Mitsubishi Electric FR-E800, Instruction Manual

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380
15. (A) Application Parameters
15.4 PID control
15.4
PID control
Process control such as flow rate, air volume or pressure are possible on the inverter.
A feedback system can be configured and PID control can be performed with the set point and feed back values set by analog
input signals (terminals 2 and 4) or using parameter values given via communication or by the PLC function.
Pr. Name Initial value Setting range Description
127
A612 PID control automatic
switchover frequency
9999
0 to 590 Hz
Set the value at which control is automatically switched to PID
control.
9999 No PID control automatic switchover function
128
A610
PID action selection 0
0, 20, 21, 50, 51,
60, 61, 1000,
1001, 1010,
1011, 2000,
2001, 2010, 2011
Select how to input the deviation value, measured value and set
point, and forward and reverse action.
40 to 43 Refer to page 396 .
129
A613
PID proportional band 100%
0.1% to 1000%
If a narrow proportional band is set (small parameter setting value),
the manipulated amount changes considerably by slight changes in
the measured value. As a result, response improves as the
proportional band becomes narrower, though stability worsens as
shown by the occurrence of hunting. Gain Kp=1/proportional band
9999 No proportional control
130
A614
PID integral time 1 s
0.1 to 3600 s
With deviation step input, this is the time (Ti) used for obtaining the
same manipulated amount as proportional band (P) by only integral
(I) action. Arrival to the set point becomes quicker the shorter an
integral time is set, though hunting is more likely to occur.
9999 No integral control
131
A601
PID upper limit 9999
0% to 100%
Set the upper limit. The FUP signal is output when the feedback
value exceeds this setting. The maximum input (20 mA/5 V/10 V) of
the measured value is equivalent to 100%.
9999 No function
132
A602
PID lower limit 9999
0% to 100%
Set the lower limit. The FDN signal is output when the measured
value falls below the setting range. The maximum input (20 mA/5 V/
10 V) of the measured value is equivalent to 100%.
9999 No function
133
A611
PID action set point 9999
0% to 100% Set the set point during PID control.
9999 Set point set by Pr.128 .
134
A615
PID differential time 9999
0.01 to 10 s
With deviation ramp input, this is the time (Td) used for obtaining the
manipulated amount only by proportional action (P). Response to
changes in deviation increase greatly as the differential time
increases.
9999 No differential control
553
A603
PID deviation limit 9999
0% to 100%
The Y48 signal is output when the absolute value of the deviation
exceeds the deviation limit value.
9999 No function
554
A604 PID signal operation
selection
0 0 to 3, 10 to 13
The action when the upper or lower limit for a measured value input
is detected or when a limit for the deviation is detected can be
selected. The operation for PID output suspension function can be
selected.
575
A621 Output interruption
detection time
1 s
0 to 3600 s
When the output frequency after PID calculation stays less than the
Pr.576 setting for the time set in Pr.575 or more, the inverter
operation is suspended.
9999 No output interruption function
576
A622 Output interruption
detection level
0 Hz 0 to 590 Hz Set the frequency at which output interruption is performed.
577
A623 Output interruption
cancel level
1000% 900% to 1100%
Level at which the PID output suspension function is released. Set
"
Pr.577 - 1000%".
609
A624 PID set point/deviation
input selection
2
2 The set point or deviation value is input through terminal 2.
3 The set point or deviation value is input through terminal 4.
4 The set point or deviation value is input via communication.
5 The set point or deviation value is input by the PLC function.