If it had a face—and it sort of does—would you recognize supervisory control and data acquisition (SCADA) if you saw it on the street? Would SCADA even recognize itself in a mirror these days?

Chance are, probably not. This is because all the earth-shaking shifts due to data digitalization and the Internet are also turning SCADA on its head, and taking it in entirely new directions. Granted, its conceptual borders were always pretty porous—some water/wastewater users think of its their entire control system, while others consider it limited to just their human-machine interface (HMI), However, even as it continues to display collected information in many applications, the accelerating influence of cloud- and virtualized-computing services and the Industrial Internet of Things (IIoT) are pulling SCADA into strange shapes to perform unfamiliar tasks beyond its traditional jurisdiction.

"Where utilities used to have second and third redundant control and SCADA systems for comprehensive disaster recovery, they're now synching with duplicate systems in the cloud," says Michael Chmielewski, offer management VP, process safety and SCADA, Schneider Electric. "We have one large, U.K.-based gas utility that's talking about moving its whole SCADA system to the cloud. SCADA isn't going to dissolve, but it's going to become more of a secure service deployed out of the cloud."   

 Seeking definitions

"Even as a broad term, SCADA is not a distinct thing anymore. Now it's all about the data, and how what used to be SCADA is converging with and incorporating a whole bunch of new technologies," says Chuck Tommey, P.E., business development manager at A&E Engineering in Greer, S.C., a member of the Control System Integrators Association (CSIA). "On-premise SCADA with servers in racks, Ethernet to PLCs and HMIs are still perfectly valid and will continue for a long time, but we're on the brink of a big mindset change.

"We've all heard about the cloud, IoT and data analytics for 10 years, especially from the information technology (IT) side, but now they're converging with operations technology (OT) on the plant floor. Virtualization, IIoT, cloud computing and data analytics are all part of SCADA, or they can be used to enhance or manage it. This means the most successful end users and companies will be those with well-integrated IT/OT teams or IT departments with significant understanding of OT."

Bob Ell, senior marketing director, oil and gas, Honeywell Process Solutions, adds that, "SCADA technology has been changing for many years, adding PCs, new sensors and data centers, but even though the amount of data coming in now is just crazy, the challenge is still getting something meaningful out of it, and turning data and information to wisdom.

"The SCADA journey is different for each customer depending on their different requirement and levels of sophistication. IT may view it one way, but traditional automation and SCADA hasn't changed the way it connects to distributed assets and controls. Water/wastewater, oil and gas, and power applications have done SCADA for a long time, but now they can use an understanding of the Internet to remove more costs. Likewise, they can use cloud technology to more easily display better information to operators, and help them do a better job, collaborate more, and run their businesses more effectively."

New sandboxes, new shovels

Logically, because the cloud, virtualization and IIoT multiply the connections a SCADA system can have with other systems, they also increase how many different functions it can take on—along with the tools to perform them.

To monitor and control more than 200-megawatts  (MW) of utility-level, solar generating capacity at five plants built by Depcom Power in Scottsdale, Ariz., Vertech, a CSIA-member system integrator in Phoenix, Ariz., developed an innovative SCADA system that could handle each facility's thousands of connected devices from many vendors. They include 15,000 tags, 30 screens, 10 clients, 10,000 alarms, one local Microsoft SQL database, one offsite database and 2,000 historized tags. Besides coping with the volume of tags, Josh McGuigan, Vertech's senior control systems integrator, reports that Depcom's new SCADA system also needed to be robust to cope with new plant rollouts and data levels that can quickly become overwhelming.     

"For the solar power plant SCADA system at Depcom's plants, we used Inductive Automation's standard Ignition software architecture, including one local historian and one connection to a database in the cloud," explains McGuigan. "On a typical site, an Ignition gateway will be directly connected to nearly 100 devices. However, some of those devices act as gateways themselves, so the total system is used to monitor and control around 3,000 devices, which amounts to more than 15,000 I/O tags per site."

McGuigan adds that intelligent reporting, which does more than provide the top 1,000 rows of a database table in a tabular format, is essential for large solar arrays. Using advanced scripting the Ignition Reporting module, Vertech designed a report that analyzes data from hundreds or thousands of strings of solar panels to highlight low-performing equipment and prioritize operations and maintenance team activities.

"Ignition lets us provide a SCADA system for Depcom that improves on the industry's status quo," adds McGuigan. "Users now have more data available and their interface is easier to use, allowing operations and maintenance teams to be more effective in identifying and troubleshooting issues. The analysis of site performance data, which used to be a manual task, is now automated, so any site performance issues are quickly brought to the appropriate people. The system can also be developed and commissioned in record time, allowing us to meet schedules that would otherwise be impossible."

Titus Crabb, P.E., president of Vertech, reports, "We work with Siemens, and they call SCADA the 'digital glue' that connects everything. We agree that SCADA connects the application layer with Internet-based services, which lets it sit between data reporting, dashboards, maintenance, overall equipment efficiency (OEE) and enterprise resource planning (ERP). However, this also lets OT and IT understand each other better, use common databases and tools, know how data flows between the plant and enterprise, break down fear, and learn to trust their network."

Travis Cox, co-director of sales engineering at Inductive, adds that, "SCADA is integrating with third-party applications like web services, business intelligence, machine learning, SQL databases and others. However, they're not just looking at intelligence, but are becoming more homogenous and bigger, and their business is getting more involved, too.  In fact, we're now on the cusp of taking previous polling protocols to PLCs, and using new message-oriented middleware and MQTT publish-subscribe protocol to connect devices, and let any application subscribe to them without needing to go through the usual SCADA system. This new MQTT and IIoT architecture gets SCADA back to the mission-critical role it had in the first place."

Dealing with (big) data

So what can cloud-enhanced SCADA do with its new powers? Probably the most important job is make sense of the buckets of data coming in from all its new connections.

For instance, the reticulated water supply system in Hamilton, New Zealand, consists of one treatment plant that sources water from the WaikatoRiver, and delivers it through more than 1,000 km of pipes to eight reservoirs and more than 150,000 residents in more than 51,000 homes and businesses (Figure 1). The city also runs the Pukete Wastewater Treatment Plant (WWTP). To comply with drinking water standards that New Zealand revised in 2008, including retaining operating records for 10 years, the city had implemented Rockwell Automation's RSView 32 SCADA system 10 years ago, but its manual data recording to Microsoft Exel spreadsheets recently needed upgrading.

“Our previous system was outdated and we required an upgrade to help simplify the process of complying with current water regulations in New Zealand," says Gary Pitcaithly, automation and electrical manager at Hamilton City Council. "Not only that, but we identified the potential for improving operational efficiencies at the plant by implementing an integrated system that aims to increase productivity and reduce downtime.”

As a result, Hamilton implemented Rockwell Automation's latest FactoryTalk software, including its FT View SE, FT Historian, FT Vantage Point, FT Asset Centre and FT ViewPoint, which provides real-time exchange of information throughout applications and organizations for improved business decisions, responsiveness and productivity, reduced costs, and easier regulatory compliance with long-term data storage and automatically generated reports. Staff can also externally manage the system via tablet PCs or smart phones.

“The upgrade has delivered greater ease of use of our system throughout the WWTP," adds Pitcaithly. "The new historian is superior in how it stores data, and makes generating information for vital reports much more efficient. Vantage Point lets us develop reports at will, whether for compliance to water standards or for other needs. They can then be published as web-based reports that are available for anyone authorized to view them.

"FactoryTalk has enabled our team to be more flexible with their time, as we're now able to edit or update reports as we go. We simply store our data directly into Historian and the data spreads directly from the programmable automation controller (PAC) to a human interface. This data is incorporated into spreadsheets for us to interrogate, whether it's on a daily, weekly or monthly basis, to tell us if we've had a breach in turbidity or if chlorine levels aren't what they should be.”

Alan Cone, WinCC marketing manager at Siemens Industry Inc., adds that, "The amount of data coming off devices on the plant floor is the biggest trend affecting SCADA today. The data acquisition piece of SCADA is becoming more important, and plant owners continue to reduce downtime and improve overall efficiency of the plants to compete in a global market. As equipment supplies add more intelligence on the field level devices, this creates lots of data on the health of the operation. This data can be overwhelming if not properly managed. While control is still a key part of the SCADA system, more importance is being placed on the data aspect. In the past, the data was mainly used for reporting needs. Now, the data is used to refine and adjust the running plant in real time.

"Understanding and interpolating the data from the field/factory is very important. WinCC has a historian built into the core system, so an additional package isn't needed to log the data. Siemens also has a reporting tool called Information Server that allows users to access the data in WinCC through a web portal, and write a user-defined report that can bring up-to-the-minute data to the requester. Our Process Historian archives data in WinCC on a separate historian for offsite, long-term storage, or as a single repository to collect data from several WinCC SCADA systems at various locations. Information Server can also be used to report on the data in the Process Historian."