Ramp-Function Generator - Siemens SINAMICS S120 Function Manual

Extended setpoint channel

3.6 Ramp-function generator

3.6 Ramp-function generator
Function of the ramp-function generator
The ramp-function generator is used to limit the acceleration in the event of abrupt setpoint
changes and so helps to prevent load surges throughout the complete drive train. The ramp-
up time p1120[0...n] and ramp-down time p1121[0...n] can be used to set mutually
independent acceleration and deceleration ramps. This allows a controlled transition to be
made in the event of setpoint changes.
The maximum speed p1082[0...n] is used as a reference value for calculating the ramps
from the ramp-up and ramp-down time. For a quick stop (OFF3), a special adjustable ramp
is available via the ramp-down time p1135[0...n] (e.g. for quick, controlled stopping after an
EMERGENCY OFF button has been pressed).
There are two types of ramp-function generator:
● Basic ramp-function generator with
– Ramp up and ramp down
– Ramp down for quick stop (OFF3)
– Tracking configurable via parameter p1145
– Setting values for the ramp-function generator
● The extended ramp-function generator also has
– Initial and final rounding
Note
The ramp-function generator cannot be frozen (via p1141) in jog mode (r0046.31 = 1).
Properties of the basic ramp-function generator
Figure 3-8
● Ramp-up time T
● Ramp-down time T
76
Ramp-up and ramp-down with the basic ramp-function generator
p1120[0...n]
up
p1121[0...n]
dn
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
Drive functions