Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 581)

Probing Parameters
Chapter 31
31-3
Function
This parameter is used to determine when the control recognizes a signal
from a probe to execute one of the skip or probing functions. The control
recognizes a probe trigger when the probe signal is turned on or off.
Low to High -- When this parameter is set at “Low to High,” the control
recognizes a probe signal when the probe turns on (rising edge of
the signal).
Figure 31.1
Low to High Probe Transition
+5 Vdc
0 Vdc
Position data captured
at first rising edge
of the probe signal
Subsequent rising edges
(due to noise or switch
bounce) have no effect
High to Low -- When this parameter is set at “High to Low,” the control
recognizes a probe signal when the probe turns off (falling edge of
the signal).
Figure 31.2
High to Low Probe Transition
Position data captured
at first falling edge
of the probe signal
Subsequent falling edges
(due to noise or switch
bounce) have no effect
+5 Vdc
0 Vdc
Axis Parameter
Number
All [602]
Range
Selection Result
(a) Low to High
(b) High to Low
31.3
Probe Transition