Rockwell Automation Arena Packaging Users Guide - Manual (Page 73)

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Variables
Overview
Variables are quantities that describe the state of a system. Modeling with the Arena
Packaging template often requires the referencing of variables to make control decisions,
animate the system state, or write statistics.
The Arena Packaging template provides a set of variables for several of the Packaging
modules. These special-purpose variables are automatically defined and assigned values
over the course of a simulation by the Arena Packaging engine. They reference both
dynamic and static information of a modeled system (e.g., equipment run speeds, input
and output rates, conveyor accumulation levels, throughput quantities, storage and tank
levels, etc.).
During a simulation, you can assign, update, or reference Arena Packaging template
variables for logic or presentation purposes.
This chapter contains a description of each of the Arena Packaging template variables.
Special-purpose variables that refer to the standard Arena and SIMAN template constructs
can be found in the Arena Variables Guide and in Arena’s online help.
Organization
Assigning and referencing Arena Packaging template
variables
This section discusses the assignment and referencing of Arena Packaging variables. In
general, Arena Packaging template variables are not user-assignable. However, they can
be referenced for animation or control logic purposes.
Updating Arena Packaging template variables
During a model run, Arena Packaging template variables are not updated continuously. By
default, they are updated only when current values are required by the Arena Packaging
engine. This default updating is sometimes insufficient for use in animation or discrete
logic. This section discusses how to update the variables frequently for smoother anima-
tion and how to update the variables at discrete times using the Actions module.
Variables
This section contains descriptions of all of the Arena Packaging template variables. The
variables are grouped into categories by module (e.g., Machine, Conveyor, etc.).