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Illustration 33: Example of Adaptive Control Start (Parameter 2-5 Adaptive Start Profile)
1
Early acceleration
2
Constant acceleration
3
Late acceleration
4
Parameter 2-2 Start Ramp Time
9.8.5.1 Fine-tuning Adaptive Control
If the motor does not start or stop smoothly, adjust
parameter 2-12 Adaptive Control Gain
. The gain setting determines how much
the soft starter adjusts future adaptive control starts and stops, based on information from the previous start. The gain setting af-
fects both starting and stopping performance.
If the motor accelerates or decelerates too quickly at the end of a start or stop, increase the gain setting by 5–10%.
If the motor speed fluctuates during starting or stopping, decrease the gain setting slightly.
N O T I C E
The soft starter tunes adaptive control to match the motor. Changing the following parameters resets adaptive control and the
first start/stop cycle uses constant current start/timed voltage ramp stop:
Parameter 1-2 Motor Full Load Current
,
parameter 2-4
Current Limit
, and
parameter 2-12 Adaptive Gain
.
9.9 Stop Methods
9.9.1 Coast to Stop
Coast to stop lets the motor slow at its natural rate with no control from the soft starter. The time required to stop depends on the
type of load.
9.9.2 Timed Voltage Ramp
Timed voltage ramp (TVR) reduces the voltage to the motor gradually over a defined time. This can extend the stopping time of the
motor and may avoid transients on generator set supplies.
N O T I C E
The load may continue to run after the stop ramp is complete.
AQ262141844215en-000401 / 175R1174
66 | Danfoss A/S © 2020.12
Operation
VLT® Soft Starter MCD 600
Operating Guide