Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 154

• High/low limiter
High/low limiter processing result
Execution cycle (ΔT)
Control cycle (CT)
Condition
Variation rate limiter processing result
> MH
Variation rate limiter processing result
< ML
ML  Variation rate limiter processing
result  MH
MH: Output high limit value, ML: Output low limit value
■Reset windup
As countermeasures against reset windup, this function block sets a manipulated value to the high/low limit value when the
manipulated value has exceeded the limit value, and quickly responds to a control target when deviation is inverted.
Condition
Variation rate limiter processing result > MH and
Variation rate limiter processing result < ML and
MH: Output high limit value
ML: Output low limit value
MVP: MV internal operation value
T: Execution cycle
T: Tentative manipulated value
Ti: Integral time
However, when Ti is 0, countermeasure processing against reset windup is not performed.
■Output conversion
This function block performs output conversion processing.
Converted output (MVN)
NMAX
NMIN
(-10(%))
Converted output (MVN)={(NMAX-NMIN)×
NMAX: Output conversion high limit value
NMIN: Output conversion low limit value
MV: Manipulated variable (%)
MVN: Output conversion output value
9 I/O CONTROL
152
9.2 Output Processing-1 with Mode Switching (With Input Addition) (M+P_OUT1)
Variation rate limiter processing value
Control cycle (CT)
High/low limiter processing
result
MH
ML
Variation rate limiter processing value
ΔT ≤1
Ti
ΔT ≤1
Ti
0(%) 100(%)
MV
}+NMIN
100
Control cycle (CT)
Alarm (ALM)
Output low limit (MLA)
FALSE (Reset)
TRUE (Detected)
FALSE (Reset)
Countermeasure processing against reset windup
ΔT
MVP= ×(MH-T)+T
Ti
ΔT
MVP= ×(ML-T)+T
Ti
Manipulated
variable (MV)
(110(%))
High/low limiter
processing value
Output high limit
(MH)
Output low limit
(ML)
t
Output high limit (MHA)
TRUE (Detected)
FALSE (Reset)
FALSE (Reset)