HEIDENHAIN TNC 620 Programming Station

Programming contours | Approaching and departing a contour
5
NOTICE
Danger of collision!
The control does not automatically check whether collisions
can occur between the tool and the workpiece. Incorrect pre-
positioning and incorrect auxiliary points P
H
can also lead to
contour damage. There is danger of collision during the approach
movement!
Program a suitable pre-position
Check the auxiliary point P
H
, the sequence and the contour
with the aid of the graphic simulation
With the APPR LT, APPR LN and APPR CT functions, the
control moves the tool to the auxiliary point P
H
at the
last programmed feed rate (which can also be FMAX).
With the APPR LCT function, the control moves to the
auxiliary point P
H
at the feed rate programmed with the
APPR block. If no feed rate is programmed yet before the
approach block, the control generates an error message.
Polar coordinates
You can also program the contour points for the following approach/
departure functions over polar coordinates:
APPR LT becomes APPR PLT
APPR LN becomes APPR PLN
APPR CT becomes APPR PCT
APPR LCT becomes APPR PLCT
DEP LCT becomes DEP PLCT
Select by soft key an approach or departure function, then press the
orange P key.
Radius compensation
The tool radius compensation is programmed together with the first
contour point P
A
in the APPR block. The DEP blocks automatically
discard the tool radius compensation.
If you program APPR LN or APPR CT with R0, the control
stops the machining/simulation with an error message.
This method of function differs from the iTNC 530
control!
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HEIDENHAIN | TNC620 | Klartext Programming User's Manual | 01/2022