Examples of attribute references to different elements

Note: Attribute references to the same element only work for attributes that have PI point data references configured. See PI point data references.

You can reference attributes that belong to different elements in the following ways:

• Directly from the top of the element hierarchy in the database.

• Specify the parent element of the target attribute using a relative path.

Attributes relative to database

To reference an attribute based on a path relative to the root of the PI AF database, specify the entire element and attributes path from the database. Start the path with a backslash (\), and use the backslash to separate element levels. Precede the attribute with the pipe symbol (|). For example:

\Reactors\React1|pressure

This example assumes that the Reactors element is at the top level of the element hierarchy. You can always use this notation to reference an attribute relative to the top level of elements in the database.

For example, suppose you have the element hierarchy shown in the following illustration:

Assume you want to reference an attribute called pressure, belonging to the NewTank element. You can type:

\Tanks\Tank1\NewTank|pressure

If you want to represent a child attribute of pressure called temp, the reference is:

\Tanks\Tank1\NewTank|pressure|temp

Attributes relative to containing element

You can reference attributes relative to the containing element of the attribute that you are configuring. Use backslashes (\) to move down the element hierarchy and .. to move up the element hierarchy.

In the above illustration, each element (Tank1, Tank2, Tank3, and NewTank) has a pressure attribute:

These examples demonstrate the syntax to:

• Reference a sibling element:

  To refer to the Tank2 attribute pressure from Tank1, type:

  ..\Tank2|pressure

• Reference a parent element:

  To refer to the Tank1 attribute pressure from NewTank, type:

  ..\|pressure

• Reference a child element:

  To refer to the NewTank attribute pressure from Tank1, type:

  .\NewTank|pressure