Glossary
©
National Instruments Corporation
G-3
LabWindows/CVI PID Control Toolkit User Manual
I
Instrument Society of
America (ISA)
The organization that sets standards for process control instrumentation in
the United States.
integral (control) action
Control action in which the output is proportional to the time integral of the
input. That is, the rate of change of output is proportional to the input.
K
K
Process gain.
K
c
Controller gain.
L
lag
A lowpass filter or integrating response with respect to time.
linearity factor
A value, ranging from 0 to 1, used to specify the linearity of a calculation.
A value of 1 indicates a linear operation. A value of 0 indicates a squared
nonlinear operation.
load disturbance
The ability of a controller to compensate for changes in physical
parameters of a controlled process while the setpoint value remains
constant.
M
ms
Milliseconds.
N
noise
In process instrumentation, an unwanted component of a signal or variable.
Noise may be expressed in units of the output or in percent of output span.
