Topic summary
Programmable logic control
Extracted from the Wikipedia article Programmable logic controller.
Allen-Bradley
In a parallel development, Odo Josef Struger is sometimes known as the "father of the programmable logic controller" as well. He was involved in the invention of the Allen-Bradley programmable logic controller. Prior to the release of the IBM "Personal Computer" in 1981, these devices were commonly known simply as "Programmable Controllers", or "PC's. But rapid expansion of the personal computer industry in the early 1980's, the abbreviation "PC" was rapidly and universally accepted as a reference to "Personal Computers". Odo was later credited with coining the "PLC" acronym to distinguish these two technologies, And the inclusion of the word "Logic" was an easy choice as "Ladder Logic" had already been accepted as the name of the programming language. Allen-Bradley (now a brand owned by Rockwell Automation) went on to become the dominant PLC manufacturer in the United States during his tenure. Struger played a leadership role in developing IEC 61131-3 PLC programming language standards. Allen-Bradley's PLC-5 family, preceded by the 1774-PLC (released in the 1980's, was the first modular design found in modern-day systems.