PID control is one of the most commonly used closed-loop control mechanisms in industrial control systems. PID controllers work great when applied and configured correctly, and they are often viewed as a sort of magic box that can solve any process control problem. To successfully apply and tune these controllers, it is important to understand how they work, the math behind them, and the nuances of the specific implementation by various manufacturers. This post provides an intuitive look at how a PID works before getting into the math.
Equipment manufacturers, engineering, procurement and construction (EPC) companies, and power and process plant owners and operators commonly face the challenge of keeping their fleet, machinery, and other assets working efficiently while reducing the cost of maintenance and time-sensitive repairs. Considering the aggressive time-to-market required for industrial products and services, it is crucial to identify the cause of potential faults or failures before they have an opportunity to occur.
UL-508A certification for industrial control panels is a requirement in most jurisdictions and a standard many OEMs voluntarily choose to follow. There is a common misconception that a UL-508A certified panel shop can certify any panel they build. However, panels must also be designed to UL-508A standards to be certified. Because of this, it’s important to make sure your design is compliant with the 508A standard before approaching a panel shop to build and certify it. Here are a few things to consider to ensure your design is UL-508A certification ready.
Successful automation projects provide increased value by improving operations, safety, or quality; reducing costs; or directly increasing profitability. The investment made to achieve one or more of these goals can be significant, and that investment will only pay off if the project is successful.
We often see requirements for backup PLCs in specifications as clients understandably aim to improve their control system reliability. Adding a redundant controller can be a good choice as part of a holistic approach to system availability and reliability. When specifically addressing PLC failures as a cause of system downtime, here are a few tips to keep in mind:
In today’s manufacturing world, businesses are rapidly adapting smart manufacturing and Industrial Internet of Things (IIoT) technology that amass valuable data from all aspects of the organization for faster, smarter decision making. According to the Industrial Ethernet Book, “by 2020 there will be an estimated 20.8 billion devices in the IoT, and more than 30 billion devices will be wireless connected.” However, this digital transformation also means that the line between information technology (IT) and operational technology (OT) is blurring more and more with every passing every year.
Part 1 of this series introduced the concepts of Proportional (P), Integral (I), and Derivative (D) terms in a PID loop to automatically control a process so that it can react to unforeseen changes. The changes can be either in the Process Variable (PV) or Setpoint (SP) and it is brought under control by altering the Control Variable (CV). In this blog post we will explore the role played by each term using simplified examples and basic arithmetic.
NXP Semiconductor was facing several issues with an aging control system for its ultra-pure water (UPW) plant in Chandler, AZ. The Allen-Bradley PLC-5 control systems were state of the art when installed in the late 1990s, but most of the components are now discontinued or deemed “active mature.”
The two main problems NXP Semiconductor was facing with the system included:
This month, our ICS Cyber Security Survival Guide was featured in The Industrial Ethernet Book– the only internationally distributed journal dedicated to industrial Ethernet and wireless technologies. As the respected Internet of Things authority, The Industrial Ethernet Book is a trusted resource for forward-thinking plant manager and network administrators in manufacturing.
Why is it when you send out a request for quotation (RFQ) to potential vendors for an automation project, you end with a stack of widely different prices and proposals that are about as comparable as apples and oranges? You’re probably not going to accept the highest bid with its extraneous add-ons, but if you choose the lowest bid, there’s a strong likelihood you’ll end up with multiple change orders after the project begins. What’s the secret to setting up your automation project for success right from the start?