Operating instructions

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.
3-41 Ramp 1 Ramp Up Time
Range: Function:
Application
dependent
*
[Applica-
tion
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 =
t acc × n norm par .1 − 25
ref rpm
s
3-42 Ramp 1 Ramp Down Time
Range: Function:
Application
depend-
ent
*
[Applica-
tion
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 =
t dec × n norm par .1 − 25
ref rpm
s
3-45 Ramp 1 S-ramp Ratio at Accel. Start
Range: Function:
50 % * [Application
dependant]
Enter the proportion of the total ramp-up
time (par. 3-41 Ramp 1 Ramp up Time) in
which the acceleration torque increases.
The larger the percentage value, the
greater the jerk compensation achieved,
and thus the lower the torque jerks
occurring in the application.
3-46 Ramp 1 S-ramp Ratio at Accel. End
Range: Function:
50 % * [Application
dependant]
Enter the proportion of the total ramp-up
time (par. 3-41 Ramp 1 Ramp up Time) in
which the acceleration torque decreases.
The larger the percentage value, the
greater the jerk compensation achieved,
and thus the lower the torque jerks in the
application.
3-47 Ramp 1 S-ramp Ratio at Decel. Start
Range: Function:
50 % * [Application
dependant]
Enter the proportion of the total ramp-
down time (par. 3-42 Ramp 1 Ramp Down
Time) where the deceleration torque
increases. The larger the percentage value,
the greater the jerk compensation
achieved, and thus the lower the torque
jerks in the application.
3-48 Ramp 1 S-ramp Ratio at Decel. End
Range: Function:
50 % * [Application
dependant]
Enter the proportion of the total ramp-
down time (par. 3-42 Ramp 1 Ramp Down
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.
3.5.4 3-5* Ramp 2
Choosing ramp parameters, see 3-4*.
3-51 Ramp 2 Ramp Up Time
Range: Function:
Applica-
tion
depend-
ent
*
[Applica-
tion
depend-
ant]
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. 3-52 Ramp 2 Ramp Down Time.
par . 3 − 51 =
tacc × nnorm par . 1 − 25
ref rpm
s
3-52 Ramp 2 Ramp Down Time
Range: Function:
Applica-
tion
depend-
ent
*
[Applica-
tion
depend-
ant]
Enter the ramp-down time, i.e. the decelera-
tion 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. 3-51 Ramp 2 Ramp Up Time.
par .3 − 52 =
tdec × nnorm par . 1 − 25
ref rpm
s
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CA.02 - VLT
®
is a registered Danfoss trademark 51
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