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6 PID CONTROL INSTRUCTION
6.1 PID Control Instruction (Inexact Differential)
Setting data
Device
Data item
Description
Setting range
Setting
side
Processing when the
setting data are outside
the setting range
With PID limits
Without PID
limits
Common setting data (device: (s)+0 to (s)+1)
(s)+0
Number of loops
Set the number of loops for
PID operation.
1 to 32
User
An error occurs and the PID
operation for all loops is not
performed.
(s)+1
Number of loops in
one scan
Set the number of loops for
PID operation in one scan if
multiple loops have reached
the sampling cycle time.
1 to 32
User
Setting data for No. 1 loop (device: (s)+2 to (s)+15)
(s)+2
Operational
expression
selection
Select the PID operational
expression.
0: Forward
operation
1: Reverse
operation
0: Forward
operation
1: Reverse
operation
User
An error occurs and the PID
operation for the
corresponding loop is not
performed.
(s)+3
Sampling cycle
(T
S
)
Set the PID operation cycle.
1 to 6000
(unit: 10ms)
1 to 6000
(unit: 10ms)
User
(s)+4
Proportional
constant (K
P
)
Proportional gain of PID
operation
1 to 10000
(unit: 0.01)
1 to 10000
(unit: 0.01)
User
(s)+5
Integral constant
(T
I
)
Constant that expresses the
magnitude of the integral
action (I action) effect.
Increasing the integral
constant slows down the
manipulated value change.
1 to 32767
(unit: 100ms)
If setting value
> 30000
T
I
= Infinite (
)
1 to 32767
(unit: 100ms)
If setting value
> 30000
T
I
= Infinite (
)
User
(s)+6
Derivative constant
(T
D
)
Constant that expresses the
magnitude of the derivative
action (D action) effect.
Increasing the derivative
constant causes a significant
change in the manipulated
value even with a slight
change of the control target.
0 to 30000
(unit: 10ms)
0 to 30000
(unit: 10ms)
User
(s)+7
Filter coefficient (
)
Set the degree of filtering to
be applied to the process
value.
The filtering effect decreases
as the value gets closer to 0.
0 to 100
0 to 100
User
(s)+8
MV lower limit
(MVLL)
Set the lower limit for the
manipulated value (MV)
calculated in PID operation in
automatic mode.
If the MV is less than the set
lower limit value (MVLL), the
value is clipped to the MVLL.
-50 to 2050
-32768 to 32767
User
In the case of "With PID
limits", the PID operation is
performed after values are
replaced as follows:
• If the MVLL or MVHL is
less than -50, the value is
clipped to -50.
• If the MVLL or MVHL is
greater than 2050, the
value is clipped to 2050.
(s)+9
MV upper limit
(MVHL)
Set the upper limit for the
manipulated value calculated
in PID operation in automatic
mode.
If the MV is greater than the
set upper limit value (MVHL),
the value is clipped to the
MVHL.
-50 to 2050
-32768 to 32767
User
Summary of Contents for MELSEC System Q
Page 1: ...MELSEC Q L Structured Programming Manual Special Instructions ...
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Page 307: ...10 SFC CONTROL INSTRUCTION 10 2 SFC Transition Condition Comment Read 305 10 MEMO ...
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