The intelligent factory is a new stage in the development of factory information. With the wide application of automation systems in manufacturing enterprises, the factory is gradually moving towards Industry 4.0. Realizing Industry 4.0 requires a high degree of industrialization and automation, and it is a long journey. Regardless of the extent to which smart manufacturing is developed, data collection is the most practical and high-frequency requirement in production and a prerequisite for Industry 4.0.

A digital factory is not equal to an unmanned factory. The product configuration and manufacturing process are more complex and more varied, and the more people need to participate. In the digital factory, workers are more likely to handle abnormal situations and adjust equipment. Data acquisition applications based on bar code and RFID have been widely used in existing MES systems, but many automated devices lack effective connections, and MES systems and automation devices form information islands. Driving automation with information technology is an effective way to realize smart factories. Qingdao Hongzhi is committed to the development and application of data acquisition system modules for Industry 4.0, and has integrated several specific applications in actual projects. Based on our technical accumulation, let's talk about the implementation of equipment data collection.

The variety of equipment in the manufacturing workshop is diversified, and the implementation of equipment condition monitoring is particularly cumbersome. How to obtain the production status information of various brands and different communication protocol equipments in the most efficient way under limited cost, and transfer the data to the management system for further analysis and remote monitoring control, and improve the efficiency of process monitoring. It also saves operating and maintenance costs, which will be a major challenge for managers. The field device data acquisition system is the information link between the field automation control equipment and the upper MES system. There are many equipments and interfaces in the factory. How to realize equipment communication becomes a difficult point. A technical basis for implementing MES is to communicate with field devices to achieve automated data collection. This article starts with the general equipment communication of the factory, and introduces the digital mining communication scheme of the smart factory.

1. PLC communication scheme

The production line and many intelligent devices adopt PLC control. The basic priority of PLC control data acquisition is as follows: PLC network port>PLC serial port. The specific suggestions are as follows:

1. PLC control system with Ethernet interface, if you can use Ethernet interface, you can directly use Industrial Ethernet access. The typical case of the Shenyang Haier refrigerator project foaming equipment is to use the Ethernet port to obtain the equipment operating parameters directly from the Siemens PLC. The Hefei Phase II information project uses the Ethernet port to directly take the second phase of the external line from the Mitsubishi Q series PLC. Run status parameters. However, it is necessary to pay attention to the PLC control system with the Ethernet interface. If the existing Ethernet interface is used for communication, the IP address of the Ethernet device connected to this connection needs to be modified first, and then the industrial Ethernet is used for access. Devices involved in modifying the IP address may have PLC control systems, touch screens, host monitoring computers, inverters, servo drives, and so on.

(Mitsubishi Q series PLC uses the CPU's own network port to access the network)

2. For an Ethernet-free interface, it can be accessed by Industrial Ethernet through a system that adds an Ethernet port. For example, the Siemens S7-300 can be expanded by adding the CP343 module. The Mitsubishi Q series can be added with the extended QJ71 module. The Mitsubishi FX3u series can be extended to extend the FX3U-ENET module for Ethernet access. Specific project case: The first phase of the Hefei Informatization Project is the Mitsubishi Q series PLC to increase Ethernet communication by adding QJ71 expansion module; the Hefei Informatization Project Phase II perfusion system is the Mitsubishi FX3u series by adding the expansion FX3U- The ENET module implements Ethernet communication.

(The FX3u series can be expanded with the FX3U-ENET module for Ethernet access)

3. For devices that cannot expand the Ethernet interface or Ethernet has been occupied, but can use the original 232 communication interface, you can directly use the original PLC communication interface and convert the system to the Ethernet interface through the serial port server. The typical case of the Jiaozhou two-machine and Wuhan two- piece punching machine part of the equipment is to use the communication port of the equipment to connect to the serial port server into a network port access system.

(FX3u directly uses the PLC communication port and the serial port server to connect to the network port and access the network)

4. If the control system does not have the communication acquisition capability, consider extending the existing control system out of the 232 communication interface, and then transferring it to the Ethernet interface through the serial port server. Its typical case is that the Mitsubishi FX3U series realizes 232 serial communication by adding the extended FX3U-232ADP module, and then connects the serial port to the system through the serial port server.

(FX3u adds extended FX3U-232ADP module for serial communication)

2. Intelligent instrument and automatic device communication scheme

1. The smart meter equipped with Modbus RTU interface is connected through RS485 shielded cable, and then connected to the system through the serial port server to convert the network port. In order to ensure the stability of data communication and the real-time nature of data transmission, the number of instruments connected to a communication bus should not exceed 10. The typical case is the Hefei Phase II information project, which reads the pumping equipment and the weighing instrument.

2. There are some instruments that only support custom protocols. We can only access the serial server according to the wiring method provided by the manufacturer and then switch to the network port to access the system. The agreement was developed according to the manufacturer's agreement.

3. Some smart devices have a special interface system, and interfaces such as WEB services, databases, interface functions, etc. are used. The MES system can exchange information with the equipment through the interface system to achieve the docking target.

In summary, the plant's data acquisition communication plan should first clear the requirements, that is, we need to clearly collect which data (start and stop status, fault status, quantity, temperature, pressure, model, etc.), and secondly need to know the field equipment (product model) , support agreement, network port, communication port, etc., according to the situation of the field equipment to make choices, the method is not unique, this article is just tossing jade, we need specific analysis of specific problems, using different ideas to solve specific problems. With the gradual advancement of the Industry 4.0 system, more digital mining modules will be networked and applied. We will continue to carry forward the craftsman spirit and do the fine engineering of the number mining!