Siemens Sinumerik 840D sl Programming Manual page 128

Feed control
8.10 Several feedrate values in one block (F, ST, SR, FMA, STA, SRA)
Note
Delete distance-to-go
If input bit 1 is activated for the dwell time or bit 0 for the return path, the distance to go for the
path axes or the relevant single axes is deleted and the dwell time or return started.
Note
Retraction path
The unit for the retraction path refers to the current valid unit of measurement (mm or inch).
The reverse stroke is always made in the opposite direction to the current motion. SR/SRA
always programs the value for the reverse stroke. No sign is programmed.
Note
POS instead of POSA
If feedrates, dwell time or return path are programmed for an axis on account of an external
input, this axis must not be programmed as POSA axis (positioning axis over multiple blocks)
in this block.
Note
Status query
It is also possible to poll the status of an input for synchronous commands of various axes.
Note
LookAhead
Look Ahead is also active for multiple feedrates in one block. In this way, the current feedrate
can be restricted by the Look Ahead value.
Examples
Example 1: Path motion
Program code
G1 X48 F1000 F7=200 F6=50 F5=25 F4=5 ST=1.5 SR=0.5
128
Comment
; Path feedrate = 1000
; Additional path feedrate values:
; 200 (input bit 7)
; 50 (input bit 6)
; 25 (input bit 5)
; 5 (input bit 4)
; Dwell time 1.5 s
; Retraction 0.5 mm
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
Fundamentals