Rockwell Automation SD3000 Drive Configuration, Programming - Manual (Page 71)

4.0
APPLICATION PROGRAMMING FOR DPS DRIVE
CONTROL
ONLY QUALIFIED ELECTRICAL PERSONNEL FAMILIAR WITH THE CONSTRUCTION AND
O P E R A T I O N O F T H I S E Q U I P M E N T A N D T H E H A Z A R D S I N V O L V E D S H O U L D I N S T A L L , A D J U S T ,
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.
W A R N I N G
ONLY QUALIFIED RELIANCE 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 THESE PRECAUTIONS COULD RESULT IN DAMAGE TO EQUIPMENT AND BODILY
I N J U R Y
4.1
Distributed Power 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.
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 l/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 (101/1 101). 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 Executive software. Like Control Block tasks on AutoMax
Processors, UDC tasks can include a number of BASIC language statements and functions; however,
those that allow task suspension or delay are not supported.
UDC tasks are created, compiled, loaded, and monitored in the same way as Control Block tasks for
AutoMax Processors. UDC task variables can be monitored, set, tuned, and forced like AutoMax task
variables. Note that the UDC module is accessed for monitoring and loading purposes through the
serial port on the leftmost AutoMax Processor (or over the DCS-NET network), which is used for all
connections to the rack.
4-1