The first automobiles—ruggedly constructed to move people and cargo—bear little resemblance to the high-performance cars of today. Materials and technology improved, needs changed and what users wanted expanded to require designs that Henry Ford and his contemporaries never dreamed of. And so it is with SCADA systems.
From the perspective of a machine operator, a supervisory control and data acquisition (SCADA) system is the interface screens that show what’s happening deep in the plant or along the production line. But that hardware and software are just the front end of a vast network of connections that bring machine and process information to the eyes of people tasked with controlling them.
No longer confined to islands of automation, today’s SCADA systems extend like a web throughout an entire plant and—thanks to the Internet—to any place in the world. The size and complexity of SCADA systems has grown significantly in recent years alongside improvements to other automation systems, leading to the potential for expanded capabilities and business benefits. Getting those capabilities, however, often requires not only an upgrade, but also a rethinking of what your company needs its SCADA system to do.
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“The industrial Internet of Things (IoT) will focus on making machines more autonomous, increasing efficiency and productivity by reducing or even eliminating the need for human supervision,” says Bill Conley, M2M systems development engineering manager at B&B Electronics. “Wireless is one example of how evolving technology is allowing companies to expand the reach of their SCADA systems to monitor remote equipment for preventive maintenance, reducing downtime and costs.”
John Krajewski, director of product management, HMI/supervisory for Invensys, which is now part of Schneider Electric, says, “Trends are for larger systems, greater volumes of data, increased levels of automation, staffing proficiency issues and expanded use of remote operations.”
Older SCADA systems were never designed to connect with the number of machines, sensors and other assets that manufacturers now want to monitor and control. Nor were they designed to handle the amount of data traffic and records these connections can generate. This lack of scalability, including the ability to access information through the Internet, can be a significant barrier to improving the quality and productivity of manufacturing processes.
And just like everything else in the world of computers, human machine interface (HMI) hardware and software lifespans are not as long as those of traditional industrial products like programmable controllers. The widely deployed Windows XP platform, which Microsoft is no longer supporting with service patches or security updates after April, is just one example of why SCADA systems need periodic refreshing.
“Basic or machine-level HMI tends to have longer lifespans, 10-15 years,” Krajewski adds, ”but hardware or operating systems for central control rooms become obsolete on average every seven to 10 years.”
Though large companies typically have processes and budgets in place to routinely upgrade SCADA software and hardware, midsize and smaller companies can frequently find themselves behind the curve.
Scaling up for Big Data
Modern SCADA systems can offer many benefits, says David McCarthy, president and CEO of system integrator firm TriCore Inc.:
- Greater software and hardware reliability;
- More computing power;
- Use of less expensive thin clients;
- Reporting services that are integrated and run on browsers;
- Simpler ways to expand or modify systems; and
- High-resolution HMI displays that improve operator awareness and control
“There’s also been a big evolution in data historians,” explains McCarthy. “They can now process up to 150,000 samples a second, so companies can see properties they never even knew existed. And with the cost of storage dropping dramatically, you’re able to analyze operations and see outliers that can tell you if the process is drifting. You need Big Data to do that.”
McCarthy says SCADA systems used to be operator-oriented, but now companies are focused on uptime. “It didn’t used to matter so much if the SCADA system went down; the production equipment continued to run. But now if it goes down, it can take the whole plant down. The plant can’t run because production data can’t be recorded.” Though this is particularly important for regulated industries like pharmaceuticals or food and beverage, it applies to any company that wants to track and trace its products and processes.
If you’re planning a SCADA upgrade, McCarthy says, “The first thing to focus on is what data is important to the operation and how to report and record it. You must also plan for growth, because people will always want more data.
“You need to look really hard at product support,” McCarthy adds. “How readily does a software vendor manage compatibility issues, upgrades and patches, and how do hardware companies handle replacement parts? Finally, with everything intertwining from a network perspective, consider how factory systems can be kept separate from business systems to ensure plant-floor security.”
Start with the business goals
“It’s not just about what the technology can do when you’re considering SCADA and HMI upgrades,” says Krajewski. “If you don’t start with the business goals, there’s little chance of achieving them. Unfortunately, the people charged with managing production systems have been measured more often on uptime or productivity than achieving the goals of the business.”
Krajewski says the idea that SCADA systems should be focused on business performance started with the oil and gas industry, and it is often thought that only companies with big budgets can justify that approach.
“That’s changing now because the results have been compelling and the technology has evolved so you don’t have to hire expensive specialists to do it,” Krajewski says. “Vendors have also responded—not only with new, more affordable capabilities in their products, but by helping system integrators learn to work with the products.”
One example of this new business focus is the way HMI screens are being reorganized to provide a hierarchy of data. “Level 1, the highest, shows a global overview of system awareness and what actions might be needed,” Krajewski says. “Level 2 screens are focused on process deviations, while level 3 displays are more like typical P&ID displays. Level 4 indicates trends and alarms.” The goal of this situational awareness approach to HMI is to enable operators to see what’s happening more clearly so they can take the right actions more quickly.
“Today’s HMI screens are designed to help operators perceive what’s happening in the production process, provide a context for that information, identify the potential impact of these performance indicators, and empower operators to make decisions,” Krajewski explains. “Real-time business performance is being pushed down to the real-time operating teams. As that happens, business results are going to improve.”
Connectivity and convenience
“Today, companies are looking for the same kinds of apps and conveniences they find with their tablets and smartphones,” says Brian Oulton, vice president of strategic marketing for Belden Industrial Networking. “When this kind of capability is applied to industry, the business results can be significant, both in productivity and business agility. So don’t just upgrade your SCADA, rethink it.”
As part of that, you should think about where the information is coming from and going to, along with how much and how fast it’s getting there, Oulton adds. “While you probably don’t need to do a lot of math here, the exercise will give you a pretty good idea if your industrial and enterprise network infrastructures are set up to handle that and all of the other kinds of control and information traffic. It’s a great time to move that ad-hoc network to a better design—one with room to grow, plenty of bandwidth, ease of maintenance and appropriate security,” he says.
With all this connectivity, security has become the elephant in the room for manufacturers. “Hackers are getting into SCADA systems all the time,” says Mario Mitchell, product manager for the electronics business of automation vendor Parker Hannifin. “SCADA system infrastructure needs to be secure. You need to think long and hard about security when you’re setting up your networks. You also need a very good IT staff to protect the data, and to set firm rules for who can have access to it and how.”
Do-it-yourself tools
Off-the-shelf tools, many of them based on the Microsoft .NET platform, are allowing more companies to create their own SCADA systems, according to Chuck Karwoski, owner of CimQuest InGear, which makes communications software for PLCs. New browser-based tools cut programming time for developing HMI displays and allow the same system to be replicated in multiple facilities, both domestic and global, without additional licensing fees. They also make it easier for users to create their own applications with consumer-type functionality.
But any upgrade, whether managed in-house or handled by a system integrator, is not to be undertaken lightly, says Karwoski. “You need to determine if a SCADA upgrade will enable your company to make more money, produce fewer defects, reduce rework or increase production. It has to be about the business goals to justify the investment. You need a long-term plan for how to do it, how long it will take to get there, and what’s the ROI. Otherwise, if it’s not broken, then don’t fix it.”
SCADA systems used to be closed, custom-made applications that could only be changed by the person or company that created them. They often ran on high-end servers that required experienced software engineers to manage, which added another layer of cost and complexity. “But you don’t have to be a network jockey to work with today’s SCADA platforms,” says Bruce Krebbers, control system engineer with system integrator Panatrol.
“Key capabilities to look for in any SCADA upgrade,” says Krebbers, “are tools for HMI graphics that are easy to learn and let you become productive quickly; the ability to easily expand the system for facility changes and growing data needs; an open format such as SQL Server for data storage, which means you don’t need to buy a third-party package for data analysis; and the ability to interface with software and hardware from multiple vendors.”
“If you’re considering a change from one platform to another,” Krebbers adds, “there will be a cost. But if the new platform allows you to make changes easier and faster, then every additional project will cost less.”
Picking the right platform, partners
Parker Hannifin’s Mitchell says finding the right SCADA platform depends on what you’re trying to accomplish. “Some products may only track certain data sets, but if your business is evolving you’ll need a SCADA platform that can evolve with it.”
“People not only want more data now, but they want to be able to analyze it to find out where the bottlenecks are in their production systems,” adds Krebbers. “They want to know how many times systems failed last week or last month, and that requires more data so they can detect the problems and fix them.”
Depending on the complexity and amount of information the SCADA system needs to manage, companies will often hire a system integrator to manage an upgrade. “Seek out somebody who’s done it many times before,” counsels TriCore’s McCarthy. “There are many pieces and parts to a SCADA upgrade and a lot to understand in terms of software, hardware, networks, services, storage and the flow of information to various parts of the business. It’s easy to do a SCADA upgrade poorly, so pick a good partner.”
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