Rockwell Automation Allen-Bradley Micro830

Rockwell Automation Publication 2080-UM002L-EN-E - November 2021 77
Chapter 7
Motion Control
Generally two types of motion control are used in Micro800 controller motion
applications that have Kinetix 3 servo drives.
• Indexed Motion – Micro800 controller issues position
indexes to the
servo drive
using Modbus RTU communications or discrete I/O. Used for
simple positioning. See publication CC-QS025
for building block
example.
• PTO Motion – Micro800 controller uses pu
lse and direction outputs to
the servo drive for precise control of position and v
elocity with Modb
us
RTU
communications or discrete I/O for feedback. Micro800
motion
configuration and instructions make programming easy. See
publication
CC-QS033
for building block example.
PTO Motion Control Certain Micro830, Micro850, and Micro870 controllers, shown in Table 6,
support motion control through high-speed pulse-train outputs (PTO). PTO
functionality refers to the ability of a controller to accurately generate a
specific number of pulses at a specified frequency. These pulses are sent to a
motion device, such as a servo drive, which in turn controls the number of
rotations (position) of a servo motor. Each PTO is exactly mapped to one axis,
to allow for control of simple positioning in stepper motors and servo drives
with pulse/direction input.
As the duty cycle of the PTO can be changed dynamically, the PTO can also be
used as a pulse width modulation (PWM) output.
PTO/PWM and motion axes support on the Micro830, Micro850, and Micro870
controllers are summarized below.
Table 6 - PTO/PWM and Motion Axis Support on Micro830, Micro850, and Micro870
Controller PTO (built-in) Number of Axes Supported
10/16 Points
(1)
2080-LC30-10QVB
2080-LC30-16QVB
(1) For Micro830 catalogs, Pulse Train Output functionality is only supported from firmware revision 2 and later.
11
24 Points
2080-LC30-24QVB
(1)
2080-LC30-24QBB
(1)
2080-LC50-24QVB
2080-LC50-24QBB
2080-LC70-24QBB
2080-LC70-24QBBK
22
48 Points
2080-LC30-48QVB
(1)
2080-LC30-48QBB
(1)
2080-LC50-48QVB
2080-LC50-48QBB
33