Ramp-Function Generator - Siemens SINAMICS G120 Original Instructions Manual

8.4.6

Ramp-function generator

The ramp-function generator in the setpoint channel limits the rate that the speed setpoint
changes. As a consequence the motor accelerates and brakes more softly, reducing the
stress on the mechanical system of the driven machine.
The ramp-function generator is not active if the technology controller in the inverter specifies
the speed setpoint.
Simple ramp-function generator
This inverter always uses the extended ramp-function generator. Consequently, the simple
ramp-function generator is not described in this manual.
Extended ramp-function generator
The ramp-up and ramp-
down times of the extended
ramp-function generator can
be set independently of each
other. The optimum times
that you select depend on
your particular application in
question and can range from
just a few 100 ms (e.g. for
belt conveyor drives) to
several minutes (e.g. for
centrifuges).
Initial and final rounding
permit smooth, jerk-free
acceleration and braking.
The ramp-up and ramp-down times of the motor are increased by the rounding times:
• Effective ramp-up time = p1120 + 0.5 × (p1130 + p1131).
• Effective ramp-down time = p1121 + 0.5 × (p1130 + p1131).
Inverter with CU230P-2 Control Units
Operating Instructions, 11/2013, FW V4.6.6, A5E02430659B AG
Setting functions
8.4 Setpoint calculation
247