Modular automation in water technology

Four steps to modular automation

There’s little you can do about the wide fluctuations in the consumption and the quality of raw water. But what you can do is to ensure that your water treatment handles this intelligently. This is where the networked Industrial Internet of Things comes into play, together with modular automation from Festo.

Modular automation with CPX

Festo has made automation technology smart. Thanks to digitalization, today we can network automated modules with each other at the field level, safely and reliably, and get them to work with each other. The key phrase here is: “intelligent components” that can be combined with each other flexibly, based precisely on needs and on requirements. Each module has all the automation elements needed to handle its own processes.

The linchpin for the centralized signal processing and functional control is our CPX automation platform. Here, you can have much better and more economical control over fluctuating water consumption and raw water quality than with a central control system. If anything is missing, it can simply be docked and activated, whether for a filter system or further process steps (numbering up rather than elaborate scaling up).

Intelligence at the Field Level

Comparison: Modular versus Centralized

Water technology: modular automation

Up until now, the design and engineering of process-related systems has generally run like this: you define a production quantity to be produced within a predefined time and then you set up a process to achieve this. The whole thing is controlled and monitored by a centralized control system. This works well as long as the required production quantity remains the same.

But that is precisely the opposite of what happens with you, or there are quality fluctuations in the raw water. Intervening in such centralized automation is extremely laborious, because it requires a modification of the complete process and automation technology. In addition, you need someone who is proficient in precisely this special design and its programming. On top of that, reduced throughput can impact the product quality and jeopardize the profitability of the system. And lastly, service and maintenance are made more difficult and more expensive, because you continually have to shut down and restart the system.

The concept of modular automation provides an effective alternative for all industries that treat and use water. Each networked system module is a functional unit in its own right, works independently, and contains the complete controller from Festo. This means that you can simply connect and disconnect it as required, quickly and cheaply. As a result, changes to the production quantity can be implemented flexibly. There is no need for any reprogramming or reconfiguration of the application software. And maintenance costs also drop significantly.

Practical Example: Beverage Production

Beverage production

The raw water has a different composition, depending on the location of the factory. Occasionally, contamination can occur. Because of that, corresponding water treatment steps are necessary to ensure that you have high quality water for use in production. This requires a precisely fitting combination of filtration systems: gravel filters, ion exchangers, ultrafiltration or reverse osmosis systems, etc.

Modular automation here has a clear advantage, as it can adjust itself quickly to meet changing circumstances and the required filtration modules can easily be integrated. Plus, each of these modules already contains the necessary automation functions that have been created through the remote I/O system with integrated PLC from Festo. As a result, they can be expanded simply and based on exact needs.

Your path to modular automation

Using water filtration as an example, these diagrams show in just four steps how you can make a modular, decentralized automated solution out of a conventional, process-based large-scale system with centralized automation. For this example, we will show a typical water treatment plant that was designed using exactly the previously defined requirements and would be difficult to adapt (to scale down or scale up). Modular automation makes a flexible system out of it, allowing you to adjust the production quantity simply and quickly, by removing modules (numbering down) or by adding modules (numbering up).

For our example, we’ll illustrate the water filtration system design that was once commonly used, with a central controller and control system. The valve manifold is connected to it over a fieldbus as a remote I/O system with the integrated pneumatics part. The components for controlling the field devices are installed in the control cabinet.

Step 1: Break it up into subprocesses

Conventional water treatment systems of this type can be modularized in a simple way. To start with, the overall process is broken up into subprocesses. A module is defined for each subprocess, which contains all the mechanical and automation technology components that are needed for autonomous operation.

Step 2: Modularizing automation

The automation is modularized in the same way. The control cabinet components and the central controller (the process-based application software) are divided up in such a way that each module is equipped with its own controllers, remote I/O components, and pneumatic controllers.

Step 3: Coordinating the complete system

After the modules have been connected together to form a process-based system, each module makes its specific functionality available over a data interface, in an encapsulated format. This makes it possible to read out and/or write operating mode, status, process measurement values, alarms, etc., so that the system functions.

In addition, you also need a process management system that coordinates the module functionalities across the complete system and facilitates the guidance of the processes. This, however, can turn out to be a much leaner approach than with central controllers. As has previously been mentioned, the process-related controller functions are already contained in the modules themselves.

Step 4: Flexible adjustment of modular systems

Using the modules described, you can build systems in any design you like in order to meet your current needs and requirements, simply by adding modules that are identical in terms of construction and function. It is flexible from the word “go” and it remains flexible, numbering up instead of scaling up.

Modular automation is relatively simple. With Festo, it is even simpler: our specialized personnel are happy to advise you.

Arguments in favor of modular automation

The described modularization of a previously centrally controlled system is based on the example of water filtration. Fundamentally, however, the principle can be applied to other industry segments. And it is not only system operators that profit from the flexibility that modular process automation from Festo delivers. A modular concept also represents a win-win situation for equipment manufacturers as well.

Benefits for operating companies and OEMs

  • Numbering up/numbering down: Modular automation makes it much easier to implement changes to the entire system. As a result, the engineering is completed more quickly and more economically.
  • Transparency: The individual modules from Festo are precisely defined units with clearly defined functionality.
  • Flexibility: As a result, it is also easy to configure the modules. This simplifies and accelerates the integration of additional process steps.
  • Simplicity: The modules contain their own specific application software. This reduces the complexity of the complete IT landscape.
  • Independence: Festo modules are programmed with CODESYS in accordance with IEC 61131. As a result, there are no license costs and you are free to select the automation hardware of your choice.
  • Synergy: OEMs can produce standardized modules, even in small quantities, and thoroughly test them before delivery. In this way, you benefit from economies of scale in terms of production and assembly; you drive down your costs and you can service the market at the right time.

Water technology is just the beginning

It’s anticipated that the design and engineering of process-based systems will change fundamentally sooner rather than later. With an eye on the Industrial Internet of Things, the NAMUR Recommendation NE 148 has already formulated the “automation requirements relating to modularization of process plants.” Across the whole process industry, equipment operators and manufacturers should test to see whether modular concepts are possible with their current systems.

White paper: systems based on the Lego principle

We explain the changeover to modular automation with process-based systems using the example of water filtration, in a clear and comprehensive white paper.

You can download the PDF here.