Process control instructions
952
Part III FP Instructions
PID_FB
PID processing instruction
Input variables (VAR_INPUT):
Variable Data type Function
Automatic FALSE: Manual setting of MV possible
TRUE: Automatic PID controlled MV
Forward FALSE: Inverse control (heating)
TRUE: Forward control (cooling)
I_PD
BOOL
FALSE: PI-D control
TRUE: I-PD control
SP Set point value, range 0-10000
PV Process value, range 0-10000
Kp Proportional gain, range: 1-9999, unit: 0.1
Ti Integral time, range: 1-30000, unit: 0.1s
Td Derivative time, range: 1-10000, unit: 0.1s
Ts Sampling time, range: 1-6000, unit: 0.01s
LowerLimit MV lower limit, range: 0-10000
UpperLimit
INT
MV upper limit, range: 1-10000
Input/output variable (VAR_IN_OUT):
MV Manipulated value
Auto-tuning is not possible using PID_FB. For this, use PID_FB_DUT (see
page 953).
The value for MV can be assigned externally
either when the program is
initialized or when the value of Automatic is FALSE.
In order to achieve maximum resolution and minimum dead time beyond
LowerLimit and UpperLimit, their values should, if possible, cover the
entire range of 0–10000.
Description
This implementation allows you to set the parameters of F355_PID directly using arguments:
Data types
To Next Page
Loading...
