A Programmable Logic Controller (PLC) is an electronic device used to monitor or control production processes. It is a device that a user can program to perform a series or sequence of events. These events are triggered by inputs received at the programmable logic controller through delayed actions such as time delays.

Automation software and hardware advances reduce programming tasks and provide more built-in configurability, scalability, background communication among software components, simulation/digital twin capability, and usability. 

It’s been 51 years since the birth of the Programmable Logic Controller. We look back at the history of thePLCand how replacing hard wired relay systems changed theworld of manufacturing.