Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set User Manual
Page 246

Servo Parameters
Chapter 7
7-100
Function
The parameters in this section appear only if you have configured the servo
as a spindle. A 9/260 system or a 9/440 system can have up to two
spindles, and a 9/290 system can have up to three spindles. Refer to
chapter 3 for information on the parameter Specifying Axis Types.
Using a 1326 Motor/1394 Drive Combination as a Spindle
Important: This feature is only compatible with 9/440 CNC or 9/260 and
9/290 CNC platforms using the 8520--SM4 servo module connected to a
1394 digital servo drive.
You can configure a 9/Series to use the 1394 drive as a spindle drive.
Since the 1326 is a brushless servo motor, motor commutation and the
velocity loop must be closed by the 9/Series. The hardware limitation
defining the number of spindles supported on your platform still applies
even if using this type of spindle configuration (i.e,. max 2 spindles on
9/440 systems, max 2 spindles on 9/260 systems -- one per servo card, max
3 spindles on 9/290 systems -- one per servo card).
There are two feedback configuration options for 1394 spindles.
Single--device feedback -- This configuration uses the 1326
motor--mounted feedback for motor commutation, and velocity loop
closure. Since the 1326 resolver--based motors have multiple poles per
revolution, it is not possible for the CNC to identify any given point as a
zero for rotational positioning. Because of this limitation, this
configuration can not be used for accurate spindle positioning -- i.e.,
closed--loop spindle operations including solid--tapping, spindle
synchronization, virtual C, are not permitted. Spindle orient and threading
modes are permitted but operate in the same fashion as an analog spindle
with no feedback (simulated feedback is used for threading and “shot--pin”
type open--loop orients must be used). The 1326 high--resolution motor is
operational with a single feedback device, since there is a 1:1 poles per
revolution ratio. This configuration only applies to a 1:1 spindle--to--motor
gear ratio.
Two--device feedback -- This configuration uses the 1326 motor--mounted
feedback for motor commutation and velocity loop closure. A second
feedback device (single marker encoder) must be installed on the spindle
shaft (one to one ratio with the spindle, see the parameter “No of Teeth on
Spindle Shaft”) for position loop closure. This configuration allows
closed--loop spindle operations for a 1326 motor with resolver velocity
feedback.
7.5
Spindle Parameters