Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 311)

Acc/Dec Parameters
Chapter 10
10-15
For all practical purposes, acceleration or deceleration is completed after
five time constants. Therefore, the total acceleration or deceleration time
can be determined by multiplying the value entered here first by 20
milliseconds, and then by 5.
Axis Parameter
Number
Axis Parameter
Number
(1) [1000] (7) [7000]
(2) [2000] (8) [8000]
(3) [3000] (9) [9000]
(4) [4000] (10) [10000]
(5) [5000] (11) [11000]
(6) [6000] (12) [12000]
Range
1 to 100
Notes
This parameter must be set independently for each axis.
This equation can be used to approximate axis speed at any time during
exponential axis acceleration:
Speed = (S
in
) + (S
com
- S
in
)(1 - e -x )
where :
S
in
= Initial axis speed
S
com
= Commanded axis speed
e = the natural antilogarithm
(1000/system scan time)(elapsed time in seconds)
x = -------------------------------------------------
(Manual Delay Constant)
For example, Figure 10.8 shows axis speeds at various times during an
exponential acceleration. This example assumes an initial speed of zero, a
commanded speed of 100 ipm, a system scan time of 20 ms, and a Manual
Delay Constant of 10.
After .2 seconds (one time constant), the axis is moving at a speed of 63
ipm. After .4 seconds, the axis is moving 86 ipm.