HEIDENHAIN TNC 320 User Manual page 84

Please note while programming:
Program a positioning block for the starting point (hole
center) in the working plane with radius compensation R0.
The algebraic sign for the cycle parameter DEPTH
determines the working direction. If you program
DEPTH=0, the cycle will not be executed.
If you have entered the bore hole diameter to be the same
as the tool diameter, the TNC will bore directly to the
entered depth without any helical interpolation.
An active mirror function does not influence the type of
milling defined in the cycle.
Note that if the infeed distance is too large, the tool or the
workpiece may be damaged.
To prevent the infeeds from being too large, enter the
maximum plunge angle of the tool in the ANGLE column of
the tool table. The TNC then automatically calculates the
max. infeed permitted and changes your entered value
accordingly.
Danger of collision!
Use the machine parameter displayDepthErr to define
whether, if a positive depth is entered, the TNC should
output an error message (on) or not (off).
Keep in mind that the TNC reverses the calculation for pre-
positioning when a positive depth is entered. This
means that the tool moves at rapid traverse in the tool axis
to set-up clearance below the workpiece surface!
84 Fixed Cycles: Drilling