Control Engineering Top 5 most read articles online, for Sept. 10 to Oct. 9, the competition to make the first PLC, the PLC’s future, System Integrator Giants of 2014, cascade control fundamentals, and open- vs. closed-loop control. Link to each article below.

1. Inside the competition for the first PLC

The race to develop the first programmable logic controllers was underway inside General Motors’ Hydra-Matic Transmission Division in Ypsilanti, Michigan, in 1970. Three finalists had very different architectures. 

2. Future of the PLC

PLCs are evolving and continue to be the best option for a variety of industrial automation applications. Greater programming flexibility and ease, scalability, more memory, smaller sizes, very high-speed (Gigabit) Ethernet, and built-in wireless are among evolving programmable logic controller features. 

3. System Integrator Giants of 2014

The 2014 System Integrator Giants boast a $396 million increase in system integration revenue, a greater concern for the economy’s impact on the automation integrator market, and a strong belief in educational and mentoring programs for employees. 

4. Fundamentals of cascade control

Sometimes two controllers can do a better job of keeping one process variable where you want it. 

5. Open- vs. closed-loop control

The list was developed using CFE Media’s web analytics for stories viewed on controleng.com, from September 10 to October 9, for articles published within the last two months.

– Chris Vavra, production editor, CFE Media, cvavra@cfemedia.com.

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