Siemens sinumerik 840D sl Function Manual page 556

Computing time requirements
The additional computing time required for the "clearance control" technological function
must be taken into account on control systems in which the cycle times set for the
interpolator and position controller cycle have been substantially optimized in comparison
with the default setting:
The additional computing time required comes into effect when clearance control is activated
in the part program (CLC(x)). If the interpolation or position controller cycle is exceeded, the
following alarm appears:
• Interrupt: "4240 Computing time overflow at IPO or position controller level, IP
Execution of the part program is aborted.
Special functions: Clearance Control (TE1)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
part program
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Boundary conditions
3.2 Function-specific boundary conditions
point in
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