3-58 Ramp 2 S-ramp Ratio at Decel. End
Range:
Function:
50 %
*
[Application
dependant]
Enter the proportion of the total ramp-
down time (
) where the deceleration torque
decreases. The larger the percentage
value, the greater the jerk compen-
sation achieved, and thus the lower the
torque jerks in the application.
3.5.5 3-6* Ramp 3
Configure ramp parameters, see 3-4*.
3-60 Ramp 3 Type
Option:
Function:
Select the ramp type, depending on
requirements for acceleration and
deceleration. A linear ramp will give constant
acceleration during ramping. An S-ramp will
give non-linear acceleration, compensating for
jerk in the application.
[0]
*
Linear
[1]
S-ramp
Const Jerk
Accelerates with lowest possible jerk.
[2]
S-ramp
Const Time
S-ramp based on the values set in
NOTE!
If S-ramp [1] is selected and the reference during ramping is
changed, the ramp time may be prolonged in order to
realize a jerk-free movement, which may result in a longer
start or stop time.
Additional adjustment of the S-ramp ratios or switching
initiators may be necessary.
3-61 Ramp 3 Ramp-up Time
Range:
Function:
Application
dependent
*
[Application
dependant]
Enter the ramp-up time, i.e., the
acceleration time from 0 RPM to
the rated motor speed n
s
. Choose
a ramp-up time such that the
output current does not exceed
the current limit in
during ramping. The value
0.00 corresponds to 0.01 sec. in
speed mode. See ramp-down time
in
.
3-62 Ramp 3 Ramp-down Time
Range:
Function:
Application
dependent
*
[Application
dependant]
Enter the ramp-down time, i.e., the
deceleration time from the rated
motor speed n
s
to 0 RPM. Choose a
ramp-down time such that no
overvoltage arises in the inverter due
to regenerative operation of the
motor, and such that the generated
current does not exceed the current
limit set in
. The
value 0.00 corresponds to 0.01 s in
speed mode. See ramp-up time in
Par. 3
−
62 =
tdec s x ns RPM
ref RPM
3-65 Ramp 3 S-ramp Ratio at Accel. Start
Range:
Function:
50 %
*
[Application
dependant]
Enter the proportion of the total ramp-
up time (
) in
which the acceleration torque
increases. The larger the percentage
value, the greater the jerk compen-
sation achieved, and thus the lower the
torque jerks in the application.
3-66 Ramp 3 S-ramp Ratio at Accel. End
Range:
Function:
50 %
*
[Application
dependant]
Enter the proportion of the total ramp-
up time (
) in
which the acceleration torque
decreases. The larger the percentage
value, the greater the jerk compen-
sation achieved, and thus the lower the
torque jerks in the application.
3-67 Ramp 3 S-ramp Ratio at Decel. Start
Range:
Function:
50 %
*
[Application
dependant]
Enter the proportion of the total ramp-
down time (
) where the deceleration torque
increases. The larger the percentage
value, the greater the jerk compen-
sation achieved, and thus the lower the
torque jerks in the application.
Parameter Descriptions
FC 300 Programming Guide
3-38
MG.33.MA.22 - VLT
®
is a registered Danfoss trademark
3
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