Mitsubishi Electric 800 Series Instruction Manual page 400

 Basic configuration of PID control
• Pr.128 ="10, 11" (deviation value signal input)
Set point
To outside
*1 Set "0" to Pr.868 Terminal 1 function assignment. When Pr.868  "0", PID control is invalid.
• Pr.128 = "20, 21" (measured value input)
Pr.133 or
terminal 2 ∗2
Set point
0 to 5 VDC
(0 to 10 V, 4 to 20 mA)
*2 Note that the input of terminal 1 is added to the set point of terminal 2 as a set point.
Set "0" to Pr.858 Terminal 4 function assignment. When Pr.858  "0", PID control is invalid.
*3
 PID action outline
• PI action
PI action is a combination of proportional action (P) and integral action (I), and applies a manipulated amount according to the
size of the deviation and transition or changes over time.
[Example of action when the measured value changes in a stepped manner]
(Note) PI action is the result of P and I actions being added together.
Inverter circuit
PID operation
Deviation signal
+ -
Terminal 1 ∗1
1+
Kp
0 to 10 VDC
(0 to 5 V)
Feedback signal (measured value)
Kp: Proportionality constant Ti: Integral time S: Operator Td: Differential time
Inverter circuit
PID operation
+ -
1+
Kp
Terminal 4 ∗3
Feedback signal (measured value)
Kp: Proportionality constant Ti: Integral time S: Operator Td: Differential time
Deviation Set point
P action
I action
PI action
Motor
Manipulated
variable
1
+Td S
Ti S
Motor
Manipulated
variable
1
+Td S
Ti S
4 to 20 mADC (0 to 5 V, 0 to 10 V)
Measured value
Time
Time
Time
M
M
5. PARAMETERS
5.11 (A) Application parameters
3
4
5
5
5
6
7
8
9
10
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