Rockwell Automation D64046.5.1 U MNL WIN DDMC - Manual (Page 20)

Chapter 1
Understanding How a DDMC32 System Works
1-8
You can implement DDMC32 instructions at three different operational
levels, depending on the amount of diagnostics and control that you need
for your application. Each level provides incremental increases in terms of
diagnostic coupling with the control. The figure and table below show the
levels of implementation.
Levels of DDMC32 Implementation
Level 1
Level 2
Level 3
•
Ladder Logic for Control
and Diagnostics
•
DFA Instructions for
Messages
•
Ladder Logic for Control
•
SDS Instruction for
Messages and Diagnostics
•
DFA Instruction for Messages
•
SDS Instruction for Control
and Diagnostics
•
DFA Instruction for Messages
Important: A Level 3 Implementation does not limit you to only using the
SDS instruction for control and diagnostics. You may also include Level
1 and Level 2 Implementations for diagnostics outside of the Level 3 SDS
instruction, for example, lube faults or overloads.
The DFA instruction can be used on all levels since it is
used for global type errors. Unlike the SDS instruction, which
is constructed around a given mechanism and its associated
I/O, the DFA instruction is constructed around constantly
monitored conditions that do not fit into a state structure.
Description of DDMC32 Levels
This level Uses this
DDMC32
instruction Control is handled by: Diagnostics are
handled by: Message
Generation is
handled by:
1 DFA ladder logic ladder logic DFA
2 SDS and DFA ladder logic SDS SDS and DFA
3 SDS and DFA SDS and ladder logic SDS SDS and DFA
A typical DDMC32 system applies the following system components:
6400 Series Software
Monitoring software (6404-DDMC)
6200 Series Software
PLC-5 family of programmable controllers
Implementing DDMC32
Instruction in Levels
DDMC32 System Components