Rockwell Automation 1771-QA Stepper Positioning Assembly User Manual - Manual (Page 78)

3–56 Programming and Operation
Publication 1771-UM002A–EN–P – May 2000
Minimum Move Time
A minimum “move in progress” time is required by the stepper
controller module to process the next move of a sequence, and to
evaluate and act on incoming commands. Every move sent from the
stepper controller module to a pulse output expander module must
have a duration long enough to allow the stepper controller module
to service the remaining expander modules, process any new
commands and return to the original expander module before the
move has ended. This minimum move duration must be long enough
to allow any programmed combination of events in any mode of
operation. If not, a programming error and system fault will result.
However, if jog or move data, offsets or overrides are not transferred
to the stepper controller while a profile is being executed, then the
shortest executable move time can be used as stated in Table 3.E.
Table 3.E
Minimum Move Time
No. of
Axes
Worst Case Shortest
Executable
1 65ms 40ms
2 110ms 60ms
3 155ms 80ms