Roadmap to the E-Factory

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Roadmap to the e-Factory

of an electrical control signal into a mechanical or physical action. PLCs are

used to do everything: turning on and off valves, actuators, pumps, doors,

alarms, and other machines. In their first generation, PLCs were electrome-

chanical switches; today, they are personal computers with custom semicon-

ductors and circuit designs. PLCs can be found sprinkled throughout a

manufacturing plant and usually networked together.

Machine controllers are also at the bottom of the hierarchy. These are the

control computers that the maker of a piece of manufacturing equipment

would incorporate into the machine design. These used to be custom electronic

devices with capabilities limited to sensing and controlling basic machine

functions. ...