Siemens SIMATIC ET 200pro Series Operating Instructions Manual page 135

3. Evaluate your drive response.
– If the motor accelerates too slowly, then reduce the ramp-up 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
4. Switch off the motor.
5. Evaluate your drive response.
– If the motor decelerates too slowly, then reduce the ramp-down time.
– Extend the ramp-down time if the motor is braked too quickly or the converter goes
6. Repeat steps 1 ... 5 until the drive behavior meets the requirements of the machine or
plant.
You have set the extended ramp-function generator.
Changing the ramp-up and ramp-down times in operation
The ramping up and down time of the ramp-function generator can be changed during
operation. The scaling value can come, e.g. from the fieldbus.
Table 7- 25
Parameter
p1138
p1139
SIMATIC ET 200pro FC-2 converter
Operating Instructions, 09/2017, FW V4.7 SP9, A5E34257324B AE
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.
rounding.
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 converter either reaches the motor current, or the DC link voltage in
the converter becomes too high. Depending on the converter setting, the real braking
time exceeds the set ramp-down time, or the converter goes into a fault condition
when braking.
into a fault condition when braking.
Parameters for setting the scaling
Description
Up ramp scaling (factory setting: 1)
Signal source for scaling the acceleration ramp.
Deceleration ramp scaling (factory setting: 1)
Signal source for scaling the deceleration ramp.
Advanced commissioning
7.9 Setpoint calculation
135