IMPULSE®•G+ & VG+ Series 4 Instruction Manual – February 2017
5-67
Hunting Prevention
Occasionally, in an application, resonance between the internal control system and the mechanical
system causes instability. This is called hunting, and may cause a crane to vibrate at a lower speed
(up to 30 Hz) and/or with a light load. The hunting prevention function monitors the motor flux and
uses a special control circuit to “smooth out” any peaks in the output current wave form.
Increase the set value of D11-02 when hunting is present while driving a light load. Decrease the set
value of D11-02 when the motor vibrates or stalls while driving a heavy load.
Table 5-53: Hunting Prevention Parameter Settings
Parameter Display Function Range Default
Control
Method
Model
D11-01 Hunt Prev Select Enable/Disable Hunt
Prevention function
0, 1 1 V/f G+
0 Disabled
1 Enabled
D11-02 Hunt Prev Gain Hunting Prevention Gain 0.00–2.50 1.00 V/f G+
D11-03 Hunt Prev Time Hunting Prevention Time
Constant
0–500ms 10 V/f G+
D11-05 Rev Hunt Prev Gn Reverse Hunting Prevention
Gain
0.00–2.50 0.00 V/f G+