The Ethernet evolution in industry

In our day-to-day office and personal environments, we’ve become accustomed to a wealth of benefits delivered by internet-based technologies. As we move further and further towards a common IP highway, we consider the significant benefits that could be delivered by Ethernet backbones in industrial processes.

Will Ethernet bridge the divide between business and production environments or are we already there?

The simple answer to the above question is that Ethernet technology has evolved to meet the needs of the industrial automation market and its capabilities provide significant advantages compared to the older proprietary networks. Some of these advantages include:

• High-speed communications, 10 Mbit, 100 Mbit and 1 Gbit options.
• Large data packet size coupled with higher speeds improves communications to large I/O drops and intelligent field devices.
• More predictable communications with the introduction of Ethernet I/O scanning in automation systems.
• No need to specially train personnel on proprietary networks as Ethernet is taught in universities and understood by personnel in other industries.
• Simplified configuration and troubleshooting allows management of the entire network from one central location and access to a wide range of existing Ethernet diagnostic tools.

Yet despite such advantages, some organisations continue to express concerns regarding the use of Ethernet at the plant level. These concerns have chiefly focused on nervousness regarding its real-time capabilities and the robustness needed to operate in the harsh environment of a plant floor. While some of these concerns may have been valid previously, developments in Ethernet technology mean they should no longer be an issue. Today’s Ethernet solutions directly address the previous limitations expressed by end users.

Ethernet development to suit industrial processes

In the 1990s, vendors recognised that the inherent advantages of Ethernet would make it an attractive fieldbus network and began to build open application protocols based on Ethernet. The protocols used Layers 1 and 2 of the Ethernet stack and a new application layer optimised for automation applications.

The resulting protocols needed to have the flexibility to meet a range of industrial requirements while being easy to use for non-IT personnel within the plant. An additional requirement was for these open protocols to use standard Ethernet hardware technology so users could utilise common off-the-shelf network components. Now large device catalogues allow customers to pick best-in-class devices for their system, and be assured that these devices will work together.

The move to Ethernet-enabled PACs

With many businesses currently focusing on maximising output from existing installations, one key means of achieving this improved performance and overcoming some of their challenges is by making better use of the vast amounts of information which exist within their operations.

The move towards the connected enterprise requires a technology architecture that is capable of moving large volumes of data and information from the many connected devices found across the operation. This data is moved to the higher level applications and systems used for visualisation and analysis. At the centre of this technology architecture is the programmable automation controller (PAC). The traditional role of the PAC and its predecessor, the PLC, has been to monitor and control the devices, equipment, applications and processes found within the industrial operation.

The new generation of PAC implements functions and services which support:

• secure and efficient process automation
• Ethernet transparency, distributed intelligence
• links with business applications
• web integration
• interoperability
• device communication using Ethernet and web standards

The new generation PAC with Ethernet at its core not only ensures that its performance exceeds the demands placed on it, both now and in the future, but that it achieves this while maintaining high levels of security. Cybersecurity threats from external or internal sources are issues confronting all manufacturing companies today, and deliberate or accidental breaches to system integrity have the potential to impact not only profits but also people and the environment.

PACs, big data analysis and energy management

With a global focus on sustainability, we now find energy measurement information available from a large number of sources. Power meters, smart devices and process instruments are the most common ones. All of these sources of information need to be brought together and combined with process data in order to achieve effective energy management. The highest quality of this data is obtained from smart devices and instrumentation, so the control system needs to provide open interfaces to each of these different devices and have the ability to time stamp (to milliseconds) the data which they are collecting (both electrical and process data). The combination of high-quality process and energy information shifts the data value from energy dashboard variables to being an information source which can indicate faults within the process that cannot otherwise be detected.

Current levels of energy management are mostly focused on energy consumption and looking at peak demand or power factor. These measures are the ones which need to be used in order to have the most direct impact on the processes to control our energy consumption. Beyond this, there is more analysis which can be based on energy data that provides predictive rather than reactive information about the process. To complete this analysis there needs to be increased access to more information that is available within the smarter drives and power meters that are available today.

The information available in smart devices and meters is growing, but they are typically located on proprietary networks or on open networks dedicated for PAC controls. These networks ensure that appropriate priority is given to the control messages that enable great process automation. But they force engineers to select a subset of the data which is required for energy management and copy it into the PACs in order to transfer a set of data to energy management and other systems. This replicated data is limited in its scope because of the need for the PAC, rather than acting as a mailbox.

To unlock all this automation and energy management data for big data analysis, without compromising the control focus required, there needs to be open access from remote systems to this wealth of data. Any transfer solution places unnecessary load on the controller or reduces the data available. The best solution is to allow direct Ethernet connection between analysis applications and the smart devices.

To obtain the various multidisciplinary functionalities needed to run a plant, process end users in industries such as water and wastewater, food and beverage, hydropower, metals and mining, as well as in the cement and glass industries, require secure, reliable interoperability among their automation products. As a hub for both real-time control and information, PACs can benefit from being designed with an open Ethernet backbone to optimise connectivity and communications, increase bandwidth and provide a high level of security.

PACs typically provide complete automation, real-time information and motion control functionality using a single programming and engineering tool and a single programming language. PACs also provide transparent access across all parameters and functions, along with easy integration to the enterprise though the use of internet and other IT standards.

As the needs of process end users continue to evolve to meet their ever-increasing challenges for productivity, flexibility, efficiency and profitability, the designs of PACs have also evolved. PACs must leverage the latest and most powerful silicon offerings in hardware to increase robustness and the reliability of the memory. PACs must also provide a high memory capacity to avoid creating bottlenecks.

Evolution from the PAC to the ePAC

With today’s process plants requiring more rapid changeover capabilities, it is critical to be able to change automation configurations and architectures on the fly, without stopping the process. PACs must also have an architecture geared for maximising production flexibility, data and information transparency, and openness for diagnostics performed both locally and remotely. This has led to the next evolution of the PAC, known as the ePAC.

Harnessing the best parts of Ethernet and PAC technologies, the ePAC offers users an even more adaptable platform to integrate with their existing hardware. Companies no longer have to take a costly rip-and-replace approach to deploying new solutions and now have an easier way of migrating operations to the platform. The end result allows companies to pick and choose the right services for them from multiple vendors, instead of relying on a one-size-fits-all approach.

ARC has observed a major trend for process end users to employ open networking technologies, such as EtherNet/IP, and to be able to take advantage of an open integration environment, higher information bandwidth, standardisation, cost savings, the flexibility to physically move portions of their processing and increased data visibility at all levels. The increasing need for distributed intelligence makes networking critically important. This market driver is leading to increased adoption of ePACs with built-in Ethernet backbones, especially for connectivity to either on-premise or cloud-based enterprise applications, such as enterprise resource planning (ERP), manufacturing execution systems (MES), enterprise asset management (EAM) and supply chain management (SCM).

Today’s connected applications demand tighter integration and more information, with a higher expectation that the control system will initiate communication, update the controller at the device level in real time and serve up potentially massive quantities of information. Automation platforms with a built-in Ethernet backbone help meet these requirements in a highly flexible manner because they can support instant access, regardless of hierarchy, and avoid the limitations of proprietary software interfaces and protocols.

Network-centric ePACs with a built-in Ethernet backbone are accelerating the trend towards distributed I/O, providing process end users with significant cabling cost savings and reductions in installation, start-up and commissioning costs. Using Ethernet cables to replace I/O extension cables and fieldbus cables can result in significant cabling cost savings. Ethernet cables are also much less expensive than even standard coaxial cables. In addition, the use of single optical fibres to connect long-distance remote drops and devices can also result in significant cabling cost savings. ePACs create new opportunities for both traditional in-rack applications as well as for distributed I/O.

At the control level, process end users seek an increasingly more flexible, expandable, interchangeable and reliable control platform that ideally covers the widest range of required applications. They’re looking for the ability to easily interface their control platforms with both fixed/wired and mobile/wireless HMIs, serial devices, motors, thermocouples, analog and digital I/Os, and other equipment and devices. With control room and rack space at a premium, they want automation platforms with the smallest practical footprint. And since power consumption affects both electricity and air-conditioning costs, they’re looking for more energy-efficient solutions.

Taking the journey

System modernisation issues are becoming more important than ever as industries increasingly move to automate and analyse big data. Several years ago, ARC estimated that worldwide, installed process automation systems worth about $65 billion are reaching the end of their useful life, with most over 20 years of age.

When evaluating automation system modernisation projects, end users should seek solutions that minimise downtime and risk, while providing a tangible business value proposition that will have a real economic impact on their business. In many instances, ePACs will represent a viable, easily cost-justifiable modernisation solution.

ARC recommends process end users follow a stepwise approach that allows them to evolve the components of their legacy systems that have the greatest impact on their processing operations, while preserving the components that have not yet outlived their useful life. Process end users require an approach that leverages automated tools and a range of services targeted at reducing or even eliminating the downtime required to complete a modernisation project. When modernising from PAC to ePAC, end users should consider the benefits of selecting an ePAC that embeds all legacy technology in its microprocessor to help ensure compliance with older technology.