Specification sets

About specification sets

Specification sets provide information about how a simulation was designed by grouping variables for which you have changed the default specification status. AVEVA Process Simulation automatically creates specification sets as you change the specification status for variables. When you change a simulation so that the simulation is no longer properly specified, the software creates and opens a specification set. The specification set includes any variables for which you change the default specification status until the simulation is once again properly specified. When the simulation is again properly specified, the software closes the specification set.

While adding flowsheet equations affects whether the simulation is properly specified, specification sets do not account for the impact of flowsheet equations. Therefore, a specification set can include an odd number of variables.

If a Scenario changes the specification status of any variables, the specification sets change as the Scenario runs.

Specification sets typically contain only two variables, since the simulation switches between improperly and properly specified as you swap the specification status for two variables. However, when the Auto Solve feature and the specifications analysis are turned off, the specification sets can contain any number of variables, since the simulation does not return to a properly specified state until you solve the simulation. See Turn off the specifications analysis while manually solving your simulation for more information.

AVEVA Process Simulation automatically merges specification sets when you remove variables from the list of changed specifications. You remove variables from the list by doing one of the following:

• Change the variable back to its default specification status.

• Change the configuration parameters for a model instance so that the model instance no longer includes the variable.

• Delete the variable from the Model Type by using the Model Editor.

If the removed variable was part of a closed specification set and there are no other open specification sets, the software keeps the modified specification set open until the simulation is once again properly specified.

If the removed variable was part of a closed specification set and there is an existing open specification set, the software merges the two specifications sets into a single specification set.

If the removed variable was part of an open specification set, the software simply removes the variable and deletes the specification set if it doesn't include any other variables.

Concepts

• A specification set can include multiple variables

• When specifications analysis is turned on, specification sets typically include only two variables

• AVEVA Process Simulation automatically creates and opens a specification set when you change a simulation so that the simulation is no longer properly specified

• AVEVA Process Simulation closes a specification set when the simulation is once again properly specified

• AVEVA Process Simulation automatically merges or deletes specification sets when you remove variables from the list of changed specifications

• You currently cannot rename specification sets or move variables between specification sets

Actions

• Create specification sets by changing the specification status of variables

• Sort and filter variables in the Changed Specifications window or Properties Inspector by specification set (that is, the values in the Set column)