N700E INSTRUCTION MANUAL
3-27
A73
PID Feedback Type
0: “OI” Current Input (DC 4~20mA)
1: “O” Voltage Input (DC 0~10V)
Select the source how to enter the PID set point in A72.
Related Parameters: A70~A85
A74
PID P Gain
Range: 0.1 ~ 1000 % in 0.1 %
Select the PID P gain value
It sets the output rate of error between set point value and the feedback value
For faster response speed, enlarge the P gain value
If P gain is set too large, oscillation or over shooting may occur
Related Parameters: A70~A85
[Input method of target value signal and feedback signal]
Set the reference signal according to the PID reference setting method (A72).
Set the feedback signal according to the PID feedback source (A73)
If A73=0, input terminal being set [AT] has to be ON
.
A75
PID I Gain Time
Range: 0.0 ~ 3600 Sec in 0.1 Sec
Select the integral time to accumulate PID error value
For faster response speed, shorten the accumulate time
If I Gain time is set too short, oscillation or over shooting may occur
Related Parameters:
A76
PID D Gain Time
Range: 0.0 ~ 10.00 Sec in 0.01 Sec
Program the derivative time for PID function
For faster response speed, lengthen the D gain time
If D gain time is set too long, system may become unstable
Related Parameters:
PID Gain Adjustment Example
If the response is not stabilized in a PID control operation, adjust the gains as follows according to the
symptom
The change of controlled variable is slow even when the target value is changed.
Increase P gain [A74]
The change of controlled variable is fast, but not stable.
Decrease P gain[A74]
It is difficult to make the target value match with the controlled variable.
Decrease I time [A75]
Both the target value and the controlled variable are not stable.
Increase I time[A75]
The response is slow even when the P gain is increased.
Increase D time[A76]
The response is not stabilized due to oscillation even when the P gain is increased.
Decrease D time[A76]