PLC has high requirements for reliability and software ecology:

As a control device of the production line, PLC will cause the production line to shut down once it goes down, and it is more difficult to find problems, locate problems, and repair problems than the 5501-471 execution device, and the shutdown period is long, which will bring greater losses. Especially in the use of large PLC projects, its downstream applications are mostly process industry or heavy industry, high requirements for production safety, so customers will consider the PLC manufacturer’s past success cases, especially in the verification of large projects. High reliability requirements also make the industry’s barriers high, the pattern is relatively stable and concentrated.

At the same time, the nature of the PLC is closer to the general purpose product rather than the solution, and the customer needs to conduct secondary development of the product. Development electrical engineers generally specialize in only one kind of software, and will be more inclined to choose their own familiar development software. The software used by the existing equipment is also provided by the original manufacturer, but also needs to understand the maintenance of the system engineers, software ecology throughout the whole life cycle of the PLC, which is also the main reason why Siemens occupies a large market share in the domestic automation control system. The production line shutdown or potential trial and error cost caused by PLC migration is extremely high, so ecological construction is the core competitive factor of PLC market, different industry production processes are different, PLC manufacturers should continue to deepen the industry, deepen understanding, The programming/configuration software for the small and medium-sized PLC market and the configuration software/process library for the medium and large PLC market are important moats for PLC manufacturers.

5501-471

DCS

Definition: DCS (Distributed Control System), also known as “distributed/distributed control system” or “distributed computer control system”, is composed of input and output modules, communication modules, controllers and human-machine interfaces, which are used to achieve the data acquisition, control and monitoring functions of the production process.

5501-471 Structure: DCS control system is composed of input and output module, communication module, controller and man-machine interface, which is used to realize the data acquisition, control and monitoring functions of the production process. The concept of DCS design is decentralized control, centralized management, hierarchical management, flexible configuration, convenient configuration, the corresponding implementation layer devices including all kinds of sensors, valves, instruments and so on. DCS is mainly used in chemical, petrochemical, electric power, nuclear power, pharmaceutical, metallurgy, building materials and other process industries.

Diagram: Schematic diagram of JX-300XP distributed control system

Source: Electronic enthusiast, Star Can capital collation