Related Articles

• Programmable automation controllers (PACs)
  When ARC Advisory Group analyst, Craig Resnick, proposed a new term for an emerging class of programmable devices for automation in 2001, few expected such growth of related technologies. The market extends beyond the formal name—programmable automation controllers (PACs). Some vendors reject the word, yet satisfy the PAC feature set with newer programmable logic controllers (PLCs). Control Engineering
• Feedback loops control discrete, continuous processes
  Arguably, the most basic tool of the control engineering profession is the feedback loop, shown below. It consists of five fundamental elements: This measure-decide-actuate sequence repeats as often as necessary until the desired process condition is achieved. For a continuous process, a feedback loop attempts to maintain a process variable (or manipulated variable) at a desired value known as ... Control Engineering