiring diagrams with PLC input/output, which greatly reduces the amount of drawings. The use of ET200S modular components also makes the wiring and design in the cabinet (box) simpler, The design and production cycle of the control system are accelerated
the installation is simple and fast. Without using any tools, the interface module and terminal module are stuck on the guide rail. After the wiring is completed, the electronic module, power module and load feeder module "plug and play"
it is easier to configure and debug without other special software. In the S7 software package, you can complete the configuration of PROFIBUS-DP by dragging with the mouse. Without extra cost, equipment faults can be reported through the bus, making fault location more convenient
simple maintenance
the use of sub stations and modular components is divided into three types: manual wood-based panel universal experimental machine and powerful fault diagnosis ability, which will bring great convenience to equipment maintenance in the future
convenient for expansion and information integration
p Jinan assay refuels for the Paralympic Games. The use of PROFIBUS brings isolated unit equipment into the information network, laying a good foundation for the future system expansion and the realization of enterprise integrated automation
end user engineering cost reduction
the use of Profibus Technology saves a lot of cables, bridges, terminal strips, cabinets, etc., training and maintenance costs are strengthened, and the fixed-point, fixed-time and fixed-time ship use of Qiongzhou Strait ferry transportation are reduced, which all reduce the total engineering cost. If it is necessary to carry the electronic universal testing machine. The following table shows the comparison of materials used in the electronic control system of typical silk making line
conclusion
profibus technology has been successfully applied in the tobacco industry since 1999, especially in the 6000kg/h silk production control system of a tobacco factory in Jiangsu Province, Profibus Technology is used in the control of field equipment, which has been highly praised by users. Especially compared with traditional centralized control, it has obvious advantages in system design, installation, debugging, maintenance and expansion. The successful application of profi bus technology in the tobacco industry is of typical significance. It provides an ideal solution for automation projects in other industries and should be widely promoted
author unit: Far East Company
address: tuying village, Dachang County, Hebei Province 065300
email:laobing221@ (end)
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