Control system w/o feedback
Open loop control system
Control system w/feedback
Closed loop control system
Two types of signals
Analog and digital
Industry control systems
-Process control (Batch and continuous)
-machine control (robotics)
If a plant has more than 999 loops…
Area prefix must be added, ex: 246-PT-010A
If a loop has two or more identical devices….
Add a suffix. Example:
LG-101A
LG-101B
OR
LG-101-1
LG-101-2
Final control element
Device that adjusts controlled variable
Set point
The desired condition of the controlled variable
Process
Any operation that involves a change of mass, energy, dimension, or form
Controlled variable
The condition which is being regulated or maintained (the variable being directly or indirectly measured)
Measured variable or process variable
Condition which yields information about the controlled variable
Measurement
The conversion of a PV into a standard signal (t
The determination of the existence and or magnitude of a process variable.
