Optimizing The Motor Startup For Application Class Standard Drive Control - Siemens SINAMICS G120 Operating Instructions Manual

Advanced commissioning
6.24 Motor control
6.24.2.3

Optimizing the motor startup for application class Standard Drive Control

After selecting application class Standard Drive Control, in most applications no additional
settings need to be made.
At standstill, the inverter ensures that at least the rated motor magnetizing current flows.
Magnetizing current p0320 approximately corresponds to the no-load current at 50% ... 80%
of the rated motor speed.
In the following circumstances, the motor cannot accelerate to its speed setpoint after it has
been switched on:
● Load moment of inertia too high
● Load torque too large
● Ramp-up time p1120 too short
The current can be increased at low speeds to improve the starting behavior of the motor.
Starting current (boost) after selecting the application class Standard Drive Control
Requirements
● Set the ramp-up time of the ramp-function generator to a value 1 s (< 1 kW) ... 10 s
(> 10 kW), depending on the power rating of the motor.
● Increase the starting current in steps of ≤ 5%. Excessively high values in p1310 ... p1312
can cause the motor to overheat and switch off (trip) the inverter due to overcurrent.
If message A07409 appears, it is not permissible that you further increase the value of any
of the parameters.
Procedure
Proceed as follows to set the voltage boost:
1. Switch on the motor with a setpoint of a few revolutions per minute.
2. Check whether the motor rotates smoothly.
3. If the motor does not rotate smoothly, or even remains stationary, increase the voltage
boost p1310 until the motor runs smoothly.
4. Accelerate the motor to the maximum speed with maximum load.
5. Check that the motor follows the setpoint.
6. If necessary, increase the voltage boost p1311 until the motor accelerates without problem.
In applications with a high break loose torque, you must also increase parameter p1312 in
order to achieve a satisfactory motor response.
You have set the voltage boost.
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Converter with the CU230P-2 Control Units
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34257946B AE