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The aim of this paper is to provide an update on the status of current fieldbuses and high‐speed Ethernet technologies for industrial automation.

The paper provides information on the various fieldbus technologies for industrial automation connectivity and examines high‐speed deterministic Ethernets for automated manufacturing and assembly plant.

The paper finds that the standards issue has still not been fully resolved, that Ethernets reduce manufacturing costs compared with conventional fieldbuses, that most effort has gone into making Ethernets work deterministically, rather than concentrating on IT and enterprise resource planning (ERP) integration, and that the internet will increasingly feed real‐time data to ERP levels.

The paper provides information on recent developments in Ethernet technologies.

The purpose of this paper is to describe how emerging open standards are replacing traditional industrial networks. Current industrial Ethernet networks are not interoperable; thus, limiting the potential capabilities for the Industrial Internet of Things (IIoT). There is no forthcoming new generation fieldbus standard to integrate into the IIoT and Industry 4.0 revolution. The open platform communications unified architecture (OPC UA) time-sensitive networking (TSN) is a potential vendor-independent successor technology for the factory network. The OPC UA is a data exchange standard for industrial communication, and TSN is an Institute of Electrical and Electronics Engineers standard for Ethernet that supports real-time behaviour. The merging of these open standard solutions can facilitate cross-vendor interoperability for Industry 4.0 and IIoT products.

A brief review of the history of the fieldbus standards is presented, which highlights the shortcomings for current industrial systems in meeting converged traffic solutions. An experimental system for the OPC UA TSN is described to demonstrate an approach to developing a three-layer factory network system with an emphasis on the field layer.

From the multitude of existing industrial network schemes, there is a convergence pathway in solutions based on TSN Ethernet and OPC UA. At the field level, basic timing measurements in this paper show that the OPC UA TSN can meet the basic critical timing requirements for a fieldbus network.

This paper uniquely focuses on the specific fieldbus standards elements of industrial networks evolution and traces the developments from the early history to the current developing integration in IIoT context.

Discusses the distribution of application functions to process‐oriented field devices and process‐remote components in distributed automation systems. Describes the use of fieldbus systems, function block technology based on standardised function blocks and a suitable infrastructure to enable these function blocks to cooperate during run time.

To emphasise the need for remote fieldbus diagnostics and to show a technical solution based on industry standard approaches.

The design and approach takes a Profibus fieldbus, as an example candidate, and captures the diagnostic data using an OPC model and then uses a Java RMI object broker to develop/support the remote end clients.

The findings show, by an implementation example, that it is possible to implement remote diagnostics for a fieldbus network, without interfering with the operation of the network. The findings also highlight the need for security in such a solution.

The implementation example is rather cumbersome, but the paper suggests that all the hardware and software could be implemented on a single embedded processor in a single box. The security issues are flagged as a possible limitation, but solution approaches are briefly suggested.

The paper highlights the lack of standardisation around fieldbus diagnostics. Even for the same fieldbus type, different manufacturers will use different diagnostic protocols and codes. This paper suggests a practical implementation, where the diagnostic codes can be interpreted a fixed stage and presented to an end client in a consistent manner.

This work is based on a two year original research project. The solution makes heavy use of industry standard protocols but the work is original.

One of the main benefits of the fieldbus technology is its significant reduction in wiring. This is because each process requires only one wire to be run to the main cable. Installation costs are further reduced because the fieldbus is a multi‐drop rather than a point‐to‐point system. (The multi‐drop network can offer a 5:1 reduction in field wiring expense.) A number of pneumatics manufacturers have already developed devices for various programmable logic controller (PLC) fieldbus protocols, in the form of control blocks mounted directly on to standard pneumatic valve manifolds. The next generation of modular valve manifolds has emerged too. These do not need wiring, because they are based on a virtually “plug‐and‐play” design and installation method. This means that with this modular design one simply selects the valve configuration needed for the process, plugs the modules together, and the manifold is ready to connect into a fieldbus network.

Almost all industrial systems are distributed with multiple control points which interact to a limited extent, for which the idea of distribution of task at local (field) level is emerging. As locally‐based application tasks can reduce control delays, a fieldbus‐based smart and reliable DCS solution is recognised as a leader for real‐time industrial automation. Advanced control system has turned itself towards the implementation of digital distributed control systems (DCS) from centralised control systems. The phenomenon is becoming very popular because of its advantages over the whole operating system. Presents a case study for realising manufacturing systems (production lines) with fieldbus technology. The local operating network (LON) fieldbus system was chosen for this purpose because of availability of a wide range of products. Emphasises the reliability aspects of the control systems. A representative of a conveyor system, integrated with field devices, was conceived as the target platform.

Ethernet continues to evolve as a viable fieldbus technology for industrial automation. This paper seeks to discuss the development of the Common Industrial Protocol (CIP) for Ethernet and standards with particular reference to time synchronisation, real time motion control and safety.

The CIP is introduced, with an overview of four network adaptations: CompoNet, DeviceNet, ControlNet, and EtherNet/IP. Developments in the EtherNet/IP implementation are discussed, along with key features. These include CIP Safety to meet the requirements for safety‐related control, CIP Sync for time synchronisation across CIP networks and CIP motion for real‐time closed loop motion control.

Standard, unmodified Ethernet will support time synchronisation, real time motion control and safety‐related applications with the CIP adaptation EtherNet/IP. The CIP enables complete integration of control with information, multiple CIP networks and internet technologies. CIP provides seamless communication from the plant floor throughout the enterprise, with a scalable and coherent architecture, incorporating functionality, such as safety, time synchronisation and motion control, hitherto only available with specialised or incompatible networks.

The implementations of CIP Sync, CIP Motion and CIP Safety and the corresponding standards provide functionality and flexibility not available from disparate specialist networks. The ability to fully integrate internet technologies and safety, synchronisation, motion and safety together is a distinguishing feature. Industrial Ethernet technologies vary in the ability to integrate to the same level of functionality and offer similar flexibility.

The development of CIP technology and the use of open standards are described. The opportunity to use the combination of an established automation protocol and standard, unmodified Ethernet provides potential cost benefits, flexibility, and innovative solutions, whilst providing integration, performance and cost advantages.