Mitsubishi Electric MELSEC-FX3S Series - How to Use PID Instruction; Explanation of Function and Operation

FX 3S /FX 3G /FX 3GC /FX 3U /FX 3UC PLC User's Manual - Analog Control Edition
PID Instruction (FNC 88)
M-5
2 How to Use PID Instruction
2.1 Explanation of function and operation
K
FX
3U
-4AD-PNK
-ADP
L
FX
3U
-4AD-TC
-ADP
M
PID Instruction (FNC 88)
2. How to Use PID Instruction
1. Instruction format
2. Set data
3. Target devices
1 : Only available for FX3G/FX3GC/FX3U/FX3UC PLCs.
2 : Only available for FX3U/FX3UC PLCs.
2.1 Explanation of function and operation
1. 16-bit PID operation
Once the target value , measured value and PID parameters to + 6 are set and the
program is executed, the operation result (MV) is transferred to the output value at every sampling
time. The sampling time is specified by
Operand type Description Data type
Data register storing the target value (SV)
Binary 16-bit
Data register storing the measured value (PV)
Binary 16-bit
Data register storing PID parameters
Binary 16-bit
Data register storing the output value (MV)
Binary 16-bit
Operand
type
Bit devices Word devices Others
System User Digit Specification System User
Special
Unit
Index
Con-
stant
Real
Num-
ber
Char-
acter
String
Poin-
ter
XYMTCSD.b KnX KnY KnM KnS T C D R U\G VZ
Mod-
ify
KH E ""P
 1 2
 1 2
 1
 1 2
32-bit
Instruction
⎯
Mnemonic Operation Condition
FNC 88
PID
PID
16-bit
Instruction
9 steps PID
Continuous
Operation
Mnemonic Operation Condition
S 1
S 2
S 3
D
S 1
S 2
S 3
D
S 1
S 2
S 3
S 3
D
S 3
Command
input
FNC 88
PID
S3S2S1 D
Target
value
(SV)
Measured
value
(PV)
PID
Parameters
Output
value
(MV)