What should be paid attention to when industrial switches are used in factories!

​Industrial switches are also called industrial Ethernet switches, that is, Ethernet switch devices used in the field of industrial control. Due to the adopted network standards, they are open, widely used, and inexpensive, and use transparent and unified TCP/IP Protocol, Ethernet has become the main communication standard in the field of industrial control. Because the environment of the factory is generally harsh, if you use an industrial switch in the factory, you must understand the precautions for using the industrial switch.

1. Ethernet network layout

The network topology of the office is not suitable for the production floor of the factory, where the Ethernet topology of the factory/machine is used. Unlike office Ethernet infrastructures, which are usually built with commercial-grade products that function well in a constant-temperature environment and in a star-topology switched network, industrial Ethernet architectures often face multiple Unforeseen circumstances, it needs to have some additional functions, such as high-speed redundancy. Industrial Ethernet will adopt a variety of topological network layout methods (star, ring, tree, and line), and use shielded cables and metal connectors, which have higher heat and shock resistance. In addition, industrial switches are generally configured and maintained by the corresponding automatic control system integrators.

2. Ethernet communication protocol

For control system integrators, the most important thing is to realize that Ethernet is just a network architecture. To enable it to communicate between automatic control devices, you need an industrial-grade communication protocol. The IEEE802.3 Ethernet standard defines the wiring method, data read and write rules and the structure of the Ethernet architecture. Although different devices using this network standard can communicate in the same network segment, the prerequisite is that they must use the same network protocol, or "communication language". Profinet is a communication protocol designed for industrial applications. It provides functions for distributed I/O, machine-to-machine connectivity, machine safety, and motion control.

3. The processing power of Ethernet

It's not simply about how fast the network is, but how quickly and precisely the data gets to where it's supposed to go. The processing power of the network is undoubtedly one of the most critical factors, and its measurement standard is the amount of network data transmission per unit time. And the only way to improve this performance is to reduce the number of cycles in the communication stack. The number of cycles in the Profinet communication stack is ten times less than that of a standard Ethernet TCP/UDP implementation. This is due to the fact that Profinet has set up an Ethernet real-time channel for some important work with strict requirements on time, while at the same time, its configuration, diagnostics, routing and "bulk data transmission" communications are all via standard TCP/ The IP channel is complete.

4. Ethernet network configuration

The setting of the network is simple on the one hand, but more importantly, the programming work to realize the communication must not be too complicated. Profinet enables communication between devices through configuration rather than programming. System integrators and end users can save at least 25% of the construction and commissioning time through a method of configuring internal communication between devices that corresponds to objects, rather than the traditional method of programming and debugging.

5. Early planning

It is not enough to only consider the immediate application, the current Ethernet must be able to meet the needs of all possible applications in the future. Profinet enables users to implement a highly integrated system suitable for different control functions (such as point-to-point communication, distributed I/O, machine safety, motion control, and data acquisition) at their own pace, using only a single Ethernet network. ) of the automatic control system. It also provides for possible future extensions.

6. Renovation of the old system

The elements of industrial Ethernet are not limited to Ethernet itself. How to integrate and work normally with existing networks and machines provided by different suppliers is one of the issues that must be considered. Since Profinet uses standard industrial switches and uses TCP/IP protocol components, the Profinet-based system should be applicable to the entire self-control network without additional high-end industrial switches or special functions, such as IGMP snooping and VLAN. Profinet also provides solutions for connecting products from different suppliers to the same network. Through XML, it treats each machine as a component, which is relatively independent of the internal core control system. This is the automation concept with components as control units.

7. Fees

For industrial Ethernet networks, the most important expense is not the components that build the network, but the design, installation and maintenance. Profinet and other similar industrial Ethernet frameworks use the achievements of IT technologies, such as OPC and SNMP, to monitor and display the status of the network. In addition, its diagnostic function can directly reflect the state of the network on the automatic control system including plc and SCADA system. In this way, both configuration setting and fault finding can be completed in the central control room, which greatly simplifies the operation.