Toshiba G3 Workbook page 51

there can be some oscillations that (hopefully) settle out after a time called the Settling Time. Remember
that as the output frequency changes, so does the pressure. THE USER MUST DECIDE WHAT ARE
The rise time, settling time, and overshoot are dependent on the system and can be adjusted by changing
three of the parameters in the table programming above: Proportional Gain, Integral Time, and Derivative
Process Variable
Flow
Levels: fast
Levels: slow
Pressure: fast
Pressure: slow
Temperature: fast
Temperature: slow
Temperature: furnace
Compressor speed
Setpoint
(frequency
command that
develops
desired
process
condition)
For additional assistance, please contact Toshiba Adjustable Speed Drive Marketing Dept. at (800) 872-
ACCEPTABLE RISE AND SETTLING TIMES.
Some recommended PID values based on application type:
Proportional
Gain
0.3
1.0
0.25
2.0
1.0
1.0
1.0
0.8
1.0
Simplified PID flowchart
Proportional
(+) Integral
error
(-)
Differential
Feedback (indicates actual process
condition)
V
error
Time.
Integral Gain
(seconds/repeat)
0.6
8.0
16.0
0.5
2.0
2.0
16.0
8.0
2.0
+
+
+
= V - V
setpoint feedback
2192
Anti-Hunting Gain
(seconds)
0.0
0.0
0.0
0.0
0.0
0.0
0.25
0.125
0.0
new frequency reference to
drive main circuit
51