INVT Goodrive350-19 Series Operation Manual page 239

Goodrive350-19 series VFD for crane
Function
Name
code
Torque boost of
P04.01
motor 1
Torque boost
P04.02
cut-off of motor 1
Description
4: Torque-down V/F curve (power of 2.0)
Curves 2 – 4 are applicable to the torque loads
such as fans and water pumps. You can adjust
according to the characteristics of the loads to
achieve best performance.
5: Customized V/F (V/F separation); in this
mode, V can be separated from F and F can be
adjusted through the frequency setting channel
set by P00.06 or the voltage setting channel set
by P04.27 to change the characteristics of the
curve.
Note: In the following figure, V
rated voltage and f
b
frequency.
Output voltage
V
b
Straight-type
Square-type
In order to compensate for low-frequency torque
characteristics, you can make some boost
compensation for the output voltage.
relative to the max. output voltage V
P04.02 defines the percentage of cut-off
frequency of manual torque boost to the rated
motor frequency f . Torque boost can improve
b
the low-frequency torque characteristics of V/F.
You need to select torque boost based on the
load. For example, larger load requires larger
torque boost, however, if the torque boost is too
large, the motor will run at over-excitation, which
may cause increased output current and motor
overheating, thus decreasing the efficiency.
When torque boost is set to 0.0%, the VFD uses
automatic torque boost.
Torque boost cut-off threshold: Below this
-227-
is the motor
b
is the motor rated
Torque -down V/F curve (power of 1.3)
Torque -down V/F curve (power of 1.7)
Torque -down V/F curve (power of 2.0)
Output frequency
f
b
P04.01
.
b
Function parameter list
Default Modify
○
0.0%
is
○
20.0%