Siemens SINUMERIK 840D sl Programming Manual page 303

No intermediate smoothing blocks
An intermediate smoothing block is not inserted in the following cases:
● The axis stops between the two blocks.
This occurs when:
– The following block contains an auxiliary function output before the motion.
– The following block does not contain a path motion.
– An axis is traversed for the first time as a path axis for the following block when it was
– An axis is traversed for the first time as a positioning axis for the following block when it
– The previous block traverses geometry axes and the following block does not.
– The following block traverses geometry axes and the previous block does not.
– Before tapping, the following block uses G33 as preparatory function and the previous
– A change is made between BRISK and SOFT.
– Axes involved in the transformation are not completely assigned to the path motion (e.g.
● The smoothing block would slow down part program execution.
This occurs:
– Between very short blocks.
– If a block transition G64 (continuous-path mode without smoothing) can be traversed
NC programming
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
previously a positioning axis.
was previously a path axis.
block does not.
for oscillation, positioning axes).
Since each block requires at least one interpolator clock cycle, the added intermediate
block would double the machining time.
without a reduction in velocity.
Smoothing would increase the machining time. This means that the value of the
permitted overload factor (MD32310 $MA_MAX_ACCEL_OVL_FACTOR) affects
whether a block transition is rounded or not. The overload factor is only taken into
account for smoothing with G641 / G642. The overload factor has no effect in the case
of smoothing with G643 (this behavior can also be set for G641 and G642 by setting
MD20490 $MC_IGNORE_OVL_FACTOR_FOR_ADIS to TRUE).
Fundamentals
2.11 Path action
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