Glossary of Terms
Portion of the valve that may be pneumatic or motor driven, used to open and close automatic valves.
The difference between the average value of a sinusoidal variation and the maximum or minimum value.
The ratio of the amplitude of a system's response to its forcing function's amplitude when the forcing function is a continuous sinusoid; a form of dynamic gain.
A controller that operates on continuous signals such as voltages, pressures or currents; this is a common older type of controller as distinguished from a digital controller.
A decrease in the strength of a signal by a system component.
A device which operates to correct or limit the deviation of a variable from a reference value.
The use of automatic control devices in a process so that human supervision is minimized.
The amount of energy or material which must be added to a closed system to cause unit change in potential; the partial derivative of content with potential.
A series of stages in which the output of one is the input to the next.
Automatic control involving ‘cascading’ of controllers; that is, having one controller's output as the input to the next controller instead of manipulating a process variable directly.
The portion of the control element which determines the difference between the set point and the measured feedback ...