Since it first appeared in UK manufacturing in the 1980s, supervisory control and data acquisition (SCADA) software has been a core component of food factory control and data visualisation networks.
Bigger and more complex operations, in particular, continue to use SCADA, and multiple suppliers are still actively selling evolved versions of the technology.
At the same time, it is not uncommon to hear the opinion that SCADA is ‘past its sell-by date’ or, more melodramatically still, ‘SCADA is dead’. So, why is opinion so divided?
Founder of the consultancy Food Scientific Services, and former manager of the National Centre for Food Manufacturing at the University of Lincoln, Mike Dudbridge has real doubts about the current relevance of SCADA in its traditional form.
“Now, it’s all about having the capability to upload data to the internet, and it links in to the move towards the Internet of Things [IoT],” he says.
“Data flow and signals are taking that route rather than a dedicated route. That is where the developments are coming.”
Specialist information (Back to top)
Dudbridge looks back on his own experience in the food industry and the role he saw SCADA playing there.
“It was something run by engineers to provide data about machine performance, or by production personnel for their own data and for control, but it was always very specialist information and a very local phenomenon,” he says.
“Nowadays, everyone in the business, from the sales team to the accountants, wants data from the factory on potentially dozens of graphical user interfaces (GUIs),” Dudbridge explains. “Data from the same sources will be processed in slightly different ways.”
To illustrate some of the challenges arising from the clash between older technologies and newer expectations, he describes how one company removed SCADA from its production line because it was “creating more problems than it was solving”.
While the machinery was relatively new, he explains, the technology behind it was not as advanced. “They were trying to push the line faster, and they stepped outside the specification of the SCADA system.”
But, he warns: “When they fell back on line operation from individual machine control points, they started to suffer from the lack of data.”
While the challenges may not usually be as extreme – or urgent – as this example, many growing businesses come up against a similar dilemma. They want to radically overhaul SCADA or wider data processing systems, but face obstacles of their own.
Mark Swainson, principal lecturer in food manufacturing at the University of Lincoln, says: “There’s a lot of innovation around the food industry, but much of the technology is 20 or even 30 years old.
“Businesses are expending so much energy on day-to-day production that they can’t afford to invest in new control or data-handling technologies.”
At Rockwell Automation, solution architect team leader Grant Coffin points out that there have been reliability and support problems with some older SCADA systems.
“Where they’re Windows-based and reliant on Windows 95 or XP, for example, reliability can become a real problem,” he says.
“Any manufacturer needs to think about the lifecycle of the plant. Poor implementations of SCADA do exist, but that’s usually down to the implementation rather the product itself.”
More generally, Coffin highlights some of the challenges facing industries such as food and drink where automation may have developed over time.
“A fair amount of automation installed in the UK consists of legacy equipment, raising the question of how you extract data in order to make better decisions, increase yield, improve consistency, and so on,” he says.
“If there is a bad batch today, we don’t want to have to spend tomorrow analysing why it happened,” Coffin argues. “You want to be able to spot the trend and correct it in real time.”
Swainson at Lincoln points out that some plants require barely any human intervention (as in many dairies), with many processes “on algorithms”.
Others are more labour-intensive, requiring management tools to track the efficiency of the workforce and overall equipment effectiveness (OEE), for example.
“But from what I see of SCADA’s role, you’re going to need these elements in any case, whether you have a wired or wireless system for capturing and transferring that data,” he says. “But of course, it may not be identified as SCADA.”
SCADA definitions (Back to top)
Indeed, what you consider to be the current and future – fate of SCADA could come down to your own definition of what it is.
At Rockwell Automation, Coffin points out that SCADA has evolved over the 25 or 30 years of its existence, with particular benefits for its visualisation options and real-time trending.
He points to OEE as one of many areas where SCADA-type functions play a central role.
“When it comes to OEE and improving efficiency, you have to understand where your losses are,” says Coffin. “And you can only do that if you fully understand what is happening at each stage in the process.”
A factory data ‘pyramid’ might have automation controllers and sensors at level one, with level two shared by SCADA, managing visualisation, alongside manufacturing information systems (MIS) with historian and data analysis functions.
Above this sit manufacturing execution systems (MES) as level three, with some sort of enterprise-wide system as the top layer.
“SCADA and MIS have converged,” Coffin says. “There’s been a blurring of the different functions at the second level, and that’s where this idea originates that SCADA is ‘dead’.” In fact, its functions will often simply have been distributed around a wider architecture.
Different providers joint the factory automation and control carcass along different lines. Rockwell has its FT View SE product covering SCADA duties, with FT Historian and VantagePoint (for analytics) providing other MIS functions.
European supplier Copa-Data has the four parts of its zenon software family focused on analysis, supervision, operation and logic. It characterises zenon Supervisor as “an independent SCADA system”.
In announcing the launch of its own version of the software, developed in conjunction with Copa-Data, automation specialist ABB highlights the SCADA system’s value to machine builders in extending “communications, machine-to-machine connectivity and application control possibilities”.
It also underlines its relevance to food and drink and to the much-discussed IoT and Industry 4.0.
Referring to the brewing business, Copa-Data makes the point that these systems are scaleable, so that a start-up microbrewery can expand without having to move to new automation software.
Equally, the company says, its modules work just as well with programmable logic controller-based architecture as with a system based on an embedded industrial PC.
Plant visualisation tool
At software company Products4Automation, which supplies the Italian Movicon SCADA system, director Paul Hurst is understandably bullish about the technology.
“SCADA as a plant visualisation tool and a monitoring platform, which can provide accurate data management and straightforward controls, is pretty much unbeatable in terms of cost-versus-functionality and flexibility,” he maintains.
“Any in-house team or integrator looking for cost-effective monitoring, energy management, mobile remote access and so on, is certainly going to choose a SCADA system of one sort or another, whether it is independent of the major factory automation hardware vendors or not,” Hurst argues.
Nor does he see the prospect of Industry 4.0 and its international equivalents as a risk to the relevance of these software systems.
“Using SCADA-type products will help make Industry 4.0 a reality,” he says. “They are enabling technologies, and while people need to see plants on a dashboard, they will almost certainly remain relevant and required.”
Rockwell Automation talks a lot about the Connected Enterprise, and one of the areas where it sees convergence is between information technology (IT) and operational technology (OT), which have – over the years – stayed fairly separate. But Big Data is, by definition, big.
“The amount of data can be overwhelming,” says Coffin. “It needs to be contextualised, so that the right data goes to the right people.”
The OT/IT divide (Back to top)
The OT/IT divide raises another interesting point. “Users who don’t want to install their own technical infrastructure are increasingly using software as a service [SaaS] with cloud-based hosting,” he says.
“The beauty of this is that it is scaleable. Cost is always an issue, especially in food and drink, but in relative terms, systems such as SCADA and MIS in the OT world are significantly less expensive than an equivalent in the world of IT.”
Ultimately, those who predict the demise of SCADA may well be like those business or political leaders who promise to abolish entire tiers of bureaucracy in this or that organisation. The idea sounds very attractive, when in fact many – or most – of those responsibilities will simply be picked up by someone else with a different job title working twice as hard as before (and possibly for half the money).