PLC vs. programmable relay

Sept. 24, 2015

Can a simple application still benefit from a programmable logic controller, or is a programmable relay all it needs?

A Control Design reader writes: I have a small test system that I want to put error proofing on. The sensors are actuated in a very simple extend-and-retract sequence. The application only has four inputs and three outputs. Because it’s such a simple application, how do I decide whether to use a PLC or a programmable relay?

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About the Author

Mike Bacidore | Editor in Chief

Mike Bacidore is chief editor of Control Design and has been an integral part of the Endeavor Business Media editorial team since 2007. Previously, he was editorial director at Hughes Communications and a portfolio manager of the human resources and labor law areas at Wolters Kluwer. Bacidore holds a BA from the University of Illinois and an MBA from Lake Forest Graduate School of Management. He is an award-winning columnist, earning multiple regional and national awards from the American Society of Business Publication Editors. He may be reached at [email protected]