Mitsubishi Q Mode, Руководство по программированию

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MELSEC-Q/QnA
5. PID CONTROL PROCEDURE
(c) For QnACPU
Table 5.3 PID Control Data List
Data
No.
Data Item Description
Setting Range
User Specifi-
cation Range
Processing when Set Data is
Outside the Allowable Setting
Range
1
Number of
loops Sets the number of loops for which PID
operation will be executed.
1 to 32 1 to 32
Commo
n setting
data
2
Number of
loops in one
scan
Sets the number of loops for which single
PID operation will be executed when the
multiple loops reaches the sampling cycle
time.
1 to 32 1 to 32
An error occurs and PID
operation is not executed for all
loops.
1
Selection of
operational
expression
Selects the PID operational expression
indicated in Section 3.2.2.
Forward
operation: 0
Reverse
operation: 1
0 or 1
2
Sampling
cycle (T
S
)
Sets the cycle of PID operation. 0.01 to 60.00 s
1 to 6000
(unit: 10 ms)
3
Proportional
constant (K
P
)
PID operation ratio 0.01 to 100.00
1 to 10000
(unit: 0.01)
An error occurs and PID
operation for the corresponding
loop is not executed.
0.1 to 3000.0 s
4
Integral
constant (T
I
)
This constant expresses the magnitude of
the integral operation (I operation) effect.
Increasing the integral constant slows
down the manipulated value change.
Infinite( )
If the setting
for T
I
exceeds
3000.0 s
1 to 32767
(unit: 100 ms)
An error occurs and PID
operation for the corresponding
loop is not executed.
5
Derivative
constant (T
D
)
This constant expresses the magnitude of the
derivative operation (D operation) effect.
Increasing the derivative constant causes a
significant change in the manipulated value
even with slight change of the control objective.
0.00 to 300.00 s
0 to 30000
(unit: 10 ms)
6
Filter
coefficient
( )
Sets the degree of filtering applied to the
process value.
The filtering effect decreases as the value
gets closer to 0.
0 to 100 % 0 to 100
An error occurs and PID
operation for the corresponding
loop is not executed.
7
MV Lower
limit (MVLL)
In the automatic mode, sets the lower
limit for the MV (manipulated value)
calculated in PID operation.
When the MV is less than the MV lower
limit, the MVLL is used as the MV.
-50 to 2050 -50 to 2050
8
MV Upper
limit (MVHL)
In the automatic mode, sets the upper limit
for the MV calculated in PID operation.
When the MV is greater than the MV
upper limit, the MVHL is used as the MV.
-50 to 2050 -50 to 2050
PID operation is performed after
conversion into the following value.
When the MVLL or MVHL
value is less than -50, it is
converted into -50.
When the MVLL or MVHL
value is greater than 2050, it
is converted into 2050.
9
MV change
rate limit
( MVL)
Sets the limit for variation between the
previous MV and present MV.
When the MV variation is greater than
the limit value, 1 is set for bit 1 (b1) of the
alarm device.
Does not limit the MV variation.
(If the MV variation is greater than the
limit value, it is used unchanged as the
MV variation to calculate the MV.)
0 to 2000 0 to 2000
PID operation is performed after
conversion into the following
value.
When the MVL value is less
than 0, it is converted into 0.
When the MVL value is
greater than 2000, it is
converted into 2000.
Data for
each
loop
10
PV change
rate limit
( PVL)
Sets the limit for variation between the
previous PV and present PV.
When the PV variation is greater than
the limit value, 1 is set for bit 0 (b0) of the
alarm device.
Does not limit the PV variation.
(If the PV variation is greater than the limit
value, it is used unchanged as the PV
variation to perform the PID operation.)
0 to 2000 0 to 2000
PID operation is performed after
conversion into the following
value.
When the PVL value is less
than 0, it is converted into 0.
When the PVL value is
greater than 2000, it is
converted into 2000.