ISO 15519-2:2015 プロセス産業の図の仕様—パート2：測定と制御 | ページ 6

3.1.1

actuator

functional unit that generates from the controller output variable the manipulated variable to drive the final controlling element

Note 1 to entry: If the final controlling element is mechanically actuated, it is controlled via an actuated drive. The actuator drives the actuating drive in this case.

Note 2 to entry: See Annex E for the relationship between related terms.

[SOURCE:IEC 60050-351:2013, 351-28-07]

3.1.2

closed-loop control

process whereby one variable (quantity), namely the controlled variable is continuously measured, compared with another variable (quantity), namely the reference variable, and influenced in such a manner as to adjust to the reference variable

Note 1 to entry: Characteristic for closed-loop control is the closed action in which the controlled variable continuously influences itself in the action path of the closed loop.

[SOURCE:IEC 60050-351:2013, 351-26-01]

3.1.3

control function

manipulation via the final controlling element of process media or process objects in order to bring the media or object into a condition or state defined by the process control system on basis of measured process variables and pre-defined values

3.1.4

control loop

assembly of elements incorporated in the closed action of a closed-loop control

[SOURCE:IEC 60050-351:2013, 351-26-11]

3.1.5

final controlling element

functional unit forming part of the controlled system and arranged at its input, driven by the manipulated variable and manipulating the mass flow or energy flow

Note 1 to entry: If the final controlling element is mechanically actuated, an additional actuator (positioner) is used in some cases.

Note 2 to entry: The output variable of the final controlling equipment is usually not free from feedback. The interface between the actuator and the final controlling element should therefore be selected in such a way that the manipulated variable is not affected by feedback from the final controlling element.

Note 3 to entry: See Annex E for the relationship between related terms.

[SOURCE:IEC 60050:2013, 351-28-08]

3.1.6

manipulate

to change flows of mass, energy, or information by means of a final controlling element

Note 1 to entry: Manipulating can be affected continuously or by switching operations.

Note 2 to entry: In control engineering, the final controlling element is regarded as belonging to a process.

[SOURCE:IEC 60050-351:2013, 351-22-08]

3.1.7

open-loop control

process in a system whereby one or more variables (variable quantities) as input variables influence other variables (variable quantities) as output variables in accordance with the proper laws of the system

Note 1 to entry: Characteristic for open-loop control is the open action path or in case of a closed action path the fact that the output variables being influenced by the input variables are not continuously influencing themselves and not by the same input variables.

[SOURCE:IEC 60050-351:2013, 351-26-02]

3.1.8

process variable

quantity, quality, or condition of a process media or process object which value may be subject to change and can usually be measured