Siemens Sinumerik 840D sl Programming Manual page 231

General conditions
During definition of the protection zones:
• no cutter or tool nose radius compensation must be active.
• no transformation must be active.
• no frame must be active.
Neither must reference point approach (G74), fixed point approach (G75), block
preprocessing stop nor program end be programmed.
Further information
Definition of protection zones
Definition of the protection zones includes the following:
• CPROTDEF for channel-specific protection zones
• NPROTDEF for machine-specific protection zones
• Contour description for protection zone
• Termination of the definition with EXECUTE
You can specify a relative offset for the reference point of the protection zone when the
protection zone is activated in the NC part program.
Reference point for contour description
The workpiece-oriented protection zones are defined in the basic coordinate system.
The tool-oriented protection zones are defined with reference to the tool carrier reference
point F.
Permissible contour elements
The following are permissible to define the contour of the protection zone:
• G0, G1 for straight contour elements
• G2 for clockwise circle segments (only for workpiece-oriented protection zones)
• G3 for circular segments in the counter­clockwise direction
Note
If a full circle describes the protection zone, it must be divided into two half circles. The
sequence G2, G3 or G3, G2 is not permitted. A short G1 block must be inserted, if
necessary.
The last point in the contour description must coincide with the first.
Job planning
Programming Manual, 02/2011, 6FC5398-2BP40-1BA0
3.1 Definition of the protection zones (CPROTDEF, NPROTDEF)
Protection zones
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