We are today at an interesting threshold in the evolution of networking technology: The emergence of Ethernet from the primordial networking jungle as the dominant technology has allowed thinking to evolve. Pragmatic networking issues now take second place to addressing how to utilise information effectively to drive sustainability in the modern enterprise.
As I embarked on the first few steps of my career in the automation Industry in 1986 little did I realise that I was already witnessing the humble beginnings of a networking revolution. Proprietary automation networks such as Data Highway were entering the market place, providing new possibilities in distributed control and visualisation for the automation user. Very quickly, pressure built for compatibility between competitive proprietary networks and so the drive for open standards was born.
The early nineties saw the emergence of open standards such as DeviceNet, Profibus, ControlNet and Foundation Fieldbus offering unparalleled levels of connectivity and interoperability. Simple products, such as motor overloads, became intelligent devices able to share information, opening up the possibility for predictive diagnostics and hence productivity gains. At the same time, Ethernet was becoming adopted as a high level network for interfacing the factory floor to the wider enterprise and increasingly for data acquisition applications. The networking revolution was well underway.
In the present decade, Ethernet has become more prevalent in industrial applications, including control, safety, motion, diagnostics and configuration. Information empowered decision making made possible by the Ethernet revolution is one reason why industrial customers expect to be investing so heavily in Ethernet. But what role does Ethernet networking play in sustainability today, and what of the future ?
We define sustainable production as cleaner, safer and more energy efficient. Production is cleaner when it reduces waste, eliminates emissions and consumes fewer natural resources. Production is safer when it protects workers, processes and equipment along with product integrity and quality. Sustainable production is more energy efficient when companies produce more goods with less energy. While regulatory compliance may have been the motivator in the past, today's resource shortages and economic demands require the elements within sustainable production to be addressed to ensure that organisations can remain competitive in the global economy.
Ethernet networking and safety
The replacement of electromechanical safety relays and hardwired interlocks with safety networks and controllers can drive down cost, increase maintainability and improve information flow, all of which contribute to sustainability. But the technology employed has to be appropriate for the application. One approach is to move away from the concept of safety networks in favour of structured safety architectures increasingly based on Ethernet.
Most simple applications don't need a full-blown safety PLC to manage the control loop. In this situation, all that is required from the safety network is support for peer-to-peer communications between simple devices - in effect, replacing a simple hardwired connection with a networked one.
Ethernet networking and energy efficiency
Visibility of energy consumption is a critical first step in implementing a sustainable energy strategy. Extending the Ethernet architecture to include network based power monitoring devices provides that enhanced visibility and facilitates energy optimisation. This approach can be adopted for key resources such as electricity, gas, steam and water within the facility. At the end of the day if you don't measure it, you can't manage it!
Adopting the right network architecture allows the enterprise to acquire data in a form that allows decisions to be taken based on forward prediction. Where before, managers had to monitor carefully and make a decision when they wanted to do something, now they simply set those parameters ahead of time and do the predictable things that save costs.
Lean manufacturing
The real value of networking is realised when information is used to improve visibility of production performance, to better track what happened or will happen, when and why, and ultimately to improve the utilisation of assets and thus return on investment. This is true in the example of energy usage but also in production and process disciplines too.
At the same time, the commercial world has been making significant cost savings by exploiting the power of Ethernet to converge their business systems on a common backbone. Where they once had a network for e-mail, a network for file servers, a network for the telephones and a network for security cameras, they now have a single information network that delivers all of their information needs. The challenge now is to extend that philosophy into the manufacturing space. Collaborations between automation suppliers and IT focused organisations, such as the recently announced Rockwell Automation/Cisco partnership, are enabling customers to realise the commercial benefits of a converged, enterprise-wide network.
Whither future technology?
Wireless networking - an emergent technology in automation - certainly provides flexibility and achieves long-term cost benefits. There are many providers of viable wireless systems, but the industry faces challenges - particularly marketplace acceptance - that currently hinder the widespread take-up of wireless networks for I/O, control and safety applications. Nevertheless, today's wireless technology is enabling an increasing number of other factory floor activities to become 'unplugged'. Programming, network and device configuration are good examples where wireless connectivity is proving a popular alternative.
Rockwell Automation believes wireless Ethernet will emerge as the standard for factory floor wireless connectivity. Just as the wider commercial needs of business has driven the capabilities of wired Ethernet up and prices down, demands such as wireless IP telephony will likewise drive wireless Ethernet to the point where it becomes a practical medium for demanding industrial control applications.
Is the network revolution complete? No - far from it; the next thirty years promises to be just as exciting as the last three decades.
Mark Daniels is drives marketing manager, Rockwell Automation