Fixed Point Approach; Fixed Point Approach: G75; Reference Point Approach: G74 - Siemens SINUMERIK User Manual

11.6

Fixed point approach

11.6.1

Fixed point approach: G75

Functionality
By using G75, a fixed point on the machine, e.g. tool change point, can be approached. The position is stored permanently
in the machine data for all axes. A maximum of four fixed points can be defined for each axis.
No offset is effective. The velocity of each axis is its rapid traverse.
G75 requires a separate block and acts non-modal. The machine axis identifier must be programmed!
In the part program block after G75, the previous G command of the "Interpolation type" group (G0, G1,G2, ...) is active
again.
Programming
G75 FP=<n> X=0 Z=0
Note
FPn is referencing with axis machine date MD30600 $MA_FIX_POINT_POS[n-1]. If no FP is programmed, then the first
fixed point is selected.
Command
G75
FP=<n>
X=0 Z=0
Programming example
N05 G75 FP=1 X=0
N10 G75 FP=2 Z=0
N30 M30
Note
The programmed position values for X, Z (any value, here = 0) are ignored, but must still be written.
11.6.2

Reference point approach: G74

Functionality
The reference point can be approached in the NC program with G74. The direction and speed information of each axis is
stored in the machine data.
G74 needs a separate block and is active based on the block mode. The machine axis identifier must be programmed!
In the block after G74, the previous G command of the "Interpolation type" group (G0, G1,G2, ...) is active again.
Programming example
N10 G74 X=0 Z=0
Note
The programmed position values for X, Z (here = 0) are ignored, but must still be written.
Programming and Operating Manual (Turning)
01/2017
Significance
Fixed point approach
Fixed point that is to be approached. The fixed point number is specified: <n>
Value range of <n>: 1, 2, 3, 4
MD30610$NUM_FIX_POINT_POS should be set if fixed point number 3 or 4 is to be used.
If no fixed point number is specified, fixed point 1 is approached automatically.
Machine axes to be traversed to the fixed point.
Specify the axes with value "0" with which the fixed point is to be approached simultaneously.
Each axis is traversed with the maximum axial velocity.
; Approach fixed point 1 in X
; Approach fixed point 2 in Z, e.g. for tool
change
; End of program
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