Speed matters, especially when building modern production machinery to offer the highest levels of productivity, so it is no surprise to see gigabit Ethernet speeds in industrial networks. John Browett of CLPA looks at where these networks are currently being used, and speculates on how they will become the norm in many applications.
The pressures on manufacturers continue to build, with global competition now a fact of life in virtually every industry, driving a need to reduce manufacturing costs and increase productivity. Part of the picture in addressing these requirements is the increased performance of devices such as servo drives, inverters, motion controllers, PLCs and more. But networks, too, are playing an increasingly important role.
Open automation networks first emerged in the 1990s as serial based fieldbus systems. These provided a simple means of passing information between controllers and field devices, eliminating the need for complex reams of hard-wired cables. An enabler – perhaps, the critical enabler – for a new breed of intelligent machines and systems, the various open fieldbus options heralded a new era of distributed control. They reduced the cost and complexity of machinery while increasing performance and reliability and hence shortened time to market and increased uptime.
Industry enjoyed these benefits for a number of years, but soon a new technology came knocking at the door. Ethernet was already well established in the IT world and was slowly beginning to creep into the automation domain. These first steps were not so successful, as Ethernet had not been designed with the demands of the shop floor in mind. Hence the initial systems lacked the necessary levels of determinism for reliable industrial control and sufficiently rugged hardware was difficult to find.
One of the key drivers for Ethernet was the promise of being able to seamlessly link the plant floor with the higher-level enterprise. This would enable production logistics to be tied to demand, whilst providing the control data to the higher level systems that would allow better production decisions to be made. This led to new pressures to provide additional productivity gains.
Once these initial pressures were addressed, the industry began to see how Ethernet could offer other benefits further down the hierarchy by linking controllers to controllers and field devices to controllers. Soon the determinism issues were solved and industrial grade hardware became commonplace. Industrial Ethernet has now spread rapidly throughout automation and while fieldbuses will remain for years to come, the attention is now on further development of Ethernet-based technologies.
Seamless data transfer
Industrial Ethernet now provides a variety of open networking standards that have the potential to provide seamless transfers of data through all layers of the enterprise. Systems have emerged for conventional control, safety, motion and energy management, enabling unprecedented levels of productivity, flexibility and performance.
CC-Link, the open network technology managed by CLPA (CC-Link Partner Association) has itself evolved in line with developing productivity requirements. CC-Link is a globally accepted open network, with over 9,000,000 installed devices worldwide. Over 1200 different products are available from 260 manufacturers, meeting the needs of every sector of industry and every imaginable application.
While CC Link began as an open fieldbus, the CLPA was quick to see the move towards industrial Ethernet and introduced CC Link IE (Industrial Ethernet) in 2007. This has undergone several refinements in subsequent years and today it is the only open industrial Ethernet that can run conventional, safety, energy management and motion control all on the same cable, offering significant installation and maintenance benefits. This is noteworthy on its own and – significantly – CC Link IE is also the only open Ethernet-based network available that does all this at gigabit speeds.
Why is this important? Much of the debate about industrial Ethernet technologies has focused on the need for seamless data transfer between the plant floor, the control layers and the higher-level enterprise. Undoubtedly this is important, but so too is a recognition of the different network performance requirements at these different levels of activity. At the highest levels of the enterprise, the focus is very much on data capacity, whilst at critical points on the plant floor the emphasis is very much on real-time performance.
Key machine operations depend on high-speed data communications between distributed I/O and on real-time motion control information. At the same time, the need to monitor and optimise energy usage has driven a requirement to collect energy data in real time from huge numbers of intelligent devices and to be able to act on that data to reduce the cost of energy involved in production.
CC-Link IE is the industrial Ethernet version of CC-Link and provides a transparent, open network hierarchy with speeds of 1Gbit/s –the highest speed currently available from any industrial Ethernet standard. Integrating device, motion, safety and energy management functions on a single cable, CC-Link IE helps to deliver high levels of productivity in plant and machinery.
Thus CC-Link IE meets the speed and bandwidth requirements of the most demanding industrial automation applications, including packaging machines, semiconductor production, automotive production, liquid crystal production and more. The productivity benefits to be gained are significant; suddenly, controller-side limitations are lifted and the only constraints remaining are mechanical and organisational.
Looking to the future, it is inevitable that the pressures on manufacturers across all industries will continue to increase, driving new benchmark standards for production line performance, making high-speed networking and real-time control capability even more important. At the same time, increasing energy costs will drive a requirement to monitor energy consumption right down to the individual device, with a corresponding need to provide real-time energy management reports. The ability to combine production control information with energy information will enable the simultaneous cross-optimisation of operational control and energy management across new swathes of applications.
We can see, then, that gigabit speed industrial Ethernet can be a crucial technology in enabling manufacturers to meet the production demands of today and the challenges of tomorrow. CC-Link IE is well placed to help companies address these needs, fulfilling its promise to be a single, high-performance, open Ethernet technology offering all the features required by even the most demanding applications.
To learn more about CC-Link please go to www.the-non-stop-open-network.com.