Execution Order And Feedback Loops - ABB RELION REX640 Engineering Manual

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5.1.4
REX640
Engineering Manual
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Figure 43: Application Configuration tool: an example of function block
organization parameters
Cycle Time is automatically set and it cannot be modified.
To automatically calculate the execution order, click Calculate
Execution Order on the tool bar.

Execution order and feedback loops

It is possible to draw a multi-layer configuration logic that contains feedback loops
with the Application Configuration tool. The execution order of logic functions is
calculated automatically in the Application Configuration tool, but it can also be set
manually. If the automatically calculated value causes the function to be executed one
task cycle time after the other logic functions in the same loop, the execution order
number can be set manually to prevent delays, for example, in output activation.
To perceive accurate time stamps from binary input signals to
function blocks, direct logic connection should be used in the
Application Configuration tool. Due to the internal execution order,
time stamps may not be accurate if an additional logic is used to
connect priority signals to function blocks.
Protection and control engineering
Section 5
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