Rockwell Automation 1771-QA Stepper Positioning Assembly User Manual - Manual (Page 69)

3–47 Programming and Operation
Publication 1771-UM002A–EN–P – May 2000
RT = 3 seconds
FR = 10k pulses per second
IR = 2k pulses per second (final rate of previous move)
DT = 0 (decel time is zero in all moves except the last in the
continuous mode, by definition)
Find DELPOS, then add this figure to the final position of the
previous move (100K) to determine the minimum final position that
can be programmed for the move.
3(10k + 2k)
+ 10k + 0.02 < 26k
2 2
0
18k + 0.2K <DELPOS
18.2k <DELPOS
The move final position value must be at least 18.2k pulses beyond
the previous move in order to ensure that the final rate will be
maintained for 20ms. Therefore the minimum allowable
programmed final position for the move is 118,200 pulses, obtained
from adding the calculated value (18.2k) to the final position of the
previous move (100k).
Example Problem 3: Last Move in a Continuous Mode
The last move of a continuous profile must stop at a final position of
742k pulses. Determine if a selected decel time of 2 seconds is
acceptable if the final rate and final position of the previous move
were 12k pulses per second and 680k pulses, respectively, and the
ramp time and final rate (before decel) of the current move are RT =
6 seconds and FR = 6k pulses per second, respectively.