Process variable: Difference between revisions
No edit summary Tags: Reverted Mobile edit Mobile web edit |
m Reverted edit by 176.29.150.243 (talk) to last version by Kvng |
||
Line 1: | Line 1: | ||
{{Short description|Value of a given part of a monitored or controlled process}} |
{{Short description|Value of a given part of a monitored or controlled process}} |
||
{{about|the engineering indicator|the mathematical concept used in thermodynamics| |
{{about|the engineering indicator|the mathematical concept used in thermodynamics|process function}} |
||
{{more citations needed|date=May 2022}} |
{{more citations needed|date=May 2022}} |
||
Latest revision as of 12:36, 12 July 2024
This article needs additional citations for verification. (May 2022) |
In control theory, a process variable (PV; also process value or process parameter) is the current measured value of a particular part of a process which is being monitored or controlled. An example of this would be the temperature of a furnace. The current temperature is the process variable, while the desired temperature is known as the set-point (SP).[1]
Control system use
[edit]Measurement of process variables is essential in control systems to controlling a process. The value of the process variable is continuously monitored so that control may be exerted.
Four commonly measured variables that affect chemical and physical processes are: pressure, temperature, level and flow.[citation needed] but there are in fact a large number of measurement quantities which for international purposes use the International System of Units (SI)
The SP-PV error is used to exert control on a process so that the value of PV equals the value of the SP. A classic use of this is in the PID controller.
References
[edit]- ^ B. Wayne Bequette (2003). Process Control: Modeling, Design, and Simulation. Prentice Hall Professional. p. 5. ISBN 9780133536409.