Mitsubishi Electric FR-A700 Instruction Manual page 669

Parameter
Pr. No. Name
PID control auto-
127
matic switchover
frequency
PID action
128
selection
PID proportional
129
band
130
PID integral time
131
PID upper limit
FR-A700 EC
Initial Setting
Description
Value Range
Set the frequency at which the control is
0–400Hz
automatically changed to PID control.
9999
Without PID automatic switchover
9999
function
PID reverse
10
action
PID forward
11
action
PID reverse
20
action
PID forward
21
action
PID reverse
50
action
PID forward
51
action
PID reverse
60
action
PID forward
61
action
10
PID reverse
70
action
PID forward
71
action
PID reverse
80
action
PID forward
81
action
PID reverse
90
action
PID forward
91
action
PID reverse
100
action
PID forward
101
action
If the proportional band is narrow
(parameter setting is small), the manip-
ulated variable varies greatly with a
slight change of the measured value.
0.1–1000% Hence, as the proportional band nar-
100%
rows, the response sensitivity (gain)
improves but the stability deteriorates,
e.g. hunting occurs.
Gain Kp = 1/proportional band
9999 No proportional control
For deviation step input, time (Ti)
required for only the integral (I) action to
provide the same manipulated variable
0.1–3600s as that for the proportional (P) action.
1s
As the integral time decreases, the set
point is reached earlier but hunting
occurs more easily.
9999 No integral control.
Set the upper limit value. If the feedback
value exceeds the setting, the FUP signal
0–100% is output. The maximum input (20mA/
9999
5V/10V) of the measured value (terminal
4) is equivalent to 100%.
9999 No function
Parameters referred to
Output signal of an
178–189
external PID control-
ler: terminal 1
190–196
Measured value
(terminal 4 )
C2 (Pr. 902)
Set point (terminal 2
C7 (Pr. 905)
or Pr. 133)
Deviation value signal
input
(LONWORKS , CC-
Link communication)
Measured value, set
point input
(LONWORKS , CC-
Link communication)
Deviation value signal
input (PLC function)
Measured value, set
point input
(PLC function)
Deviation value signal
input (PLC function)
(Not reflected to the
inverter frequency)
Measured value, set
point input (PLC
function) (Not
reflected to the
inverter frequency)
Special operation
Refer to
Section
59 Remote function 6.10.4
selection
73 Analog input 6.20.2
selection
79 Operation mode 6.22.1
selection
Input terminal
6.14.1
function selection
Output terminal
6.14.5
function selection
Frequency 6.20.5
– setting voltage
(current) bias/
gain
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