Toshiba TOSVERT VF-MB1 Instruction Manual page 181

4) Adjusting the PID control gain level
Adjust the PID control gain level according to the process quantities, the feedback signals and the object to
be controlled.
The following parameters are provided for gain adjustment:
Title Function
Proportional gain (P)
f362
Integral gain (I)
f363
Derivative gain (D)
f366
f362 (P-gain adjustment parameter)
This parameter adjusts the proportional gain level during PID control. A correction value proportional to
the particular deviation (the difference between the process value and the feedback value) is obtained
by multiplying this deviation by the parameter setting.
A larger P-gain adjustment value gives faster response. Too large an adjustment value, however,
results in an unstable event such as hunting.
Feedback value
Fast response
( = Large gain)
f363 (I-gain adjustment parameter)
This parameter adjusts the integral gain level during PID control. Any remaining deviations (residual
deviation offset) during proportional action are cleared to zero.
A larger I-gain adjustment value reduces residual deviations. Too large an adjustment value, however,
results in an unstable event such as hunting.
Feedback value
Assign an input terminal function 52 (PID integral/derivative) to an input terminal, when that input
terminal is ON, it is possible to calculate integral/derivative amounts always as 0 (zero).
Adjustment range
0.01 - 100.0
0.01 - 100.0
0.00 - 2.55
Slow response ( = Small gain)
( = Small gain)
Residual deviation
( = Large gain)
F-61
E6581697
Default setting
0.30
0.20
0.00
Process value
Time
Process value
Time
6