Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 747)

Section 15A
Troubleshooting the Control
15A-37
When the probe is not fired, the following error magnitude equals the
probe deflection from the probes zero point. Once the probe is fired, the
following error shows:
- the actual following error for the adaptive depth probe axis if the
probe is AMPed to close the position loop for another axis.
- the probe deflection relative to the probes zero point if the probe is
not AMPed to close the position loop for another axis.
Important: The following error display is invalid for the block that
initially fires the adaptive depth probe, and the block that pulls out of the
hole releasing the adaptive depth probe.
The distance to marker value for the spindle is updated in both open- and
closed-loop spindle operation. The following error is updated only during
closed-loop spindle operation. Information for spindle servos following
error is valid only when the spindle is in one of these closed-loop modes:
orient
solid tapping
virtual C
The control does not cancel following error when a spindle transitions
from closed-loop mode to open-loop mode.
The axis units of INCH, MM or DEG are displayed after the axis name.