Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 117)

Section 3A
Primary 9/230 Components
3A-34
The touch probe circuitry resident on the processor module only responds
to the trigger probe edge changes. Polarity transition (high to low or low
to high) is selectable through the AMP parameter Probe Transition.
Specify the probe transition in AMP as rising edge or falling edge. Once
the active edge occurs, position data is captured , and additional
occurrences of the trigger signal have no effect until the probe is reenabled
under program control.
Refer to the 9/Series CNC 9/230, 9/260, and 9/290 AMP Reference
Manual, publication 8520-6.4, for more information.
ATTENTION: It is preferred, from a safety standpoint, that the
touch probe relay be closed at rest and open when the touch
probe stylus deflects. Then, if a wire breaks or shorts to ground,
it will appear to the system as a probe fired and the probing
cycle in process will stop commanding motion towards the part.
The user should make every effort towards the fail-safe
operation of the touch probe. Not all vendor’s touch probe
control units conform to this safety consideration.
Figure 3A.24 shows the internal processor module circuitry that interfaces
to the touch probe connector. It is shown here to assist you in determining
whether your touch probe hardware is compatible.