Danfoss FC 300 Programming Manual page 82

2. How to Programme
2.6.7. 3-7* Ramp 4
Configure ramp parameters, see 3-4*.
2
3-70 Ramp 4 Type
Option:
[0]
[1]
[2]
3-71 Ramp 4 Ramp up Time
Range:
Size re-
lated
3-72 Ramp 4 Ramp Down Time
Range:
Size re-
lated
3-75 Ramp 4 S-ramp Ratio at Accel. Start
Range:
50%
82
* Linear
S-ramp Const Jerk
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.
[0.01 - 3600.00 s]
[0.01 - 3600.00 s]
* [1 - 99%]
MG.33.M2.02 - VLT
Function:
Select the ramp type, depending on requirements for accelera-
tion and deceleration. A linear ramp will give constant acceler-
ation during ramping. An S-ramp will give non-linear accelera-
tion, compensating for jerk in the application
Accelerates with lowest possible jerk.
S-ramp based on the values set in par. 3-71 and 3-72.
Function:
Enter the ramp-up time, i.e. the acceleration time from 0 RPM
to the rated motor speed n
M,N
time such that the output current does not exceed the current
limit in par. 4-18 during ramping. The value 0.00 corresponds
to 0.01 sec. in speed mode. See ramp-down time in par. 3-72.
t s x n
acc
Par . 3 − 71 =
Function:
Enter the ramp-down time, i.e. the deceleration time from the
rated motor speed n (par. 1-25) to 0 RPM. Choose a ramp-
M,N
down time such that no over-voltage arises in the inverter due
to regenerative operation of the motor, and such that the gen-
erated current does not exceed the current limit set in par. 4-18.
The value 0.00 corresponds to 0.01 s in speed mode. See ramp-
up time in par. 3-71.
t s x n
dec
Par
. 3 − 72 =
Function:
Enter the proportion of the total ramp-up time (par. 3-71) in
which the acceleration torque increases. The larger the per-
centage value, the greater the jerk compensation achieved, and
thus the lower the torque jerks in the application.
®
is a registered Danfoss trademark
FC 300 Programming Guide
(par. 1-25). Choose a ramp-up
( . 1 − 25 )
par RPM
M N
,
ref RPM
Δ
( . 1 − 25 )
par RPM
M , N
ref RPM
Δ