Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 1239

■Gain (Kp) operation processing (3)
• The deviation (DV) is calculated under the following conditions.
Condition
Direct action (PN = 1)
Reserve action (PN = 0)
• The output gain (K) is calculated under the following conditions.
Condition
|DV|  GW
|DV| > GW
■PID operation (4)
The PID operation is performed with the following operational expression.
Item
B Direct action (PN = 1)
n
Reserve action (PN =
0)
BW(MV)
: K  Gain (P), M
K : Derivative gain (MTD), T
P D
Note that special processing is performed in the following cases.
Condition
In either of the following cases:
1. Derivative constant (D) = 0 (T = 0)
D
2. Control mode (MODE) = MAN, LCM, or CMV
In any of the following cases:
1. Integral constant (I) = 0 (T = 0)
I
2. MHA2 or MLA2 of alarm detection 2 (ALM2) is 1.
MVP>MH
and
CT
×DV >0
n
T
I
3. MHA2 or MLA2 of alarm detection 2 (ALM2) is 1.
MVP<ML
and
CT
×DV <0
n
T
I
■Deviation check (5)
A deviation is checked under the following conditions, and the result is output to the DVLA of the alarm detection (ALM) and
the large deviation alarm (BB1).
Condition
DVL < |DV|
(DVL - DVLS) < |DV|  DVL
|DV|  (DVL - DVLS)
*1 If the DMLI or ERRI of the disable alarm detection (INH) is set to 1, the DVLA of the alarm detection (ALM) and the large deviation alarm
(BB1) are set to 0.
Operational expression
DV = E1 - SV '
n
DV = SV ' - E1
n
Operational expression
K = GG
(1-GG)×GW
K=1-
|DV|
Operational expression
M ×T
D D
B + ×{(PV -2PV
n-1 n n-1
M ×CT+T
D D
M ×T
D D
B + ×{-(PV -2PV
n-1 n
M ×CT+T
D D
CT
K ×{(DV -DV )+ ×DV +B }
P n n-1 n n
T
I
: Integral constant (I), T
I
Result
*1
DVLA = BB1 = 1
DVLA = BB1 = Last value status hold
DVLA = BB1 = 0
CT×B
n-1
+PV )- }
n-2
T
D
CT×B
n-1
+PV )- }
n-1 n-2
T
D
: Derivative constant (D)
D
Processing
B = 0
n
(Note that the loop tag past value memory is set.)
CT
×DV =0
n
T
I
*1
11 PROCESS CONTROL INSTRUCTIONS
11.3 Control Operation Instructions
11
1237