Siemens SINAMICS G120 Original Instructions Manual page 249

Setting the extended ramp-function generator
Procedure
Proceed as follows to set the extended ramp-function generator:
1. Enter the highest possible speed setpoint.
2. Switch on the motor.
3. Evaluate your drive response.
4. Switch off the motor.
5. Evaluate your drive response.
6. Repeat steps 1 ... 5, until you are satisfied with your drive response.
You have set the extended ramp-function generator.
Inverter with CU230P-2 Control Units
Operating Instructions, 11/2013, FW V4.6.6, A5E02430659B AG
– If the motor accelerates too slowly, then reduce the ramp-up time.
An excessively short ramp-up time means that the motor will reach its current limiting
when accelerating, and will temporarily not be able to follow the speed setpoint. In this
case, the drive exceeds the set time.
– If the motor accelerates too fast, then extend the ramp-up time.
– Increase the initial rounding if the acceleration is jerky.
– We recommend that you set the final rounding to the same value as the initial
rounding.
– If the motor decelerates too slowly, then reduce the ramp-down time.
The minimum ramp-down time that makes sense depends on your particular
application. Depending on the Power Module used, for an excessively short ramp-
down time, the inverter either reaches the motor current, or the DC link voltage in the
inverter becomes too high. Depending on the inverter setting, the real braking time
exceeds the set ramp-down time, or the inverter goes into a fault condition when
braking.
– Extend the ramp-down time if the motor is braked too quickly or the inverter goes into
a fault condition when braking.
Setting functions
8.4 Setpoint calculation
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