Siemens SIMATIC S5 Manual page 114

Note
I
Closed loops without traversing jobs and without dwell times are illegal.
The following pulse diagrams represent traversing movements as speed overtime, The distance
eration and deceleration phases are assumed to be linear.
Interruption during a dwell time
If a machining program is interrupted during a dwell time, the system assumes that the dwell
time has elapsed. The dwell time is aborted, i.e. after the enter command to continue the machin-
ing program, the next traversing job or the next dwell time is processed.
When a dwell time is interrupted, all offsets (e.g. G57 or G43) and switchovers (e.g. G91 ) pro-
grammed before the next dwell time or next traversing job are executed. After this:
the error message "machining program waiting to continue" is set
"position reached" is signalled
the axis status changes to "finished".
When a machining program is interrupted during a dwell time, the break point is therefore always
directly before the next dwell time or before the next traversing job.
N20 G56 ! X200 F500 M20 (! = break point in the program)
a
Interruption during
A machining program can be interrupted at any phase of a single traversing movement. If the
program is interrupted by a stop command or by an operator error, the axis is braked.
A traversing movement can be interrupted as follows:
1, while the axis is accelerating or traveling at a constant speed or
2. in the deceleration phase of the traversing movement.
single traversing movement
Executing Machining Programs
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