2 measuring (cycle 3), Cycle run, Please note while programming – HEIDENHAIN TNC 640 (34059x-01) Cycle programming User Manual
Page 505

HEIDENHAIN TNC 640
505
1
8
.2 MEA
S
URING (Cy
c
le 3)
18.2 MEASURING (Cycle 3)
Cycle run
Touch Probe Cycle 3 measures any position on the workpiece in a 
selectable direction. Unlike other measuring cycles, Cycle 3 enables 
you to enter the measuring range SET UP and feed rate F directly. Also, 
the touch probe retracts by a definable value after determining the 
measured value MB.
1
The touch probe moves from the current position at the entered 
feed rate in the defined probing direction. The probing direction 
must be defined in the cycle as a polar angle.
2
After the TNC has saved the position, the touch probe stops. The 
TNC saves the X, Y, Z coordinates of the probe-tip center in three 
successive Q parameters. The TNC does not conduct any length 
or radius compensations. You define the number of the first result 
parameter in the cycle.
3
Finally, the TNC moves the touch probe back by that value against 
the probing direction that you defined in the parameter MB. 
Please note while programming:
The exact behavior of Touch Probe Cycle 3 is defined by 
your machine tool builder or a software manufacturer who 
uses it within specific touch probe cycles.
The DIST (maximum traverse to touch point) and F (probing 
feed rate) data from the touch-probe table, which are 
effective in other measuring cycles, do not apply in Touch 
Probe Cycle 3.
Remember that the TNC always writes to four successive 
Q parameters. 
If the TNC was not able to determine a valid touch point, 
the program is run without error message. In this case the 
TNC assigns the value –1 to the 4th result parameter so 
that you can deal with the error yourself.
The TNC retracts the touch probe by no more than the 
retraction distance MB and does not pass the starting point 
of the measurement. This rules out any collision during 
retraction.
With function FN17: SYSWRITE ID 990 NR 6 you can set 
whether the cycle runs through the probe input X12 or 
X13.
