Siemens SINUMERIK 840D sl Function Manual page 191

Scope of the path criterion
● ADIS or ADISPOS must be programmed. If the default is "zero", G641 behaves like G64.
● If only one of the blocks involved is rapid traverse G0, the smaller rounding distance applies.
● If a very small value is used for ADIS, the controller must make sure that every interpolated
block, even an intermediate rounding block, contains at least one interpolation point. The
maximum path velocity is thereby limited to ADIS / interpolator cycle.
● Irrespective of ADIS and ADISPOS, the rounding area is limited by the block length.
In blocks with short distances (distance < 4* ADIS and < 4 * ADISPOS respectively), the
rounding distance is reduced so that a traversable part of the original block is retained. The
remaining length depends on the axis path and is approximately 60% of the distance still
to be traversed in the block. ADIS or ADISPOS is therefore reduced to the remaining 40%
of the distance to be traversed. This algorithm prevents a rounding block being inserted for
a very small change in contour. In this case, switchover to continuous-path mode G64 is
automatic until rounding blocks can be inserted again.
Figure 4-4
Activation/deactivation
Continuous-path mode with rounding based on a path criterion can be activated in any NC
part program block by the modal command G641. Before or on selection, the path criteria
ADIS/ADISPOS must be specified.
Selecting the exact stop which works on a block-by-block basis enables rounding to be
interrupted (G9).
Continuous-path mode with rounding based on a path criterion (G641) can be deactivated by
selecting:
● Modal exact stop (G60)
● Continuous-path mode G64, G642, G643, G644 or G645
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Path with limitation of ADIS
B1: Continuous-path mode, Exact stop, Look Ahead
4.3 Continuous-path mode
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