Open should mean Open

Yes, you can model Linux to work in an automation environment

Automation system users need the latest interoperable architectures that provide high performance and highly available controls. This much is known. The systems must be highly flexible and able to control the entire plant, transfer information, and provide places to store history and information. In addition, users want greater flexibility to modify without shutting down and the ability to network easily to existing and future control components.

In the past, a distributed control system (DCS) and programmable logic controllers (PLC) would have been the only means to apply those types of control applications. You could network these older systems together, and then an engineer would have to manually route each point, which costs a user time and money. On top of all that, a huge amount of time would be necessary to install and set up special cables and hardware to connect the systems to work as one.

But the days of DCSs and PLCs being the only game in town are going away. In just about any industry, if a manufacturer uses open networks like Linux, fieldbuses and protocols can provide a common functionality that will provide an easy transportable solution to any suppliers' product. The biggest advantage is it gives the necessities of the industry but limits the cost to users. Consequently, standardized networks reduce the installation time, training, and global acceptance of the technology, which can only promote installation of new networks and help in reducing maintenance and support costs.
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Bus technology

A fieldbus bus network is a digital serial two-way communication bus that connects control and field devices. Fieldbus is an open standard bus that allows devices of different manufacturers to integrate in one system. The devices and data can communicate by using standardized messages within the fieldbus protocol.

Fieldbus devices have microprocessor-based communications capabilities that allow process variables to carry a data quality signal, which can recognize errors faster. As a result, plant operators can get quick notification of abnormal conditions or the system can send out reminders for preventive maintenance. This can provide a more efficient plant and allow operations to make better decisions. One of the main aspects in the definition of fieldbus is interoperability. A user can replace one fieldbus device with a similar device with added functionality from a different supplier on the same fieldbus network while maintaining specified operations. Fieldbus reduces complexity of the project and provides the needed versatility in most projects. Also, fieldbus provides easy installation and reduces physical maintenance of the system, which provides cost benefits. Overall, there is quite a list of open protocols to choose from, including: CAN. Fieldbus Foundation, CEBus, WorldFIP. BitBus, ProfiBUS. Lonworks, BACNet, XlO, EIB, and CAB.

Division of control

As the control systems become more complex, with a large amount of variables, applications, and interlocks, it can become expensive, complex, and even cause unacceptable system performance. When the system becomes too unwieldy, one consideration would be to divide it into smaller parts the user can individually control. This method of partitioning the control becomes an attractive solution since it allows for simple development, and it is easier to maintain, operate, and administrate with a more predictable performance. The DCS, which has been in action since the 1970s, provides a data concentrator console connected to automation controllers that connect with remote I/O modules. These remote I/O modules connect to devices in the Meld and also connect to the controller with a proprietary communication network still in use today. With the concept of fieldbus in the market, the distributed control concept can work in conjunction with intelligent devices. These fieldbus devices with processing capability allow the devices in the fieldbus network to talk to one another, apply system control, and also transfer data to an operator human machine interface (HMI) console. By using these fieldbus devices, the control moves away from the controller and into the actual field devices, which is even more distributed.