Mitsubishi Electric FR-A700 Series, Техническое руководство

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402
PARAMETER
2.20.4 PID control [Pr. 127 to 134, 575 to 577*]
(common)
The inverter can be used to exercise process control, e.g.
flow rate, air volume or pressure.
The terminal 2 input signal or parameter setting is used as
a set point and the terminal 4 input signal used as a feedback value to constitute a feedback system for PID
control.
common
(*[Pr. 575 to 577] are not available for .)
E700
[Pr.] Name
Initial
Value Setting
Range
Description
Available
Inverters
127
PID control
automatic
switchover
frequency
9999
0 to 400Hz
Set the frequency at which the control is automatically changed to
PID control.
{ { {
9999 Without PID automatic switchover function
128
PID action
selection
10
0
0 PID action is not performed —
{ {
10 PID reverse action Deviation value signal input
(terminal 1 )
{
— —
11 PID forward action
20 PID reverse action Measured value (terminal 4)
Set value (terminal 2 or [ Pr. 133 ])
{ { {
21 PID forward action
40 PID reverse action
Addition
method: fixed
For dancer control
set point
( [ Pr. 133 ] ) ,
measured value (terminal 4),
main speed (frequency
command of the operation
mode)(
Refer to page 411 )
—
{ {
41 PID forward action
42 PID reverse action
Addition
method: ratio
43 PID forward action
50 PID reverse action Deviation value signal input
(L
ON
W
ORKS
, CC-Link communication)
{ {
—
51 PID forward action
60 PID reverse action Measured value and set point input
(L
ON
W
ORKS
, CC-Link communication) 61 PID forward action
129
*1
PID
proportional
band
100%
0.1 to 1000%
If the proportional band is narrow (parameter setting is small), the
manipulated variable varies greatly with a slight change of the
measured value. Hence, as the proportional band narrows, the
response sensitivity (gain) improves but the stability deteriorates,
e.g. hunting occurs. Gain Kp = 1/proportional band
{ { {
9999 No proportional control
130
*1
PID integral
time
1s
0.1 to 3600s
For deviation step input, time (Ti) required for only the integral (I)
action to provide the same manipulated variable as that for the
proportional (P) action. As the integral time decreases, the set
point is reached earlier but hunting occurs more easily.
{ { {
9999 No integral control.
131 PID upper limit 9999
0 to 100%
Set the upper limit value. If the feedback value exceeds the
setting, the FUP signal is output. The maximum input (20mA/5V/
10V) of the measured value (terminal 4) is equivalent to 100%.
{ { {
9999 No function
132 PID lower limit 9999
0 to 100%
Set the lower limit value. If the measured value falls below the
setting range, the FDN signal is output. The maximum input
(20mA/5V/10V) of the measured value (terminal 4) is equivalent to
100%.
{ { {
9999 No function
133
*1
PID action set
point
9999
0 to 100% Used to set the set point for PID control.
{ { {
9999 Terminal 2 input is the set point.
134 *1
PID differential
time
9999
0.01 to 10.00s
For deviation ramp input, time (Td) required for providing the
manipulated variable for the proportional (P) action only. As the
differential time increases, greater response is made to a deviation
change.
{ { {
9999 No differential control.
A700
F700
E700 D700
A700
F700
E700
D700