Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 310)

Acc/Dec Parameters
Chapter 10
10-14
This is a simplified procedure for determining the Dec Ramp value in
cases where it is critical to axis performance:
Important: The deceleration ramp value may be slightly higher than the
acceleration rate due to friction.
Figure 10.7
Matching S--Curve Dec Ramp to the Natural Response of the Axis
Time (seconds)
Feedrate
Rapid
Natural response
curve of axis
S--Curve Dec Ramp
(slope of this line)
Function
This parameter determines the acceleration or deceleration time for all
manual moves.
“Manual” moves refers to manual jog, incremental jog and handwheel jog
moves. These moves always use exponential Acc/Dec.
The value entered here indicates the number of “coarse iterations” that
make up an Acc/Dec time constant. A coarse iteration is one of the
control’s software timing cycles and is equal to one system scan time. The
Acc/Dec time constant represents the amount of time required to accelerate
or decelerate 63% of the way to the commanded speed (refer to
Figure 10.1).
10.8
Manual Delay Constant