3-40 Ramp 1 Type
Option: 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.
[0] * Linear
[1] S-ramp Const Jerk Acceleration with lowest possible jerk.
[2] S-ramp Const Time S-ramp based on the values set in par. 3-41
Ramp 1 Ramp up Time
and par. 3-42
Ramp 1 Ramp
Down 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: Function:
Application
dependent*
[Application dependant] Enter the ramp-up time, i.e. the acceleration time from 0 RPM to par. 1-25
Motor Nominal Speed
.
Choose a ramp-up time such that the output current does not exceed the current limit in
par. 4-18
Current Limit
during ramping. See ramp-down time in par. 3-42
Ramp 1 Ramp Down
Time
.
par
.3 − 41 =
tacc
×
nnorm
par
.1 − 25
ref
rpm
s
3-42 Ramp 1 Ramp Down Time
Range: Function:
Application
dependent*
[Application dependant] Enter the ramp-down time, i.e. the deceleration time from par. 1-25
Motor Nominal Speed
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 par. 4-18
Current Limit
. See ramp-up time in par. 3-41
Ramp 1 Ramp Up Time
.
par
.3 − 42 =
tdec
×
nnorm
par
.1 − 25
ref
rpm
s
VLT
®
HVAC Drive Programming Guide 3 Parameter Description
MG.11.C9.02 - VLT
®
is a registered Danfoss trademark
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