- June 29, 2015
By Phil Couling, Schneider Electric
HMI and SCADA systems have been undergoing a series of quiet revolutions for many years now. With all their new, stronger and innovative capabilities, what is really needed to get the most out of next-gen HMI is next-gen thinking about how to apply them.
By Phil Couling, Director, Wonderware Software Product Marketing, Schneider Electric
This article was originally published in the 2015 Spring Edition of PULSE.
A lot more than hairstyles have changed since the ‘80s, when I first started working with SCADA and HMI systems. At that time there were no off-the-shelf SCADA or HMI software products; every project required a big, complex and expensive system based on a mini-computer, such as a DEC PDP or VAX; and each project typically involved modifications and code extensions taken from the last project. Additionally, requirements definition was an extensive, laborious and expensive undertaking, and the results dictated the functionality that would be hard-coded into the system, typically for life.
Most of the technology we take for granted and consider indispensable today wasn’t even being imagined by the majority of people 30 years ago. Smartphones, tablets, the Internet, multi-terabyte hard drives and even full-color flat screen monitors were barely dreams. Think about it: When Windows-based HMI (known as MMI at that time) became a reality in 1987 or so, after PC’s had entered the mainstream and Microsoft Windows had been launched, even a computer mouse was a pretty cool piece of technology! But now HMI has become so indispensable to so many industries that, much like it is tough to recall exactly how we got anything done before the internet, it is tough to recall how manufacturing and industrial companies operated effectively before PC-based HMI and SCADA systems.
While the entire universe of things we call technology is so radically different today than it was in 1987, we still use the exact same labels—HMI and SCADA—to refer to the core real-time systems that lie at the heart of so many industrial businesses. And that is a shame, mostly because those labels tend to imply there is some kind of equivalence between what is possible with today’s HMI technology and what was possible with the first generation of HMI technology. It’s also very unusual. Most products and technology are usually given or take on shiny new names as they evolve. For example, the telephone became a push-button phone, then a mobile phone, then a flip-phone and now a smartphone. And closer to home, we have CIM, MRP, MRP II and now ERP. Yet the products we continue to label HMI and SCADA today are as different from their predecessors as the hottest smartphone is from that old rotary phone. While we can still make local calls with a smartphone, and still draw graphics on a screen and associate them with physical I/O using today’s HMI products, if that’s all we are doing with them, we are really missing out.
While modern SCADA and HMI systems can still perform the same basic functions they performed in those early days, business demands, underlying technology and dramatically changing operator roles continue to influence the rapid evolution of these systems and deliver solutions for a range of contemporary business challenges.
Marketers often talk about “next generation” in the context of software systems, but HMI and SCADA systems have been undergoing a series of quiet revolutions for many years now. With all their new, stronger and innovative capabilities, what is really needed to get the most out of next-gen HMI is next-gen thinking about how to apply them.
Visualize the Process and the Business, not just the Equipment
The first part of next-gen thinking is to recognize that our operational focus has shifted from being equipment-based to role-based. Operations personnel are now responsible for ever-larger areas of the plant, if not even multiple plants. To enable their success, it is necessary to augment or, in some cases, replace the representation of physical equipment on an HMI screen, regardless of how elegant and sophisticated that might be, with HMI screens and applications that will help operators visualize logical portions or logical operations of the process. Logical portions might now be an entire production line, an entire facility or even a number of related plant locations across a wide area. A logical operation might be a screen or screens specifically designed to optimize process startup and/or shutdown. We refer to the latter as Goal-Oriented Design, where the HMI/SCADA screens are planned and implemented to support specific operational goals. This is very different from the majority of P&ID-derived HMI screens, which are equipment-centric and comprise elaborate depictions of pumps, vessels, valves and piping. When the principles of goal-oriented design within the HMI are closely matched to the goals of the business, the benefits can be very significant.
Comparisons of poor, better, and best practices in HMI design
Present Actionable Information, not Raw Data
Traditional approaches to HMI are closely associated with the physical inputs and outputs of the system under control, with graphical representations on an HMI screen. In the early days of HMI, instrumentation was very expensive, few I/O data points needed to be managed and it was quite logical to represent many of them as values directly on an HMI screen. HMI and SCADA systems represented simple I/O values in the form of “tags,” and the graphical animations and visualizations possible with the early HMI systems lent themselves very well to that kind of representation. The burden of understanding what each of those values meant and how to respond appropriately when those values changed fell upon the operator, and it frequently required years of experience to interpret that data properly.
Fast forward to today. Now there is an overwhelming volume of real-world data and I/O coming into the system. Continued representation of all of the physical data using those old-fashioned techniques would not only be an extraordinary engineering challenge, but would also be completely overwhelming for operations. The experience and expertise required to make sense of all the data would be extraordinarily high, and the cognitive burden on the individual would be extreme.
With next-gen thinking, modern HMI and SCADA systems represent information in the form of “objects,” which provide a more logical view of all that data. But not only that, next-gen HMI can add context for all that data, as well as make standardization and engineering more productive. Using objects to represent equipment in an automation system is not new, yet many HMI and SCADA implementations do not fully exploit the benefits offered by the object capabilities the systems have. Objects allow large collections of related I/O to be grouped together, along with the limits, alarming information, graphical representation and equipment connectivity information. When such information is organized and then presented in an appropriate, understandable fashion, not only can it dramatically reduce the cognitive burden for the operator, it can enable inexperienced operators to behave more like experienced operators.
Pursue Excellence through Situational Awareness
While the phrase “situational awareness” has been in the industry vocabulary for some time, most notably in refining and petrochemicals where safety is of utmost importance, it is now something that benefits most industries.
Examples of best practice HMI design applied to some real-world requirements, in this case water filtration
Situational awareness is not a feature of an HMI or SCADA system. It is a valuable benefit that operators and users derive from using specific best practices when they design their displays and user interfaces. These best practices were developed in safety-critical industries to ensure maximum operator effectiveness and to mitigate the risk of abnormal situations, which could result in a catastrophe. But now these proven principles are being applied to help maximize productivity and availability while minimizing costs, such as raw materials, energy consumption and waste, and they are generally applicable to a majority of industries. This is particularly important when we consider the quickly and ever-changing global economy, competitive landscape, material science, costs and sources of energy, and so much more.
While it has been technically possible to apply these principles in an HMI deployment for a long while, until recently the necessary expertise to do so has been scarce and expensive, and the architectures of most HMI systems did not allow software vendors to offer robust support for these principles within their products. The burden for developing HMI screens to these standards was left to the implementation teams. What’s more, a majority of HMI users, not being familiar with these techniques or recognizing how beneficial they could be, have not specified the inclusion of situational awareness in their HMI implementations. The most modern HMI and SCADA systems now provide deep support for these principles and directly embed best-practice principles into the product. This can dramatically change the design challenge: Instead of concerning themselves with the mechanics of building elaborate graphics, design teams can now focus on what decisions the operators should be making to optimize business value. Then they design the user interface from standard components to facilitate those decisions. With the right HMI software choice and next-gen thinking, implementing best-practice principles can be simple, efficient, cost-effective and very valuable.
Evolve from Perception to Projection to Improve Decision Making
Traditional approaches of showing simple numerical data or representation of a simple value, such as a level, pressure, temperature, flow, etc., only communicate simplistic information to the operator. This is simple perception: The operator can quickly determine what the value is, but not much else can be gleaned. How that simple information is actually processed will vary greatly depending on the experience of the operator. By adding contextual information regarding the expected value, as well as the current value, the HMI can assist the operator with comprehension of the information. At this point, the HMI is actually augmenting the operator’s experience. The operator is less dependent on his or her ability to remember lots of process-specific values.
The next opportunity is to have the system help determine if an action is required and indicate the consequences of either taking or not taking that action. This is called projection, where the system has removed much of that cognitive burden from the operator. The ultimate level of HMI and SCADA design, projection allows even inexperienced operators to quickly grasp the behavior of an unfamiliar system and to anticipate the consequences of their actions. Modern HMI and SCADA systems fully support this level of operation through goal-oriented design, effective window structure, effective color usage, actionable alarm management and effective design elements.
The Next Generation
Deep support for situational awareness and goal-oriented design in HMI/SCADA software is available today. The latest generation of HMIs don’t merely live on a single PC screen. They are now part of the infrastructure, providing critical, actionable information to key decision makers throughout the organization on a wide and increasing variety of devices: notebooks, tablets, smartphones and, recently, even smart watches. Contemporary HMI technology allows the integration of information from a multitude of sources: cameras, maintenance systems, Web services, inventory systems, planning systems and of course I/O from local or remote equipment. Today’s HMI/SCADA software already provides incredible capabilities to make users and operators far more productive, while dramatically reducing training times for new operators.
Of course the user isn’t the only stakeholder when it comes to these systems. Next-gen HMI/SCADA systems make it easy for engineers and system builders to implement, deliver and maintain these sophisticated features safely, efficiently and within standards compliance. Next-gen systems also help engineering teams maximize reuse of existing engineering work, with the ability to scale and support the implementation remotely.
At the end of the day, next-gen HMI is really the one you implement next. Compared to what many companies are actually using now, next-gen HMI and SCADA is already here, and the pace of evolution continues to accelerate. Ultimately, next-gen HMI/SCADA is simply next-gen thinking: looking anew at how to use these products, the problems a new approach might solve and the opportunities for improvement you might uncover when you think outside the box. Chances are the software that can help you realize your goals already exists.
About the Author
Phil Couling has over 30 years experience of working with computers, software and technology in industry. From designing industrial software systems, to writing code for them, advising on strategic uses of them and evangelizing them, Phil has worked as an engineer, consultant and marketer for some of the most influential companies in industrial automation and control: Siemens, Logica, Westinghouse, Honeywell and Microsoft. Since 2006, he has lead Global Marketing for Wonderware Supervisory HMI software as part of Invensys and now Schneider Electric.
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