8 – 88 HEIDENHAIN Service Manual iTNC 530
Considering the
tool length
If the position display is set to ACTUAL, the operator can see the position of the tool tip. The
tool, however, is not calculated in the log!
The ACTUAL value in the log for the tool axis minus the tool length results in the displayed
ACTUAL value on the monitor of the control.
In this example:
115.5001 - 120.0000 = - 4.4999 (ACTUAL position display of the tool axis Z on the monitor)
Calculating the
REF position
Not the ACTUAL values at the time of the program abortion are interesting for the service
engineer, but the REF values which represent the positions with reference to the machine
datum.
To determine these REF values, the offset values recorded in the log are subtracted (Preset)
from the ACTUAL positions (Actual pos.).
In this example:
Actual pos. Preset REF position
76.6001 - (- 201.7407) = 278.3408 X axis
1.9861 - (- 96.7370) = 98.7231 Y axis
115.5001 - 131.1721 = - 15.6720 Z axis
0.4139 - 332.4911 = - 332.0772 A axis
The REF position of the tool axis Z calculated in the example (- 15.6720), is also displayed
on the control monitor with the position display setting REF.
This display always refers to the datum of the tool holder.
To determine the REF position of the tool tip, the tool length still has to be subtracted
(-15.6720 - 120.0000 = - 135.6720).