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 over-
voltage 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 sec. 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-
3-66 Ramp 3 S-ramp Ratio at Accel. End
Range:
Function:
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.
3-68 Ramp 3 S-ramp Ratio at Decel. End
Range:
Function:
50 %
*
[Application
dependant]
Enter the proportion of the total ramp-
downdecel time (
) where the deceleration
torque decreases. The larger the
percentage value, the greater the jerk
compensation achieved, and thus the
lower the torque jerks in the
application.
3.5.6 3-7* Ramp 4
Configure ramp parameters, see 3-4*.
3-70 Ramp 4 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
and
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.
Parameter Descriptions
FC 300 Programming Guide
60
MG.33.MB.02 - VLT
®
is a registered Danfoss trademark
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