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Many PID loops control a mechanical device (for example, a valve). Mechanical maintenance can be a major cost and wear leads to control degradation in the form of either stiction or backlash in the mechanical response to an input signal. The rate of mechanical wear is mainly a function of how often a device is activated to make a change.
The control action is the switching on/off of the boiler, but the controlled variable should be the building temperature, but is not because this is open-loop control of the boiler, which does not give closed-loop control of the temperature. In closed loop control, the control action from the controller is dependent on the process output.
Process control instrumentation and designation (names, numbers, unique tag identifiers), including: Valves and their types and identifications (e.g. isolation, shutoff, relief and safety valves, valve interlocks) Control inputs and outputs (sensors and final elements, interlocks)
Active control requires actuators that require energy and may operate in a time-dependent manner. [1] Active flow control includes steady or unsteady suction or blowing, [2] the use of synthetic jets, valves and plasma actuators. Actuation may be pre-determined (open-loop control) or be dependent on monitoring sensors (closed-loop control).
The control action is the switching on/off of the boiler, but the controlled variable should be the building temperature, but is not because this is open-loop control of the boiler, which does not give closed-loop control of the temperature. In closed loop control, the control action from the controller is dependent on the process output.
The basic architecture of a motion control system contains: A motion controller, which calculates and controls the mechanical trajectories (motion profile) an actuator must follow (i.e., motion planning) and, in closed loop systems, employs feedback to make control corrections and thus implement closed-loop control.
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Physical Interface Device, a class of a USB device; PID controller (proportional-integral-derivative controller), a control concept used in automation; Piping and instrumentation diagram (P&ID), a diagram in the process industry which shows the piping of the process flow etc. Principal ideal domain, an algebraic structure