Approach And Retraction Behavior (Norm/Kont/Kontc/Kontt) - Siemens SINUMERIK 840D sl Function Manual

W1: Tool offset
18.5 Tool radius compensation 2D (TRC)
Intermediate blocks
In general, only program blocks with positions on geometry axes in the current plane are
programmed when TRC is active. However, dummy blocks can still also be programmed with
active TRC. Dummy blocks are program blocks, which do not contain any positions on a
geometry axis in the current plane:
● Positions on the infeed axis
● Auxiliary functions,
● etc.
The maximum number of dummy blocks can be defined in the machine data:
MD20250 $MC_CUTCOM_MAXNUM_DUMMY_BLOCKS (Max no. of dummy blocks with no
traversing movements for TRC).
Special points to be noted
● TRC can only be selected in a program block with G0 (rapid traverse) or G1 (linear
interpolation).
● A tool must be loaded (T function) and the tool cutting edge (tool compensation) (D1 to
D9) activated no later than in the program block with the tool radius compensation selection.
● Tool radius compensation is not selected with a tool cutting edge/tool compensation of D0.
● If only one geometry axis is programmed on the plane when tool radius compensation is
selected, the second axis is automatically added on the plane (last programmed position).
● If no geometry axis is programmed for the current plane in the block with the tool radius
compensation selection, no selection takes place.
● If tool radius compensation is deselected (G40) in the block following tool radius
compensation selection, no selection takes place.
● If tool radius compensation is selected, the approach behavior is determined by the NORM/
KONT instructions.
18.5.3

Approach and retraction behavior (NORM/KONT/KONTC/KONTT)

NORM and KONT
The NORM and KONT instructions can be used to control approach behavior (selection of tool
radius compensation with G41/42) and retraction behavior (deselection of tool radius
compensation with G40):
Command
NORM
KONT
KONTC
KONTT
1404
Significance
Normal setting at start point/end point (initial setting)
Follow contour at start point/end point
Approach/retraction with constant curvature
Approach/retraction with constant tangent
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions