Siemens SIMATIC EM 148-FC Manual page 46

Functions and Technical Specifications
Ramp-up time
This parameter controls the acceleration of the motor. The motor accelerates from
the minimum to the maximum parameterized motor frequency in the time specified.
Note
If the ramp-up time set is too short, this can result in the converter switching off
due to excess current.
Example of parameterization via the DDB File:
Desired ramp-up time = 30 s
Time factor = 1 s
Max. possible ramp-up time = 510 s
Max. parameter value = 255
Parameter value = ramp-up time *
Parameter value = 30 s *
This formula only applies when f
Ramp-down time
This parameter controls the deceleration of the motor. The motor brakes from the
maximum to the minimum parameterized motor frequency in the time specified.
Note
If the ramp-down time set is too short, this can result in the converter switching off
due to overvoltage.
4-12
Max. parameter value
Max. ramp-up time * time factor
255
= 15
510 s * 1
= f
max setpoint
EM 148-FC Frequency Converter
A5E00065321-03