دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a device used to manage, or control, another device or devices that govern the operation of a system or process. An operator, using an attached computer, can program the controller to maintain a given set of desirable circumstances and to respond to changes or upsets in the system or process using ladder logic, which is a logic system that operates much like the rungs on a ladder-that is, before the next rung on the ladder can be scaled, the controller must determine that certain conditions are met on the current rung.