Optimizing your HMI
Taking time to reevaluate workstations and interfaces can uncover countless ways to increase performance, optimize efficiency, and boost profitability.
Are you maximizing the power of your facility’s HMIs and operator interfaces? In all honesty, probably not. Like our brains and our PCs, such equipment rarely is used to the full extent of its ability. Too often, system capacity lies dormant, untapped, and unused—a situation few can afford in an uncertain and changing economy.
According to Chris Stearns, Honeywell product manager, in most cases when a plant installs an automation system, it builds what it needs to meet present circumstances, and then uses about 20% of its capability. “Maybe parts of the system aren’t appropriate for what is being done at the moment or maybe there aren’t sufficient—or sufficiently trained—personnel available to do any more,” he said. “Regardless of the reason, there is still a lot of functionality there that’s not being used or used as efficiently as it could be.”
Admittedly, it is a challenge to maximize the potential of any system. With a little bit of effort and investment, however, many plants can coax more efficiency and productivity out of their HMIs and interfaces, and enable managers and operators alike to do their jobs better. Control Engineering recently asked Stearns and several other experts in this area to share some thoughts and offer some suggestions for boosting performance of these devices. Here is a look at some of their ideas and recommendations.
Efficiency equals flexibility, reusability
Every plant situation is different, of course, admitted Stearns, but in most cases more can usually be done than may be apparent on the surface. “With a DCS, an alarm summary is a given,” he said. “So many facilities don’t consider that they might be able to handle alarms in a different or better way. The operator has an alarm summary screen and merely goes about dealing with alarms as they happen. But a lot of functionality inherent in the system is not being used. Alarm summaries offer more than a list; they can be sorted, organized, and filtered based on plant need. In that way, a more efficient operation can be achieved.”
In the opinion of Keith McPherson, director of market development, visualization, and information software, Rockwell Automation, reusability is a major key to achieving HMI system design productivity and efficiency. “Products need to be designed to work together to yield reusable objects,” he said. “Then, when the HMI is installed, building blocks are already in place and templates already exist to help create the reporting and analytical tools used at other levels of plant operations. All systems involve several pieces. Traditionally, those pieces are designed multiple times, which is very inefficient and leads to disjointed systems looking at the same data. Systems should be configured so that they put data into proper context.”
The data an operator needs to run a work cell or control a process isn’t the same data the line manager needs to do his job, McPherson explained. “Or even if it is the same, it likely needs to be presented in a different fashion,” he said. “Starting from scratch for each application or function wastes time and productivity. If the foundation for the system is laid in the control layer or SCADA layer, and then built upon, a lot can be accomplished quickly and easily without a lot of reconfiguration and reintegration.” Plants need to leverage what they have through better use of reporting and data management tools, said McPherson, adding that information-centric tools that access the right data can enable better decisions. “It doesn’t require a new infrastructure to do that,” he went on. “It’s a matter of connecting to the real-time data in the controllers and the HMIs, of getting historical data from the historians, maintenance management systems, or production schedulers. And only since the recent economic downturn have plants started actively looking for ways to do these analyses.”
Scott Miller, Rockwell Automation business manager, visualization software, supports McPherson’s view. “Investing in and developing a control strategy that is reusable and flexible and will pay dividends as the plant’s information needs evolve,” he said. “All plant systems and operations are dynamic. What a plant needs today is not what it needed three months ago or will need three months from now to operate optimally. Building rich capability in your control, visualization, and information systems is a way to build for the future.”
More than eye candy
Although hardware developments typically occur at a slower rate than software, they impact efficiency as well. Displays are evolving, getting better and brighter. Graphics rendering technology is improving, providing tangible benefits that go beyond building attractive screens. “Plants need to look at leveraging better rendering technologies to make their system’s graphics clearer and more intuitive,” noted Miller. “Those seeking to maximize display efficiency also can do so through mobility and remote data access. Mobile devices save keystrokes and eliminate operator error,” he added. “The need for flexibility will drive the adoption and acceptance of more and more wireless components.”
And, fortunately, operators entering the workforce today are just what the workplace ordered when it comes to embracing and applying these advanced technologies. “Workforce demographics indicate that a lot of operators in North America will be retiring in the next decade or less,” said Miller. “Their replacements will be people who have grown up with sophisticated hardware and software, with Twitter and iPhones. They will have a different perspective on information than did previous generations. That factor is driving current research and development, and will drive HMI systems of the future. As the need grows for richer graphics and greater integration capabilities to support modern mobile platforms, we will have operators who know how to and want to use them.”
McPherson agrees. “Once operators were tied to a terminal, but that is changing. Operators today are more mobile that they were five years ago, and that fact alone makes them more efficient. They move around using portable devices. They use Web-based browsers routinely. They are more comfortable with new technology and sophisticated graphics. If they can access better information, they can react quicker and do their jobs more effectively. But that can only happen if they receive data in the correct form, at the right time, in the right context. And the need for that is more important today than it was five years ago.”
Manufacturers today need to get all they can out of what they have, added Alan Cone, product manager at Siemens Industry, concurring that advancing display technology is impacting efficiency—and sustainability. “Companies today are moving toward a wide-screen format,” he said. “It gives an operator more screen size to view—and more importantly more information—in the same physical device size. Greater screen resolution is available, and when faced with an equipment change-out, many plants now are adopting LED technology that offers brighter screens overall and the flexibility to dim them at will. Although their lifespan is no longer than traditional HMIs (40,000 to 50,000 hours), LEDs use less energy, making them a ‘greener’ choice.”
All about the operator
One aspect of HMI/OI efficiency often overlooked is the human factor. “Whether you’re using a vintage CRT or a modern wide-screen flat panel,” said Honeywell’s Stearns, “it’s really all about what you put in front of the operator: What you display, how, and when are really key to an effective and efficient response. Quality operator training can reap major performance gains. An operator who can get better information or the right information at the right time can do a better job.”
Training is a huge issue, stressed Stearns. “Operators can’t be as effective as they could be without continual training,” he said. “In recent years, plants have begun to recognize that. Even the same workers using the same interfaces can operate more efficiently if they receive refresher training a couple of times a year to make sure they know what they’re doing and that they’re doing their jobs in the best way possible. Thankfully, abnormal situations don’t occur often. But training exercises are a way to stay current, to ensure that operators will respond properly when that group of alarms that means something comes in. Training simulators keep operators ready to respond. An investment in training makes the HMI more effective.”
Training employees to do more at the terminal is both a benefit to and result of today’s global marketplace, observed Siemens’ product manager Wayne Patterson. “In particular, OEMs that have a global presence focus on how to support machines more efficiently,” he said. “They don’t want to send employees around the world to maintain a line. It’s too expensive. Putting instruction manuals right on the HMI, through remote terminal connections, lets properly trained operators do more, saving time and money and getting the job done.”
When all is said and done
No matter how or how well they are used, HMIs and OIs will always have a strong presence in manufacturing. “People really need them,” emphasized Cone, “and will become increasingly dependent on them. Facilities want to put more and more information on their screens, and tools are continuing to evolve that let them do that. Even the use of smart phones may increase at the supervisory level…and maybe at the maintenance level, although not for production. But mobile devices will likely proliferate.”
The days of maintenance and instrument technicians having only a toolbox are going away as more and more tasks become electronic. “The way employees interact and collaborate is changing,” said Stearns, picking up on Patterson’s earlier comments on our global environment. “For example, a technician with a mobile device is investigating a problem with an asset. He gathers the necessary data electronically with pictures, videos, and other measured data using his mobile device. He then sends it through a central system to a product expert in Switzerland. The expert views the recording online and tells the technician how to fix the device. What might take days or weeks a few years ago, now happens almost instantly. Technology has dissolved geographical barriers.”
Stearns cautions, however, against letting technology become a solution looking for a problem. “Technology is an enabler, not an end-all,” he said. It’s not important unless it helps do what needs to be done. We need to solve problems, not just apply technology. Bells and whistles are fine in the commercial market, but in industry it’s more about safety, production, reliability, and efficiency.”
An HMI is basically a black box. Its value lies in what is done with it to help the operator do his job safely and efficiently. Manufacturers should not overlook the possibility that new products may be able to unlock greater capability within the same system. Tapping in to what can be done to keep existing systems optimal keeps operations dynamic in the most economical way.
Jeanine Katzel is a contributing editor to Control Engineering. Reach her at jkatzel(at)sbcglobal.net.
Going green, saving energy
A facility at the point of changing out HMIs or OIs might want to consider “going green” by choosing energy-saving components when possible. One option is Siemens’ ProfiEnergy energy management system, which helps facilities incorporate dynamic energy management into their HMIs.
The technology, explained Alan Cone, product manager at Siemens Industry, lets operators easily shut down loads that are not required during nonproductive periods. Existing hardware and software can be integrated simply using ProfiEnergy power modules such as the Simatic ET 200S PM-E RO power module (shown) or function blocks in the controller.
“You can add function blocks at the PLC to control equipment,” said Cone. “If the production unit takes a half-hour lunch break, an instruction code can be programmed into the system to shut down unused equipment for that time so it is not using energy unnecessarily. It has the capability within the HMI to be programmed so that it ramps back up 5 minutes before personnel return. It is extremely flexible.”
More information about ProfiEnergy is available in an online brochure.
Portable panels promote efficiency
Mobile panels are expected to proliferate because they give operators the ability to be more flexible and efficient (above). Mobile devices also save keystrokes and reduce operator error. These devices will take another step forward later this year when Siemens Industry begins marketing a wireless mobile panel (inset) in the U.S. (The device is already marketed in Europe.) Similar to other Siemens mobile panels, Simatic Mobile Panel 277 is wireless, so no physical cable connects it to the PLC process. The unit features an 8-in. color touchscreen, can be easily carried around the plant, and will feature built-in E-stop safety functionality.