At a Glance

A DFB instances is a copy of a validated DFB type that can be used for programming.

You can create multiple instances of a same DFB type. In this case the inputs/outputs parameters and the variables (public and private) are duplicated. The DFB type code is not duplicated.

You can use the same instance of the DFB multiple times in your application. This operation is nevertheless strongly discouraged.

The DFB instance name must be different from the name of a Control Expert reserved word, a symbol, or from an elementary function (EF) name, or DFB type name.

How to access to a DFB instance

To access a DFB instance, you must use the program Control Expert.

DFB instances are accessed via the Variables & FB instances directory in the project browser.

Accessing DFB instances via the Derived FB instances directory

To access the DFB instances via the Derived FB instances directory, you must do the following:

Step	Action
1	From the project browser structural view, expand the directoryVariables & FB instances.
2	Double-click on the folder Derived FB instances. Result: The data editor window is opened. It is automatically placed under the Function Blocks register tab. The list of instances already in the system is displayed.