Rockwell Automation 8520-GUM 9/Series CNC Grinder Operation and Programming Manual Documentation Set - Manual (Page 352)

Coordinate Control
Chapter 11
11-36
When the grinding machine is set up, your system installer should have
installed a set of two mechanical limit switches on each axis. These limit
switches are installed in a position such that when the machine attempts to
move beyond a range determined by your system installer, the limit switch
trips. When the limit switch trips, axis motion stops. The area defined by
these limit switches is referred to as the hardware overtravel.
ATTENTION: The area defined by a hardware overtravel does
not take into account any wheel offsets. This may allow the
grinding wheel to enter a restricted area without the axes
entering it.
Install these switches to prevent the machine from motion that exceeds a
range that might cause damage to the machine. Frequently your system
installer wires the hardware overtravel directly into the E-STOP string.
This stops all motion and disable the axis drives. See the literature
provided by your system installer for instructions on moving axes out of
hardware overtravel.
The coordinate values of the points defining the software overtravels are
set in AMP by your system installer. This overtravel can be disabled only
by your system installer in AMP. If your system installer has enabled the
software overtravels, the control does not allow the axes to enter the area
defined by the software overtravels.
Figure 11.20
Software Overtravels Established in AMP
Hardware
overtravel
This point (wheel gauge point)
is prohibited from entering
the software overtravel
Software
overtravel
Entry into this
area is prohibited by
the software overtravel
Grinding
wheel
12022-I
11.8.1
Hardware Overtravels
11.8.2
Software Overtravels