Preparing PLC designs for the “Industry 4.0” future

October 13, 2014 // By Graham Prophet
Maxim Integrated has published a white paper which asserts, “We need to talk about the analogue aspects of your design,” - especially as it relates to programmable logic controllers (PLCs). To meet the ambitions of the “Internet of Things”, and “Industry 4.0”, designs need to physically shrink to enable sensing-everywhere and control-everywhere.

However, argues the Maxim paper, reality is not matching up to these goals; there is an “integration divide”. The company says its researches indicate that 30% of systems designers say their next design will be smaller; 50% of engineers say they look to digital circuitry to achieve space savings; however, 85% of PLC module board space is consumed by analogue circuitry and discrete devices.

In its summary of the paper, Maxim says;

“In today's highly competitive global economy, small improvements in manufacturing processes can yield huge competitive advantages. This mindset is driving fundamental transformations across the factory floor.

Manufacturers are deploying the latest sensor technologies, adopting new control architectures, and starting to discover the potential of “big data” and analytics. Often called Industry 4.0, what’s happening in manufacturing is nothing short of a revolution.

For equipment OEMs, this represents a massive opportunity. The number of sensors used to track environmental and process variables continues to increase. This is accelerating the transition to a distributed control architecture, as plant operators seek to reduce bottlenecks and shorten control loops by moving PLCs closer to the processes they control. Ultimately, the promise of improved operational efficiencies and yields will lead to the largest overhaul of plant operations since the invention of the PLC.

This poses a considerable challenge for PLC engineers. To win in this market, system designers will need to pack more I/O and more functionality into enclosures that keep getting smaller. The problem is that there’s relatively little space to be gained from [further] digital scaling of the microprocessor. In today’s advanced PLC modules, analogue and discrete components consume approximately 85% of board space.

Engineers can no longer afford to ignore the obvious problem on their boards. Many of the analogue and discrete components that have worked so well in previous systems are simply too big for Micro PLCs and embedded controllers. The promise of Industry 4.0 will only be realised