PLCs were originally designed as replacements for:
A)microcomputers.
B)relay control panels.
C)analog controllers.
D)digital controllers.

Question

Quizplus · Accepted Answer

PLCs were primarily designed to replace relay control panels, which were used to control industrial processes in the past. Relay control panels were bulky, expensive, difficult to maintain, and required a lot of wiring. PLCs have become popular because they are smaller, cheaper, easier to maintain, and more flexible than relay control panels. While PLCs can also replace analog and digital controllers, their primary purpose was to replace relay control panels.

PLCs Were Originally Designed as Replacements For