Siemens Sinumerik 840D sl Programming Manual page 113

Further information
Positioning with SPOSA
The block step enable or program execution is not affected by SPOSA. The spindle positioning
can be performed during execution of subsequent NC blocks. The program moves onto the
next block if all the functions (except for spindle) programmed in the current block have reached
their block end criterion. The spindle positioning operation may be programmed over several
blocks (see WAITS).
Note
If a command, which implicitly causes a preprocessing stop, is read in a following block,
execution of this block is delayed until all positioning spindles are stationary.
Positioning with SPOS/M19
The block step enabling condition is met when all functions programmed in the block reach
their end-of-block criterion (e.g. all auxiliary functions acknowledged by the PLC, all axes at
their end point) and the spindle reaches the programmed position.
Velocity of the movements:
The velocity and the delay response for positioning are stored in the machine data. The
configured values can be modified by programming or by synchronized actions, see:
● Feedrate for positioning axes / spindles (FA, FPR, FPRAON, FPRAOF) (Page 114)
● Programmable acceleration override (ACC) (option) (Page 118)
Specification of spindle positions:
As the G90/G91 commands are not effective here, the corresponding dimensions apply
explicitly, e.g. AC, IC, DC, ACN, ACP. If no specifications are made, traversing automatically
takes place as for DC.
Synchronize spindle movements with WAITS
WAITS can be used to identify a point at which the NC program waits until one or more spindles
programmed with SPOSA in a previous NC block reach their positions.
Example:
Program code
N10 SPOSA[2]=180 SPOSA[3]=0
...
N40 WAITS(2,3)
Fundamentals
Programming Manual, 01/2015, 6FC5398-1BP40-5BA2
8.4 Positioning spindles (SPOS, SPOSA, M19, M70, WAITS)
Comment
; The block waits until spindles 2 and 3 have
reached the positions specified in block N10.
Feed control
113