PID controllers ready to talk if you're listening

Posted: MAY 11, 2022

A proportional-integral-derivative controller, PID controller for short, is a control loop mechanism known for use in industrial control systems and those requiring continuously modulated controls.  However, PID controllers can deliver more than just control. They are ready to talk about machinery health and process health if you know how to listen.

PID controllers can reveal hidden changes in machine wear, flow restrictions, feed stock quality, contamination, corrosion, utilities, ambient conditions, fouling of surfaces, miscalibration, poor repairs, and many more. Often these hidden changes are transient, making them even more elusive. But in every case, there are root causes behind every movement, and the first step to finding these root causes is to create visibility.

PID controllers are ubiquitous – nearly every industry, site, building, and process has them. They are the foundation for monitoring a key measured variable and controlling it. Inherently a PID controller measures the efficiency of machinery and processes. For example, the speed of a pump should deliver an optimal amount of liquid flow. With today's prolific expansion of digital resources in manufacturing, we use pattern recognition logic to watch PID controller strain and flag the start and end of changes into transactional data. Actionable alerts notify operating personnel, suppliers, vendors, and process experts across an enterprise. A wide approach of data sharing can elevate these new data streams to solve problems previously hidden or misunderstood.

To calculate PID controller strain, divide the manipulating variable (MV) by the resulting process variable (PV). The ratio of MV/PV indicates a controller's strain.

Many manufacturing operations today are already storing years of PID controller performance data in their time series historian systems. This historical data is super valuable if you apply analytics like PID controller strain to it and begin to reveal the hidden events that occur in your operation.

If you're looking for new data streams to maximize process health, visit the post PID Controllers Ready to Talk If You're Listening, and check out this on-demand webinar.