Superimposing Handwheel Positioning During Program Run: M118 - HEIDENHAIN TNC 426 B User Manual

Input
If you enter M120 in a positioning block, the TNC continues the
dialog for this block by asking you the number of blocks LA that are
to be calculated in advance.
Effect
M120 must be located in an NC block that also contains radius
compensation RL or RR. M120 is then effective from this block until
radius compensation is canceled, or
M120 LA0 is programmed, or
M120 is programmed without LA.
another program is called with PGM CALL
M120 becomes effective at the start of block.
Limitations
After an external or internal stop, you can only re-enter the
contour with the function RESTORE POS. AT N.
If you are using the path functions RND and CHF , the blocks
before and after RND or CHF must contain only coordinates of
the working plane.
If you want to approach the contour on a tangential path, you
must use the function APPR LCT. The block with APPR LCT must
contain only coordinates of the working plane.
If you want to approach the contour on a tangential path, use the
function DEP LCT. The block with DEP LCT must contain only
coordinates of the working plane.
Superimposing handwheel positioning during
program run: M118
Standard behavior
In the program run modes, the TNC moves the tool as defined in
the part program.
Behavior with M118
M118 permits manual corrections by handwheel during program
run. You can use this miscellaneous function by entering axis-
specific values X, Y and Z (in mm) behind M118.
Programming M118
If you enter M118 in a positioning block, the TNC continues the
dialog for this block by asking you the axis-specific values. The
coordinates are entered with the orange axis direction buttons or
the ASCII keyboard.
Effect
Cancel handwheel positioning by programming M118 once again
without X, Y and Z.
M118 becomes effective at the start of block.
HEIDENHAIN TNC 426 B, TNC 430
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Example NC block
You wish to be able to use the handwheel during
program run to move the tool in the working plane
X/Y by ±1 mm of the programmed value:
L X+0 Y+38.5 RL F125 118 X1 Y1
M118 is always effective in the original
coordinate system, even if the working
plane is tilted!
M118 also functions in the Positioning
with MDI mode of operation!
If M118 is active, the MANUAL OPERATI-
ON function is not available after a
program interruption
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