Siemens SINUMERIK 840D sl Function Manual page 83

Automatic stopping for setting of the clamp
If an axis is to be clamped in continuous-path mode, the NC stops the path motion before the
next "Non-rapid traverse block" if the axis has not been clamped by then, i.e., the PLC has
set the feedrate override value to zero.
Parameterization:
MD36052 $MA_STOP_ON_CLAMPING = 'H04' (Special function for clamped axis)
Prerequisites for the PLC user program
• The axis is always clamped when no travel command is pending.
• The axis does not have to be clamped during positioning of the other axes.
• The axis is clamped if the feed rate override of a machining block is not equal to 0.
The following image shows an example of the interface signals and states upon setting of
the axis clamp. The part program blocks N410, N510, N520 and N610 refer to the schematic
example under certain boundary conditions.
Basic logic functions: Axis monitoring, protection zones (A3)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
It can be seen whether the axes are being positioned depending on whether rapid
traverse (G0) is programmed.
The stop command is therefore not set immediately at the beginning of the block
containing the axis, but at the beginning of the next machining block (traversing block,
that is not traversed with rapid traverse).
If the axis is clamped before the next machining block, i.e., the feedrate override is other
than 0 again, no stop is generated.
Detailed description
2.1 Axis monitoring
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