1. Introduction to Industrial Ethernet The so-called Industrial Ethernet is generally referred to as technically compatible with commercial Ethernet (ie, the IEEE 802.3 standard), but in product design, the choice of materials, strength, suitability, and real-time Sex, interoperability, reliability, anti-jamming and intrinsic safety can meet industrial site requirements.
2. Characteristics of Industrial Ethernet 2.1 Real-time and determinism With the development of Fast Ethernet and Switched Ethernet technology, new uncertainties have been brought about to solve the non-deterministic problem of Ethernet, making this application possible. . First, the communication speed of Ethernet has increased from 10M and 100M to today's 1000M and 10G. Under the same conditions of data throughput, the increase of communication speed means the reduction of network load and the reduction of network transmission delay, that is, the network. The probability of collision is greatly reduced. Secondly. The star network topology is used instead of the bus structure, and the switch divides the network into several network segments. Because of the data storage and forwarding functions of the Ethernet switch, the input and output data frames between ports can be buffered and no collision occurs. At the same time, the switch can also filter the data transmitted on the network so that each network segment can be filtered. The transmission of data between nodes is limited to the local network segment, without going through the backbone network and occupying the bandwidth of other network segments. This reduces the network load of all network segments and backbone networks.
Again, full-duplex communication allows the two frames of twisted pair (or two fibers) between the ports to simultaneously receive and send message frames at the same time without conflict. Therefore, using switching hubs and full-duplex communications, the conflict domain on the network no longer exists (full-duplex communication), or the collision probability is greatly reduced (half-duplex), so the Ethernet communication is deterministic and true Greatly improve.
2.2 Stability and Reliability Another major problem with Ethernet entering process control is that the connectors, hubs, switches, and cables used in the process are designed for commercial applications. Commercial networking products cannot be used for higher reliability. In the harsh industrial field environment required, Industrial Ethernet must be designed for the harsh industrial field environment (such as redundant DC power input, high temperature, low temperature, dustproof, etc.).
With the development of network technology. The above problems are being quickly resolved. In order to solve the problem of uninterrupted industrial applications and the stable operation of the network under extreme conditions, Synergetic Microsystems USA and Hirschmann and Jetter AG of Germany have specially developed and produced rack rail hubs and switches for installation. Standard DIN rail and powered by a redundant power supply, the connector uses a robust DB29 structure. There are now industrial devices (such as PLCs, HMIs, DCS systems, etc.) that have been specially designed to connect with Ethernet interfaces in industrial applications.
In addition, in practical applications, the backbone network can be transmitted using optical fibers, and the field device can be connected using shielded twisted pair cables. For important network segments, redundant network technology can also be used to improve the anti-interference ability and reliability of the network. .
3. Metallurgical Automation Control System Architecture According to the current popular automation architecture, typical metallurgical automation systems can be divided into four levels: basic automation system, process control system, production management control system, and enterprise information system.
3.1 Basic automation system Computer control represented by PLC, DCS, industrial control computer is based on the control of field-level equipment. In the basic automation system, the current PLC control still dominates: In the metallurgical process, the basic automation control system is a key part. It does not directly affect the entire control system.
3.2 Process Control System Metallurgical process online continuous detection and monitoring system. Adopt new sensor technology, optical-mechanical integration technology, soft measurement technology, data fusion and data processing technology, reliability technology in metallurgical environment, closed-loop control of key process parameters, logistics tracking, energy balance control, real-time environmental emission control and product quality Full process control is the goal. Metallurgical process online detection and monitoring system.
3.3 Production Management Control System Holographic integration of metallurgical processes. Realize the horizontal data integration and mutual transmission of iron-steel rolling, realize management rarr; plan rarr; production rarr; control vertical information integration. Colleagues integrated production of real-time data and relational databases into data warehouses, used data mining techniques, and provided decision support for production management control.
3.4 Enterprise Information System Integration of enterprise information into industry information integration. One of the purposes of informatization is to realize information sharing, and seek advantages and avoid disadvantages under the premise of effective competition. On the basis of the standardization of the coding system of enterprise information systems and heterogeneous data/information integration of enterprises, the information integration of collaborative manufacturing enterprises is further realized. Information network construction and macro control information system, direct military global industry information network construction and macro-control information system.
4. Network structure of automation control system and network communication 4.1 Network structure of automation control system From on-site level to production control level, and then to the corporate management network structure can be designed using a variety of different types of networks, currently used most It is the Siemens Profibus network that is mostly used in the field of industrial Ethernet, but Siemens' Profinet network (which combines Ethernet and Profibus) is a newly developed field-level network. In the future, it will gradually replace the Profibus network, and most of the three-tier control systems above the field level use Ethernet.
Ethernet plays an important role in the automation control system. The field level network in the basic automation system adopts Profibus (the most widely used) or Profinet is the most popular and practical network at present. But Profinet networks are much better than Profibus networks because Profinet is based on Ethernet, so Profinet later caught up.
The control system above the field level adopts industrial Ethernet, and each level of industrial Ethernet can adopt different structures such as: ring structure, tree structure and so on. All Ethernet interface devices can be connected to the Ethernet network through exchanges of hunger, hubs, and routers. In order to ensure the smoothness of the network and the stability and reliability of the system, it is recommended that all control systems use ring networks or do redundant systems.
4.2 Ethernet network communication of automation system 4.2.1 Ethernet communication between PLC and PLC Here take Siemens S7-3001400 series PLC as an example. PLC can use S7 communication, S5mdash; compatible communication (including ISO protocol, TCP negotiation, ISOmdash; on-TCP protocol, etc.), the following introduces several common communication methods.
Required hardware: 2 sets of S7-300 system (including power supply module PS307, S7-300PLC, Ethernet communication module CP343mdash; 1), PC, Ethernet communication network card CP1613 and connection cable. Required software: STEP7.
1S7 Communication Use STEP 7 software for hardware configuration and network configuration (establishing an S7 connection) and writing communication programs. If you choose to use bilateral communications, you must write communication programs on both sides of the PLC. The S7-300 PLC calls the functions FB12, FB13 for communication. The S7-400 calls the functions SFB12 and SFB13 for communication; if unilateral communication is selected, the active party only writes the communication program, and the S7-300 PLC calls FB14 and FB15 for communication. The S7-400 calls the functions SFB14, SFB15 for communication.
2TCP Communication Use STEP 7 software for hardware configuration and network configuration (establishing a TCP connection) and writing communication programs. Both PLCs write communication programs. The S7-300 PLC calls the functions FC5 and FC6 for communication, and the S7-400 calls the functions FCSO and FC60 for communication.
3ISO Communication Use STEP 7 software for hardware configuration and network configuration (establishing an ISO connection) and writing communication programs. Both PLCs write communication programs. S7-300 PLC calls functions FC5 and FC6 to communicate. S7-40o calls functions FC50 and FC60 to communicate.
The operation methods of the above three communication methods are basically the same. Only when the connection is established, the respective protocols can be selected.
4.2.2 Ethernet Communication between PLC and HMI Because there are many kinds of monitoring software in the upper computer, the communication between the PLC and the HMI is also very diverse. Different PC monitoring products may have different communication protocols with PLC. However, most monitoring software has a common standard interface: the OPC interface, so most of the Ethernet communication between PLC and HMI can use OPC to communicate. In addition, users can also use VC, VB and other programming software to develop some simple monitoring interfaces with Siemens PLC for direct TCP communication.
Hardware required for 1OPC communication: 1 set of S7-3o0 system (including power supply module Ps307, S7-300PLC, Ethernet communication module CP343mdash; 1), PC, Ethernet communication network card CP1613 and connection cable. Required software: STEP7, SIMATIC NET6.3f provide virtual Pc machine and parameter setting for Pc station), Kingview Ethernet communication implementation: Hardware configuration and network configuration using STEP7 software and virtual PC configuration using HIMATICNET . Create the required variables in the OPC SCOUT provided by the SIMATIC NET software and add them to the list to check their quality stamps. If it is good, the configuration is successful; if it is bad, the configuration fails. Set up OPC communication interface in the upper computer monitoring software, and establish external variables. Select the established OPC interface in the connected device of the variable, and select the variable created in OPCSCOUT in the register of the variable, so that the communication between the PLC and the monitoring software of the host computer HMI is realized through the OPC interface. If you do not use the upper monitoring software can also be achieved through the use of VC, VB application written and read OPCSCOUT established variables.
2 TCP/IP communication between the application program written in VB and Siemens PLC. Required hardware: 1 set of S7-300 system (including power supply module PS307, S7-300 PLC, Ethernet communication module CP343mdash; 1), PC, general Computer Ethernet communication network card and connecting cable. Required software: STEP7, VB.
Ethernet communication implementation: Hardware configuration with STEP 7 software and network configuration (establishing a TCP connection) and virtual PC configuration with SIMATIC NET. (Set up TCP connection) Write communication program, write communication program on PLC side, S7mdash; 300PLC call function FC5, FC6 for communication, S7-400 call function FC50, FC60 for communication, on HMI side write communication program with VB, use Winsock Controls to achieve.
5. Summary The network structure and network communication in industrial Ethernet are the core parts of the automation control system. Therefore, for each automation control system, whether the design of the network structure and network communication is ideal or not determines the performance of the system directly. . Since industrial Ethernet technology has demonstrated the beauty of industrial control informatization, that is, it can be extended to the enterprise field device control layer, it is generally considered to be the best solution for controlling the network in the future. Industrial Ethernet has been Become the leading edge technology in fieldbus.
2. Characteristics of Industrial Ethernet 2.1 Real-time and determinism With the development of Fast Ethernet and Switched Ethernet technology, new uncertainties have been brought about to solve the non-deterministic problem of Ethernet, making this application possible. . First, the communication speed of Ethernet has increased from 10M and 100M to today's 1000M and 10G. Under the same conditions of data throughput, the increase of communication speed means the reduction of network load and the reduction of network transmission delay, that is, the network. The probability of collision is greatly reduced. Secondly. The star network topology is used instead of the bus structure, and the switch divides the network into several network segments. Because of the data storage and forwarding functions of the Ethernet switch, the input and output data frames between ports can be buffered and no collision occurs. At the same time, the switch can also filter the data transmitted on the network so that each network segment can be filtered. The transmission of data between nodes is limited to the local network segment, without going through the backbone network and occupying the bandwidth of other network segments. This reduces the network load of all network segments and backbone networks.
Again, full-duplex communication allows the two frames of twisted pair (or two fibers) between the ports to simultaneously receive and send message frames at the same time without conflict. Therefore, using switching hubs and full-duplex communications, the conflict domain on the network no longer exists (full-duplex communication), or the collision probability is greatly reduced (half-duplex), so the Ethernet communication is deterministic and true Greatly improve.
2.2 Stability and Reliability Another major problem with Ethernet entering process control is that the connectors, hubs, switches, and cables used in the process are designed for commercial applications. Commercial networking products cannot be used for higher reliability. In the harsh industrial field environment required, Industrial Ethernet must be designed for the harsh industrial field environment (such as redundant DC power input, high temperature, low temperature, dustproof, etc.).
With the development of network technology. The above problems are being quickly resolved. In order to solve the problem of uninterrupted industrial applications and the stable operation of the network under extreme conditions, Synergetic Microsystems USA and Hirschmann and Jetter AG of Germany have specially developed and produced rack rail hubs and switches for installation. Standard DIN rail and powered by a redundant power supply, the connector uses a robust DB29 structure. There are now industrial devices (such as PLCs, HMIs, DCS systems, etc.) that have been specially designed to connect with Ethernet interfaces in industrial applications.
In addition, in practical applications, the backbone network can be transmitted using optical fibers, and the field device can be connected using shielded twisted pair cables. For important network segments, redundant network technology can also be used to improve the anti-interference ability and reliability of the network. .
3. Metallurgical Automation Control System Architecture According to the current popular automation architecture, typical metallurgical automation systems can be divided into four levels: basic automation system, process control system, production management control system, and enterprise information system.
3.1 Basic automation system Computer control represented by PLC, DCS, industrial control computer is based on the control of field-level equipment. In the basic automation system, the current PLC control still dominates: In the metallurgical process, the basic automation control system is a key part. It does not directly affect the entire control system.
3.2 Process Control System Metallurgical process online continuous detection and monitoring system. Adopt new sensor technology, optical-mechanical integration technology, soft measurement technology, data fusion and data processing technology, reliability technology in metallurgical environment, closed-loop control of key process parameters, logistics tracking, energy balance control, real-time environmental emission control and product quality Full process control is the goal. Metallurgical process online detection and monitoring system.
3.3 Production Management Control System Holographic integration of metallurgical processes. Realize the horizontal data integration and mutual transmission of iron-steel rolling, realize management rarr; plan rarr; production rarr; control vertical information integration. Colleagues integrated production of real-time data and relational databases into data warehouses, used data mining techniques, and provided decision support for production management control.
3.4 Enterprise Information System Integration of enterprise information into industry information integration. One of the purposes of informatization is to realize information sharing, and seek advantages and avoid disadvantages under the premise of effective competition. On the basis of the standardization of the coding system of enterprise information systems and heterogeneous data/information integration of enterprises, the information integration of collaborative manufacturing enterprises is further realized. Information network construction and macro control information system, direct military global industry information network construction and macro-control information system.
4. Network structure of automation control system and network communication 4.1 Network structure of automation control system From on-site level to production control level, and then to the corporate management network structure can be designed using a variety of different types of networks, currently used most It is the Siemens Profibus network that is mostly used in the field of industrial Ethernet, but Siemens' Profinet network (which combines Ethernet and Profibus) is a newly developed field-level network. In the future, it will gradually replace the Profibus network, and most of the three-tier control systems above the field level use Ethernet.
Ethernet plays an important role in the automation control system. The field level network in the basic automation system adopts Profibus (the most widely used) or Profinet is the most popular and practical network at present. But Profinet networks are much better than Profibus networks because Profinet is based on Ethernet, so Profinet later caught up.
The control system above the field level adopts industrial Ethernet, and each level of industrial Ethernet can adopt different structures such as: ring structure, tree structure and so on. All Ethernet interface devices can be connected to the Ethernet network through exchanges of hunger, hubs, and routers. In order to ensure the smoothness of the network and the stability and reliability of the system, it is recommended that all control systems use ring networks or do redundant systems.
4.2 Ethernet network communication of automation system 4.2.1 Ethernet communication between PLC and PLC Here take Siemens S7-3001400 series PLC as an example. PLC can use S7 communication, S5mdash; compatible communication (including ISO protocol, TCP negotiation, ISOmdash; on-TCP protocol, etc.), the following introduces several common communication methods.
Required hardware: 2 sets of S7-300 system (including power supply module PS307, S7-300PLC, Ethernet communication module CP343mdash; 1), PC, Ethernet communication network card CP1613 and connection cable. Required software: STEP7.
1S7 Communication Use STEP 7 software for hardware configuration and network configuration (establishing an S7 connection) and writing communication programs. If you choose to use bilateral communications, you must write communication programs on both sides of the PLC. The S7-300 PLC calls the functions FB12, FB13 for communication. The S7-400 calls the functions SFB12 and SFB13 for communication; if unilateral communication is selected, the active party only writes the communication program, and the S7-300 PLC calls FB14 and FB15 for communication. The S7-400 calls the functions SFB14, SFB15 for communication.
2TCP Communication Use STEP 7 software for hardware configuration and network configuration (establishing a TCP connection) and writing communication programs. Both PLCs write communication programs. The S7-300 PLC calls the functions FC5 and FC6 for communication, and the S7-400 calls the functions FCSO and FC60 for communication.
3ISO Communication Use STEP 7 software for hardware configuration and network configuration (establishing an ISO connection) and writing communication programs. Both PLCs write communication programs. S7-300 PLC calls functions FC5 and FC6 to communicate. S7-40o calls functions FC50 and FC60 to communicate.
The operation methods of the above three communication methods are basically the same. Only when the connection is established, the respective protocols can be selected.
4.2.2 Ethernet Communication between PLC and HMI Because there are many kinds of monitoring software in the upper computer, the communication between the PLC and the HMI is also very diverse. Different PC monitoring products may have different communication protocols with PLC. However, most monitoring software has a common standard interface: the OPC interface, so most of the Ethernet communication between PLC and HMI can use OPC to communicate. In addition, users can also use VC, VB and other programming software to develop some simple monitoring interfaces with Siemens PLC for direct TCP communication.
Hardware required for 1OPC communication: 1 set of S7-3o0 system (including power supply module Ps307, S7-300PLC, Ethernet communication module CP343mdash; 1), PC, Ethernet communication network card CP1613 and connection cable. Required software: STEP7, SIMATIC NET6.3f provide virtual Pc machine and parameter setting for Pc station), Kingview Ethernet communication implementation: Hardware configuration and network configuration using STEP7 software and virtual PC configuration using HIMATICNET . Create the required variables in the OPC SCOUT provided by the SIMATIC NET software and add them to the list to check their quality stamps. If it is good, the configuration is successful; if it is bad, the configuration fails. Set up OPC communication interface in the upper computer monitoring software, and establish external variables. Select the established OPC interface in the connected device of the variable, and select the variable created in OPCSCOUT in the register of the variable, so that the communication between the PLC and the monitoring software of the host computer HMI is realized through the OPC interface. If you do not use the upper monitoring software can also be achieved through the use of VC, VB application written and read OPCSCOUT established variables.
2 TCP/IP communication between the application program written in VB and Siemens PLC. Required hardware: 1 set of S7-300 system (including power supply module PS307, S7-300 PLC, Ethernet communication module CP343mdash; 1), PC, general Computer Ethernet communication network card and connecting cable. Required software: STEP7, VB.
Ethernet communication implementation: Hardware configuration with STEP 7 software and network configuration (establishing a TCP connection) and virtual PC configuration with SIMATIC NET. (Set up TCP connection) Write communication program, write communication program on PLC side, S7mdash; 300PLC call function FC5, FC6 for communication, S7-400 call function FC50, FC60 for communication, on HMI side write communication program with VB, use Winsock Controls to achieve.
5. Summary The network structure and network communication in industrial Ethernet are the core parts of the automation control system. Therefore, for each automation control system, whether the design of the network structure and network communication is ideal or not determines the performance of the system directly. . Since industrial Ethernet technology has demonstrated the beauty of industrial control informatization, that is, it can be extended to the enterprise field device control layer, it is generally considered to be the best solution for controlling the network in the future. Industrial Ethernet has been Become the leading edge technology in fieldbus.
Baby Bibs Silicone Waterproof,Silicone Bibs For Baby,Bibs For Kids,Food Grade Bibs
Taizhou Huangyan New Vision Indsutry & Trading Co.,Ltd , https://www.super-factories.com