Chapter - State Based Design

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Chapter - State Based Design
Systems have modes of operation. The controller
should move sequentially between these states
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State Diagrams
General Rules For Construction 1. Consider the
system, What does the system do normally? Does
the system behavior change? Can something change
how the system behaves? Is there a sequence to
actions? 2. List modes of operation where the
system is doing one identifiable activity that
will start and stop. Keep in mind that some
activities may just be to wait.
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Construct a state diagram for an elevator
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Consider the Intersection below
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Draw a reasonable state diagram
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Convert the state diagram to ladder logic using
block logic methods
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A Priority Problem
Convert the following state diagram to ladder
logic
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Write the Boolean equations for the state diagram
below
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Convert the equations to ladder logic using the
Delayed Update method
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Convert the state diagram to ladder logic using
state transition equations
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Example
Develop a control description for an injection
molding machine with the different methods
described in this chapter. Develop ladder logic
for the one that is best suited.