Pid Control (Pr. 88 To Pr. 94 ) - Mitsubishi FR-S500 Instruction Manual

2.10.10 PID control (Pr. 88
The inverter can be used to exercise process control, e.g. flow rate, air volume
or pressure.
The voltage input signal (0 to +5V or 0 to +10V) or Pr. 93 setting is used as a
set point and the 4 to 20mADC current input signal used as a feedback value
to constitute a feedback system for PID control.
POINT
Made valid by turning on the X14 signal. Use Pr. 60 to Pr. 63 (input terminal function
selection) to make assignment.
Parameter
88 PID action selection
89 PID proportional band
90 PID integral time
91 PID upper limit
92 PID lower limit
PID action set point for PU
93
operation
94 PID differential time
<Setting>
(1) Basic PID control configuration
Pr. 93 or Treminal 2
Set point
Kp: Proportion constant
(2) PID action overview
1) PI action
A combination of proportional control
action (P) and integral control action (I)
for providing a manipulated variable in
response to deviation and changes
with time.
REMARKS
PI action is the sum of P and I actions.
Factory
Name
Setting
20
100%
1s
- - -
- - -
0%
- - -
Inverter circuit :
+ -
Terminal 4
Feedback signal (Measured value)
Ti: Integral time
Operation selection function parameters
to Pr. 94 )
Setting Range
20, 21
0.1 to 999%, - - -
0.1 to 999s, - - -
0 to 100%, - - -
0 to 100%, - - -
0 to 100%
0.01 to 10s, - - -
PID operation
1
Kp 1+
+Td S
Ti S
S: Operator Td: Differential time
[Operation example for stepped
changes of measured value]
Deviation Set point
P action
I action
PI action
113
Remarks
Setting is enabled
when Pr. 30 = "1"
Motor
Manipulated
IM
variable
Measured value
Time
Time
Time
2