Rockwell Automation SA500 Drive Configuration and Programming - Manual (Page 87)

Application Programming for DPS Drive Control 4-1
C
HAPTER
4
Application Programming
for DPS Drive Control
Distributed Power System drive products are sold only as part of engineered systems.
The application programming required for each engineered system is developed in
response to each customer’s specifications. Information in this chapter is general
enough to apply to most engineered systems; however, implementation details may
vary. Always refer to your wiring diagrams for specific information about your
engineered system.
4.1 AutoMax Tasks
AutoMax tasks are used to implement safety interlocks, coordinate multiple UDCs,
and collect data from UDC modules in the rack. They can access all common memory
and I/O in the AutoMax rack, including the dual port memory in the UDC module.
AutoMax drive control tasks are generally written in PC/Ladder Logic language.
Typically these tasks control the Drive Control register (100/1100) and the I/O Control
register (101/1101). AutoMax tasks can access registers in the UDC’s dual port
memory in the same way as tasks on the UDC module itself, i.e., by declaring them
COMMON.
4.2 UDC Tasks
UDC tasks operate on registers in the UDC dual port memory described in chapter 3,
as well as on local task-specific variables in order to control some application variable
(e.g., speed) and to calculate the required reference values for the selected control
algorithm. The UDC task is sometimes referred to as an “outer” or “major” control loop.
Note, however, that there may be more than one outer loop per task. In this case the
control loops are nested, or “cascaded,” within the UDC task.
UDC tasks must be written in the Control Block language, a language designed
specifically for drive control. To differentiate them from Control Block tasks written for
AutoMax Processors, they must be specified as UDC tasks in the Programming
!
ATTENTION: Only qualified electrical personnel familiar with the
construction and operation of this equipment and the hazards involved
should install, adjust, operate, or service this equipment. Read and
understand this manual and other applicable manuals in their entirety
before proceeding. Failure to observe this precaution could result in
severe bodily injury or loss of life.
ATTENTION: Only qualified Rockwell personnel or other trained
personnel who understand the potential hazards involved may make
modifications to the application tasks. Any modifications may result in
uncontrolled machine operation. Failure to observe this precaution could
result in damage to equipment and bodily injury.