Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018 193
The Ramp Velocity - Negative attribute is a negative value that defines the
maximum negative velocity command output of the Ramp Generator.
Ramp Acceleration
Usage Access Data
Type
Default Min Max Semantics of Values
Optional - FV
Derived from Max
Accel
Get/SSV REAL 0 0
Accel Units
The Ramp Acceleration attribute is a positive value that defines the maximum
acceleration (increasing speed) of the velocity command output by the Ramp
Generator.
Ramp Deceleration
Usage Access Data
Type
Default Min Max Semantics of Values
Optional - FV
Derived from Max
Decel
Get/SSV REAL 0 0
Accel Units
The Ramp Deceleration attribute is a positive value that defines the maximum
deceleration (decreasing speed) of the velocity command output by the Ramp
Generator.
Ramp Jerk Control
Usage Access Data
Type
Default Min Max Semantics of Values
Optional - FV Get/SSV REAL 0 0 100 %
The Ramp Jerk Control attribute sets the percentage of accel or decel time that is
applied to the speed ramp as jerk limited S Curve based on a step change in
velocity. The S Curve time is added ½ at the beginning and ½ at the end of the
ramp. A value of 0 results in no S-Curve, for example, a linear acceleration or
deceleration ramp.
A value of 100% results in a triangular acceleration profile with the peak being the
configured ramp acceleration or deceleration.
As the Jerk Control value increases the derived accelerating jerk value decreases
based on:
0.5 * 0.01 * Jerk Control * Ramp Vel Positive / Ramp Accel
and the decelerating Jerk limit value also decreases according to: