Ramp-Function Generator - Siemens SINAMICS S120 Function Manual

2.9

Ramp-function generator

Description
The ramp-function generator is used to limit acceleration in the event of abrupt setpoint
changes, which helps prevent load surges throughout the drive train. The ramp-up time
p1120[D] and ramp-down time p1121[D] 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[D] is used as a reference value for calculating the ramps from
the ramp-up and ramp-down times. A special adjustable ramp can be set via p1135 for quick
stop (OFF3), e.g. for rapid controlled deceleration when an emergency OFF button is
pressed.
There are two types of ramp-function generator:
● Basic ramp-function generator with
● Extended ramp-function generator also has
Properties of the basic ramp-function generator
Figure 2-9
● RFG ramp-up time Tup p1120[D]
● RFG ramp-down time Tdn p1121[D]
Drive functions
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
– Acceleration and deceleration ramps
– Ramp for quick stop (OFF3)
– Tracking can be selected via a binector input
– Setting values for the ramp-function generator
– Initial and final rounding off
Note
The ramp-function generator cannot be frozen (via p1141) in jog mode (r0046.31 = 1).
Ramp-up and ramp-down with the basic ramp-function generator
Extended setpoint channel
2.9 Ramp-function generator
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