Mitsubishi Electric MELSEC-Q series Programming Manual page 47

Setting Data Data Item
data No.
Data for 7 MV Lower
each loop limit (MVLL)
8 MV Upper
limit (MVHL)
9 MV change
rate limit (
MVL)
10 PV change
rate limit (
PVL)
11 Derivative
gain (K )
D
Description Complete derivative
With PID limits
Setting
Range
In the automatic mode, -50 to 2050
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.
In the automatic mode, -50 to 2050
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.
Sets the limit for variation 0 to 2000
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.)
Sets the limit for variation 0 to 2000
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.)
Sets a time period 
(operation delay) for
derivative operation.
As the value is greater,
the time period
decreases and operation
becomes closer to
complete derivative.
Without PID limits
User Setting User
Specification Range Specification
Range Range
-50 to 2050 -32768 to -32768 to
32767 32767
-50 to 2050 -32768 to -32768 to
32767 32767
0 to 2000 -32768 to -32768 to
32767 32767
0 to 2000 -32768 to -32768 to
32767 32767
  
5 PID CONTROL PROCEDURE
Processing
when Set Data
is Outside the
Allowable
Setting Range
For the High
Performance
model QCPU "with
PID limits" or the
QnACPU, 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.
In the case of
"with PID limits",
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.
In the case of
"with PID limits",
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.
An error occurs
and PID operation
for the
corresponding
loop is not
executed.
45
5.1 PID Control Data
5