gefran VDI100 Series Instruction Manual page 219

Fine-tuning PID control parameters:
(1) Reduce overshoot
Output
(2) Stabilize PID control
Output
(3) Reduce long-period oscillation
Output
(4) Reduce short-period oscillation
Output
Code Parameter Name / Range
10-11 PID feedback loss detection selection
0: Disable
1: Warning
2: Fault
10-12 PID feedback loss detection level
0~100 %
10-13 PID feedback loss detection time
0.0~10.0 s
The PID control function provides closed-loop system control. In case PID feedback is lost, the inverter output
frequency may be increase to the maximum output frequency.
It is recommended to enable to the PID feedback loss when the PID function is used.
PID feedback loss detection
10-11=0: Disable
10-11=1: Warning
A feedback loss condition is detected when the PID feedback value falls below the value set in parameter 10-12
(PID feedback loss detection level) for the time set in parameter 10-13 (PID feedback loss detection time). PID
VDI100 • Instruction manual
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In case overshoot occurs, reduce the derivative time (D) and increase
the integral time (I).
To quickly stabilize the PID control, reduce the integral time (I) and
increase the differential time (D) in case overshoot occurs.
Adjust the integral time (I) in case of long-periodical system oscillation.
Adjusting the differential time (D) and proportional (P) gain when experi-
encing short-periodical oscillation.
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