Position-Controlled Spindle Operation (Spcon, Spcof) - Siemens SINUMERIK 840DE Programming Manual

Caution
Internal preprocessor stop
If a command, which implicitly causes a preprocessing stop, is read in a following block, this
block is not executed until all other blocks, which are already preprocessed and stored have
been executed. The preceding block is halted in exact stop (as with G9).
Traveling with POS[...]=
The next block is only executed when all axes programmed under POS have reached their
end positions.
Traveling with POSP[...]=
POSP is deployed especially for programming oscillating motions, see
/PGA/, Programming Guide Advanced chapter "Asynchronous Oscillation".
Wait for end of travel with WAITP(...)
After WAITP, assignment of the axis to the NC program is no longer valid; this applies until
the axis is programmed again. This axis can then be operated as a positioning axis through
the PLC, or as a reciprocating axis from the NC program/PLC or HMI.
Block change in the braking ramp with IPOBRKA and WAITMC(...)
An axis is only decelerated if the marker has not yet been reached or if a different search
criterion prevents the block change. After a WAITMC, the axes start immediately if no other
search criterion prevents block change.
7.3

Position-controlled spindle operation (SPCON, SPCOF)

Function
In some cases it may make sense tooperate spindles via position control. For example, a
higher quality can be achieved for thread cutting operations with G33 and a large pitch.
Note: The command requires up to three interpolation cycles.
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
7.3 Position-controlled spindle operation (SPCON, SPCOF)
Feedrate Control and Spindle Motion
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