Toshiba VF-nC1 - Manual (Page 82)

E6581090
F-18
6
4) Adjusting the PI control gain level
Adjust the PI control gain level according to the process quantity, the feedback signal and the object
to be controlled.
The following parameters are provided for gain adjustment.
Parameter Adjustment range Default setting
H (P gain) 0.01～100.0 0.30
H (I gain) 0.01～100.0 0.20
H (Proportional (P) gain adjustment parameter)
This parameter is used to adjust the proportional gain level during PI control. A correction factor,
which is proportional to the particular deviation (the difference between the set frequency and the
feedback value), is obtained by multiplying this deviation by the parameter setting.
Increasing the P gain increases response. However, increasing it higher than required results in an
undesirable event such as hunting.
Slow response
Process quantity
setting
Time
Fast response
H (Integral (I) gain adjustment parameter)
This parameter is used to adjust the integral gain level during PI control. Any deviations remaining
after proportional control are cleared to zero (residual deviation offset function).
Increasing the I gain increases response. However, increasing it higher than required results in an
undesirable event such as hunting.
Residual deviation
Process quantity setting
Time
5) Adjusting an analog command voltage
To use feedback input (VI/S3 terminal), perform a voltage-scaling adjustment as required. See
Section 6.4.1 for details.
If the feedback input value is very small, the voltage-scaling adjustment value can also be used for
gain adjustment.
Example of voltage signal setting Example of current signal setting
H
(80Hz)
H
(0Hz)
0V
H
0%
10V
H
100%
H
(80Hz)
H
(0Hz) 4mA
H
20%
20mA
H
100%