Danfoss VLT Midi Drive FC 280 Programming Manual page 49

Parameter Descriptions
3-71 Ramp 4 Ramp up Time
Range: Function:
during ramping. The value 0.00 corresponds
to 0.01 s in speed mode. See ramp-down
time in parameter 3-72 Ramp 4 Ramp Down
Time.
Par . 3 − 71 =
3-72 Ramp 4 Ramp Down Time
Range: Function:
Size [0.01 - Enter the ramp-down time, which is the
related 3600 s] deceleration time from the rated motor
*
speed n to 0 RPM. Select a ramp-down time
s
such that no overvoltage 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
parameter 4-18 Current Limit. The value 0.00
corresponds to 0.01 s in speed mode. See
ramp-up time in parameter 3-71 Ramp 4
Ramp up Time.
Par . 3 − 72 =
3-80 Jog Ramp Time
Range: Function:
Size [0.01 Enter the jog ramp time, which is the
related - 3600 acceleration/deceleration time between 0 RPM
*
s] and the rated motor frequency n
the resulting output current required for the
given jog ramp time does not exceed the
current limit in parameter 4-18 Current Limit.
The jog ramp time starts when activating a
jog signal via the LCP, a selected digital
output, or the serial communication port.
When jog state is disabled, the normal
ramping times are valid.
Hz
P 4-14 Hz
high limit
P 1-25
Motor speed
P 3-19
Jog speed
P 4-12 Hz
low limit
t jog
P 3-80
Ramp up
(acc)
Illustration 4.6 Jog Ramp Time
t s x n
jog
Par . 3 − 80 =
Δ jog speed par . 3 − 19 RPM
MG07C302
Programming Guide
t s x n RPM
acc s
ref RPM
t s x n RPM
dec s
ref RPM
. Ensure that
s
t jog Time
P 3-80
Ramp down
(dec)
RPM
s
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3-81 Quick Stop Ramp Time
Range: Function:
Size [0.01 - Enter the quick-stop ramp-down time,
related 3600 s] which is the deceleration time from the
*
synchronous motor speed to 0 RPM. Ensure
that no resulting overvoltage occurs in the
inverter due to regenerative operation of
the motor required to achieve the given
ramp-down time. Also, ensure that the
generated current required to achieve the
given ramp-down time does not exceed
the current limit (set in
parameter 4-18 Current Limit). Activate quick
stop with a signal on a selected digital
input, or via the serial communication port.
Hz
P 4-14 Hz
high limit
Reference
P 1-25
Motor speed
P 4-12 Hz
low limit
Illustration 4.7 Quick Stop Ramp Time
3-90 Step Size
Range: Function:
0.10 % [0.01 - Enter the increment size required for
200 %] increase/decrease, as a percentage of the
*
synchronous motor speed, n
decrease is activated, the resulting reference
is increased/decreased by the amount set in
this parameter.
3-92 Power Restore
Option: Function:
[0] Off Reset the digital potentiometer reference to 0% after
*
power-up.
[1] On Restore the most recent digital potentiometer
reference at power-up.
4
Time
P 3-81
Qramp
Qstop
. If increase/
s
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