Mitsubishi MELSEC-Q series Programming Manual page 137

(2) Tracking processing
(a) The set value (SV) is converted reversely from the engineering value with the following operation expression to
calculate SVn'.
100
SV ' (SV
n
RH RL
(b) When all of the following conditions hold, tracking processing is performed.
1) The tracking bit (TRK) of the operation constant is 1.
2) The set value (E2) is used.
3) The operation mode (MODE) is any of MAN, AUT, CMV, CMB, CAB, LCM, LCA and LCC.
E2 = SVn'
(c) When the set value (E2) is the manipulated value (MV) of the upper loop, the tracking flag (TRKF) of the alarm
detection inhibition (INH) in the upper loop turns to 1.
(3) Gain (Kp) operation processing
(a) The deviation (DV) is calculated under the following condition.
Condition
Forward operation (PN = 1)
Reverse operation (PN = 0)
(b) The output gain (K) is calculated under the following condition.
Condition
When |DV|  GW
When |DV| > GW
(4) BPI operation
BPI operation is performed with the following operation expression.
Condition
BW ( MV)
Kp: K × Gain (P), BT: Execution cycle, T
DV : Cumulative value of DVn, DVn: Deviation
I
In the following case, however, note that special processing will be performed.
Condition
In either of the following cases 1, 2
1. Integral constant (I) = 0 (T
2. Either MLA or MHA of alarm
detection (ALM) is 1
1. Integral constant (I)
RL)
n
Operation expression
DV = E1 - SVn'
DV = SVn' - E1
Operation expression
K = GG
(1 GG) GW
K 1
|DV|
CT
K BW (DV
P n
: Integral constant (I),
I
= 0)
CT
I
DV last value unchanged
I
T
I
CT CT
0 (T 0) DV
I
I
T T
I
Operation expression
DV )
I
T
I
Processing
( DV DV )
I n
I
S.BPI
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4
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