High
−
level Instructions
3
−
761
Outline
This instruction carries out PID processing using data table.
Program example
Ladder Diagram
Boolean
Ladder Diagram
Address
Instruction
S
Trigger
F355 PID, DT 10
10
R0
10
11
ST
R
0
F355
(PID)
DT
10
S
Starting number of PID parameter area (30 words)
Operands
Operand
Relay
Timer/Counter Register
Index
register
Constant
Index
modifier
Operand
WX WY WR WL
SV
EV
DT
I
K
H
f
modifier
S
N/A N/A N/A N/A
N/A
N/A
A
N/A
N/A N/A N/A
N/A
Description
PID processing is performed to hold the measured value specified by S+2 at the set value S+1, and the result
is output to S+3.
Derivative control or proportional
−
derivative control can be selected for the PID processing mode.
Set the PID processing coefficients (proportional gain, integral time and derivative time) and the processing
mode and cycle in the parameter table. PID processing will be performed based on these settings.
Types of PID processing
Reverse operation and forward operation
When a process has been changed, the vertical direction of the output can be selected.
If the measured value drops, “Reverse operation” is specified to boost the output (heating, etc.).
If the measured value increases, “Forward operation” is specified to boost the output (cooling, etc.).
Derivative type (PI
−
D) / Proportional
−
derivative type (I
−
PD)
Generally, with “derivative PID control”, when a set value is changed, there is increased fluctuation in the
output, but convergence is faster.
Generally, with “proportional
−
derivative PID control”, when a set value is changed, there is less fluctuation in
the output, but convergence is slower.
next page
PID processing
5
F355
(PID)
A: Available
N/A: Not Available
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: [email protected]
Summary of Contents for FP-X
Page 1: ...Phone 800 894 0412 Fax 888 723 4773 Web www clrwtr com Email info clrwtr com ...
Page 2: ...Phone 800 894 0412 Fax 888 723 4773 Web www clrwtr com Email info clrwtr com ...
Page 24: ...Phone 800 894 0412 Fax 888 723 4773 Web www clrwtr com Email info clrwtr com ...
Page 1333: ...5 245 Phone 800 894 0412 Fax 888 723 4773 Web www clrwtr com Email info clrwtr com ...