6.2.1 Pidinit Instruction - Mitsubishi MELSEC-L series Programming Manual

PIDINIT
Device Data item
MV lower limit
+8
s
(MVLL)
MV upper limit
+9
s
(MVHL)
MV change rate
limit
+10
s
( MVL)
PV change rate
limit
+11
s
( PVL)
6.2 PID Control Instruction (Exact Differential)
6-18

6.2.1 PIDINIT instruction

Description
With PID limits
Set the lower limit for the
manipulated value (MV)
calculated in PID
operation in automatic
-50 to 2050
mode.
If the MV is less than the
set lower limit value
(MVLL), the value is
clipped to the MVLL.
Set the upper limit for the
manipulated value
calculated in PID
operation in automatic
-50 to 2050
mode.
If the MV is greater than
the set upper limit value
(MVHL), the value is
clipped to the MVHL.
Set the variation limit
between the previous
MV and the present MV.
When the MV variation is
greater than the limit
value, bit 1 (b1) of the
0 to 2000
alarm device is set to '1'.
MV variation is not
limited. (Even if the MV
variation exceeds the
limit value, the actual MV
variation is used as it is
for calculating the MV.)
Set the variation limit
between the previous PV
and the present PV.
When the PV variation is
greater than the limit
value, bit 1 (b1) of the
alarm device is set to '1'.
0 to 2000
PV variation is not
limited. (Even if the PV
variation exceeds the
limit value, the actual PV
variation is used as it is
for performing the PID
operation.)
Setting range
Setting
Without PID
side
limits
-32768 to
User
32767
-32768 to
User
32767
-32768 to
User
32767
-32768 to
User
32767
Processing when the
setting data are outside the
setting range
In the case of "With PID
limits", the PID operation is
performed after values are
replaced as follows:
• If MVLL or MVHL value is
less than -50,
the value is
clipped to -50.
• If MVLL or MVHL value is
greater than 2050,
the
2050.
value is clipped to
In the case of "With PID
limits", the PID operation is
performed after values are
replaced as follows:
• If the MVL value is
less than 0, the value is
clipped to 0.
• If the MVL value is
greater than 2000,
the
2000.
value is clipped to
In the case of "With PID
limits", the PID operation is
performed after values are
replaced as follows:
• If the PVL value is
less than 0,
the value is
0.
clipped to
• If the PVL value is
greater than 2000,
the
2000.
value is clipped to