When you use a computer every day and discover you need to perform a new task, you don’t automatically go look for a new PC; you seek out software that you can add to your existing machine to expand its capabilities.
It should be the same with supervisory control and data acquisition systems, but that isn’t always the case. Without a sensible pre-planning strategy, organizations can face replacing entire SCADA systems when process or operational structures change.
It simply shouldn’t be that way, especially for manufacturers operating in today’s dynamic marketplace where demands, materials, and processes are constantly evolving. When change happens, requirements for industrial output can shift almost overnight. In an ideal world, software must be capable of adapting instantaneously to it.
The solution is scalability: the ability of SCADA systems and software to upgrade in terms of scope and scale and even to structurally transform and integrate with new process requirements, systems, and equipment.
Traditionally, process automation and control systems were not designed for this kind of agility and flexibility. Once you had a system, you had to work with it — adapting the processes to work with the control system, not the other way around.
Today, new approaches are leading process engineers to create designs that not only deal with today’s requirements but are also built to adapt and change.
Foremost among these is the modular design of SCADA systems, whereby users customize the setup, residing on single or multiple servers in hub-and-spoke configurations or, increasingly, via cloud hosting — in a format that allows for additional software to be “bolted on” and then to work seamlessly. (This Industrial Ethernet Book article provides an overview of approaches to a modular SCADA architecture.)
It’s the same as adding an application to a PC or smartphone. The underlying operating system remains in place, but additional functionality is delivered via the new app, exploiting the power of the original operating architecture.
In scalable SCADA systems, individual modules are added to perform their own tasks, although they may do this by capturing or exchanging data with other modules or enhancing their functionality. And, like apps, they should be quick and easy to put in place and customize for specific requirements.
As Lucian Fogoros notes on the “Wonderware” blog, you can view and build modularity into SCADA systems from several perspectives, according to perceived needs.
For example, the architecture could reflect:
- Functionality — the ability of a system to scale up in size as the business grows without having to change the technology that drives it
- Multiple solutions — the ability to broaden the scope of the architecture, from its original single purpose to multiple functions, while remaining consistent with the architecture and operation of the original
- Horizontal or vertical orientations — the respective abilities to integrate with peer-level systems or to collaborate with different systems across the enterprise
These are not necessarily mutually exclusive approaches but are more indicative of the potential flexibility that can be built into a modular system according to need.
Today, industrial processes must not only be reliable but also more responsive than ever before. They must have SCADA systems that can also flexibly adjust — cost-effectively and quickly — to keep up with the accelerating pace of change.