Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 641)

Skip and Gauge probing Cycles
Chapter 19
19-3
Important: The move that immediately follows a G31 series external skip
block cannot be a circular move.
The coordinates of the axes when the external skip signal is received are
available as the paramacro system parameters #5061-#5066 (work
coordinate system) and #5071-#5076 (machine coordinate system). These
values have been adjusted to compensate for the probe tip radius if a radius
compensation value was entered.
For example, assume you have entered a probe tip radius of .01. It is
triggered as axis 2 approaches in the positive direction at the axis 2
coordinate of 1.1200. The value available for paramacro parameter #5072
would be 1.1300.
Your system installer defines probe tip radius in AMP. You can also
change this value through the paramacro system parameter #5096. See
chapter 20 for details on paramacro parameters.
Skip Function Application Example
A typical application for these G codes would be to mount the probe as if it
were a wheel. When the probe contacts the part and triggers, coordinate
data would be available in the paramacros for use in the remainder of the
part program.
The probe tip radius would be significant for this application.
Wheel gauging functions are similar to external skip functions. The
difference is that the wheel gauging functions use the actual wheel position
(when the external skip signal is received) to enter values in the wheel
offset table for the currently active offset.
Use wheel gauging functions to terminate the execution of motion
commands in a block and modify offset tables when the control receives a
signal through PAL. When the program block is terminated any remaining
axis motion generated by the block that has not been performed remains
unexecuted (other non-motion commands are still performed). The current
tool position is stored, and the control continues program execution at the
beginning of the next block following the skipped block.
The gauging function is controlled by G37, G37.1, G37.2, G37.3, and
G37.4. Your system installer determines what signal (such as a touch
probe, manual switch, etc.) corresponds to each G37 code in PAL. Your
system installer can choose different signals to correspond to G37, G37.1
G37.2, G37.3, and G37.4. G37 and G37.1 are functionally the same,
always using the same external signal and the same AMP defined feedrate.
19.2
Wheel Gauging External
Skip Functions (G37 Codes)