Danfoss VLT AutomationDrive FC 300 Programming Manual page 78

FC 300 Programming Guide
If S-ramps are selected then set the level of non-linear jerk compensation required. Set jerk compensation by defining the proportion of ramp-up and
ramp-down times where acceleration and deceleration are variable (i.e. increasing or decreasing). The S-ramp acceleration and deceleration settings are
defined as a percentage of the actual ramp time.
3-40 Ramp 1 Type
Option:
[0] * Linear
[1] S-ramp Const Jerk
[2] S-ramp Const Time
NB!
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.
3-41 Ramp 1 Ramp up Time
Range:
Application [Application dependant]
dependent*
Function:
Select the ramp type, depending on requirements for acceleration/deceleration.
A linear ramp will give constant acceleration during ramping. An S-ramp will give non-linear accel-
eration, compensating for jerk in the application.
Acceleration with lowest possible jerk.
S-ramp based on the values set in par. 3-41
Down Time
.
Function:
Enter the ramp-up time, i.e. the acceleration time from 0 RPM to the synchronous motor speed n
Choose a ramp-up time such that the output current does not exceed the current limit in
par. 4-18 Current Limit during ramping. The value 0.00 corresponds to 0.01 sec. in speed mode.
See ramp-down time in par. 3-42 Ramp 1 Ramp Down Time
t acc s x n s RPM
Par
. 3 − 41 =
ref RPM
®
MG.33.M8.02 - VLT is a registered Danfoss trademark
3 Parameter descriptions
Ramp 1 Ramp up Time
and par. 3-42
.
3
Ramp 1 Ramp
.
S
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