449
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
16 External FX Device – FNC 80 to FNC 89
16.7 FNC 88 – PID / PID Control Loop
11
FN
C30-
FN
C39
R
o
ta
tion and
Sh
ift
12
FNC
4
0
-FNC49
D
a
ta
Op
e
ra
tio
n
13
FNC5
0
-FNC5
9
H
igh Speed
Pr
ocessi
ng
14
FM
C6
0
-F
NC6
9
H
and
y
In
st
ru
cti
o
n
15
FNC7
0
-FNC7
9
Ex
te
rn
a
l F
X
I
/O
D
evi
ce
16
FNC8
0
-FNC8
9
Ext
e
rnal
FX
D
evi
ce
17
F
N
C1
00
-F
NC
10
9
Da
ta
Tr
ansf
e
r 2
18
FN
C
110-FN
C
13
9
Fl
oat
ing P
o
in
t
19
FN
C
140-FN
C
149
Da
ta
O
per
at
io
n
2
20
FN
C
15
0-F
N
C
159
P
o
si
tioni
ng
C
ont
ro
l
16.7
FNC 88 – PID / PID Control Loop
Outline
This instruction executes PID control which changes the output value according to the input variation.
→
For the details, refer to the Analog Control Edition.
1. Instruction format
2. Set data
3. Applicable devices
Explanation of function and operation
1. 16-bit operation (PID)
When the target value
, measured value
and parameters
to
+6 are set and then a
program is executed, the operation result (MV) is stored to the output value
at every sampling time
.
Operand type
Description
Data type
Data register number storing the target value (SV)
16-bit binary
Data register number storing the measured value (PV)
16-bit binary
Data register number storing a parameter
16-bit binary
Data register number storing the output value (MV)
16-bit binary
Oper-
and
Type
Bit Devices
Word Devices
Others
System User
Digit Specification
System User
Special
Unit
Index
Con-
stant
Real
Number
Charac-
ter String
Pointer
X Y M T C S D
.b KnX KnY KnM KnS
T
C
D
R U
\G
V
Z Modify K
H
E
"
"
P
3 3
3
3 3
3
3 3
3 3
3
FNC 88
PID
−
Mnemonic
Operation Condition
16-bit Instruction
9 steps
PID
Mnemonic
Operation Condition
Continuous
Operation
32-bit Instruction
S
1
S
1
S
1
S
2
S
3
S
1
D
S
1
S
1
S
1
S
2
S
2
S
3
S
1
D
S
1
S
2
S
3
S
3
D
S
3
Command
input
FNC 88
PID
S
3
S
2
S
1
D
Target value (SV)
Measured value (PV)
Parameter
Output value (MV)
