Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 152)

Servo Parameters
Chapter 7
7-6
In general, any servo attached to the CNC counts as a motor (the exception
being a depth probe, which is also configured as an additional motor).
When using the adaptive depth feature, the depth probe is configured as an
axis with no output port but with feedback, and is counted as a motor on
the board. For instance, this parameter would be set to three for a system
that uses two motors and a probe for adaptive depth.
Figure 7.1
Typical Drive and Feedback Connections for a 9/440
Three--axis Machine and Spindle with Feedback and Optional Feedback
Position
feedback as
optional
feedback
Axis 2
9/440 CNC
System Module
Motor 3
Resolver
Touch Probe
Spindle drive
Motor 2
Resolver
Motor 1
Resolver
Axis
Module
Axis
Module
Axis
Module
Encoder
1
Encoder
2
Spindle
motor
Feedback
Devices
Spindle Encoder Position feedback
Velocity feedback
Axis 3
Axis 3
Axis 2
Axis 1
NUMBER OF MOTORS ON 1ST BOARD = Four
NUMBER OF MOTORS ON 2ND BOARD = None
Velocity/Position feedback
with a single feedback device
Velocity
feedback
Position feedback as
optional feedback
Velocity
feedback
Analog
Spindle
drive
J1 J2 J4 J9 J10 J11 J3