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Chapter 2
Module Overview and Features
Introduction to Scheduled
Output Module
16
High Speed Applications
Packaging machines or sorters that have fast part cycles are often bottlenecked
by controller scan times. By switching to a time-based solution, you can
remove many scan time critical components of the system. This programming
technique allows you to do predictive events and schedule outputs to run
things like diverters without having a scan time to match the part cycle time.
Motion Control
CIP Sync also provides a common time reference for distributed VFD drives,
servos, and controllers throughout the system. This allows controllers to
request axes, reach a predefined position at a known time reference, or run at
a set speed using the same reference. Since all drives and controllers in the
system have the same reference to time, the controller can issue simple
requests for axes to reach target positions in a synchronized fashion.
Global Position Registration
Registration refers to a function usually performed by the drive where a
physical input is triggered causing the drive to precisely capture the actual axis
position when the input event occurred. Rather than wiring inputs to the
registration input on all of the drives, this time-based system lets you wire an
input to only one time based SOE input module. The timestamp returned for
that input, can be used by the motion planner to calculate the actual axis
position at the time the input triggered. This simplifies system installation,
reduces wiring costs, and provides a global machine registration for all the
axes in the system through one SOE input.
The 1732E-OB8M8SR Scheduled Output module is designed to work in
conjunction with the MAOC motion instruction to provide position-based
output control (also known as PLS). The MAOC instruction by itself allows
position-based output control using the position of any motion axis in
ControlLogix as the position reference and any output or boolean as the
output. The MAOC updates the outputs based on motion axis position at the
motion group coarse update rate (typically 2...10 ms). While this is adequate for
some applications, it is too slow for many high speed applications typically
found in converting and packaging segments. The 1732E-OB8M8SR module
improves performance by supporting the ability to schedule the output turn-
on/turn-off time of its 8 outputs (outputs 0...7) in 1 μs increments. Outputs are
scheduled by entering data into one or more of the 16 schedules provided by
the output connection data store.
IMPORTANT When using the 1732E-OB8M8SR module with the MAOC instruction, make
sure that you are using Studio 5000 Logix Designer, version 21 or later. You
must also select Yes for MAOC support and Per Point under Time Stamping.
Operation
This scheduled output implementation schedules outputs on a per point basis
and each individual output point is controlled by its own timestamp.
Individual schedules are created in the controller, stored in the output image
table for the module, and sent over the backplane to the Scheduled Output
module. The schedule specifies a sequence count, the output point to be
associated with the schedule, the time at which an output value should be
applied to the physical output point, and the value to be applied at the
Rockwell Automation Publication 1732E-UM003D-EN-E - November 2021
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