Siemens SINAMICS G120C User Manual

8.18.6 Ramp-function generator
The ramp-function generator in the setpoint channel limits the rate change of the speed setpoint
(acceleration). A reduced acceleration reduces the accelerating torque of the motor. As a
consequence, the motor reduces the stress on the mechanical system of the driven machine.
The extended ramp-function generator not only limits the acceleration, but by rounding the
setpoint, also acceleration changes (jerk). This means that the motor does not suddenly
generate a torque.
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 optimal times depend on the application, and can lie in the
range from a few 100ms to several minutes.
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Initial and 󹪝nal rounding permit smooth, jerk-free acceleration and braking.
The ramp-up and ramp-down times of the motor are increased by the rounding times:
• E󹪜ective ramp-up time = p1120 + 0.5 × (p1130 + p1131).
• E󹪜ective ramp-down time = p1121 + 0.5 × (p1130 + p1131).
Table 8-53 Additional parameters to set the extended ramp-function generator
Parameter Description
p1120 Ramp-function generator, ramp-up time (factory setting: 10s)
Accelerating time in seconds from zero speed up to the maximum speed p1082
p1121 Ramp-function generator, ramp-down time (factory setting: 10s)
Braking time in seconds from the maximum speed down to standstill
Advanced commissioning
8.18Setpoint processing
SINAMICS G120C Converters
286 Operating Instructions, 02/2023, FW V4.7 SP14, A5E34263257B AK

Siemens SINAMICS G120C Specifications

General

Brand	Siemens
Model	SINAMICS G120C
Category	Inverter
Language	English