Adding a Symbol Configuration

Prerequisites

Variables that will be exchanged between the controller and (multiple) HMI devices using the transparent Machine Expert protocol must be published in the controller using the Symbol configuration. They will then be available as EcoStruxure Machine Expert variables in Vijeo-Designer, EcoStruxure Operator Terminal Expert, or OPC server.

Defining a Symbol Configuration

In order to get the symbol configuration functionality available, add the symbol configuration object to the application in the Tools tree as described in the Opening the Symbol Configuration paragraph. This IECVarAccess.library is automatically added to the Library Manager.

You can define the variables to be exported as symbols in the symbol configuration editor or via pragmas (attribute symbol), which are to be added at the declaration of the variables.

NOTE: Variables of a global variable list (GVL) will only be available in the symbol configuration if at least one of them is used in the programming code.

NOTE: Constants are available in the Symbol configuration if the option Replace constants in the Project Settings > Compile options dialog box is deactivated. For particular constants, you can configure the option explicitly by using the attributes {attribute 'const_replaced'} and {attribute 'const_non_replaced'}.

However, in any case the following is true: Constants in a global variable list (GVL) or in another POU are only available in the Symbol configuration, if the GVL or POU is used in the program code, or if the compiler option Link always is activated in the View > Properties > Build dialog box of the GVL or POU.

Another possibility is provided by the SFC editor: You can define the implicitly created element flags in the element properties for export to the symbol configuration.

The name of a symbol created by the symbol configuration is composed according to the following syntax:

Examples:

MyApplication.PLC_PRG.a

MyApplication.GVL.a

For accessing the variable, define the symbol name completely.

Opening the Symbol Configuration

To open the Symbol configuration, proceed as follows:

Step	Action
1	Select the Application node in the Tools tree, click the green plus button, and select the command Add other objects > Symbol configuration.... Result: The Add Symbol configuration dialog box will be displayed.
2	In the Add Symbol configuration dialog box, optionally configure settings like whether to include comments or not. The settings can be modified later in the Symbol configuration editor.
3	Click the Add button. Result: A Symbol configuration node is created under the Application node in the Tools tree. The Symbol configuration is displayed on the right-hand side.

Step

Action

Select the Application node in the Tools tree, click the green plus button, and select the command Add other objects > Symbol configuration....

Result: The Add Symbol configuration dialog box will be displayed.

In the Add Symbol configuration dialog box, optionally configure settings like whether to include comments or not. The settings can be modified later in the Symbol configuration editor.

Click the Add button.

Result: A Symbol configuration node is created under the Application node in the Tools tree. The Symbol configuration is displayed on the right-hand side.

NOTE: Only one symbol configuration node can be created per device.

For details on the variables interchange between the controller and HMI part, refer to the chapter EcoStruxure Machine Expert Controller-HMI Data Exchange.

Creating Symbol Sets Allowing Different Access Rights for Different Control Clients

A symbol set is a defined set of symbols. If supported by the target device, you can combine different symbols of the application to form symbol sets in the symbol configuration editor. The symbol sets information transferred to the controller with the software download. You can grant access to each symbol set for the individual user groups. The access rights are assigned in the Symbol Rights view of the device editor.

Prerequisites for using symbol sets:

A Symbol Configuration is available in the application.
The Enable symbol sets option is enabled in the settings of the symbol configuration.
The controller has a user management enabled.

In the following example, a user group must be available that is granted the rights required for servicing the plant. The user group Service is by default available for this purpose.

To create a symbol set and assign access rights, proceed as follows:

Step	Action	Comment
1	Open the Communication Settings tab of the device editor to configure the connection to the controller.	–
2	Open the Symbol Configuration editor, and click the button from the toolbar for symbol set configuration.	Result: The Add a New Symbol Set dialog box opens.
3	Enter a name for the set: `startup`.	–
4	In the toolbar of the Add a New Symbol Set dialog box, click the button.	Result: The symbols available in the project are displayed.
5	Select the symbols you want to add to this set and save the project.	–
6	Click the Configure Symbol Rights button.	Result: The Symbol Rights view of the device editor opens.
7	Click the Synchronization button.	Result: The display of symbol sets is synchronized with the device. NOTE: If the user management is not yet enabled on the controller, a dialog box will be displayed, prompting you to do so.
8	Click OK to close the Add a New Symbol Set dialog box.	–
9	Select the Users and Groups view of the device editor, click the Synchronization button, and click Yes to enable the user management.	Result: The Device User Login dialog box opens.
10	Log in. If you log in for the first time, execute the steps as described in the Users and Groups chapter.	Result: After successful login, the configuration of the device user management is displayed in the Users and Groups and Access Rights views.
11	Log in to the controller by executing the command Online > Login and click Yes to confirm that the application is downloaded to the controller.	–
12	After successful login, select the Symbol Rights view, and click the Synchronization button.	Results: The Symbol sets section displays the symbol sets that have been downloaded to the controller for the application (`startup` in this example). The Rights table lists the user groups that are created in the user management of the controller (Administrator and Service in this example). When a symbol set is selected on the left-hand side, the access rights of the individual user groups are displayed on the right-hand side: : access is granted : access is not granted The access allowed for each symbol is defined in the Symbol Configuration editor (read, write, execute).
13	On the left-hand side, select the symbol set `startup`, and double-click the minus signs for Administrator and Service.	Results: The icons change into plus signs . The Administrator and Service groups have access to the symbols in the `startup` symbol set.

You can download modifications performed on a symbol set definition to the controller by executing an online change. When the application is deleted on the controller, the symbol sets are also deleted. When building the application, you can create and save a symbol file in XML format for each symbol set.