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Object: Library Manager

Symbol: _cds_icon_library_manager.png

The Library Manager lists all libraries which have been integrated in the project for creating applications. It provides information about the type of library, its properties, and its contents.

You can expand or collapse the list of integrated libraries, as well as edit library properties for non-dependent libraries.

The Library Manager consists of three views:

  • Upper view: List of the integrated libraries

  • Lower left view: Tree structure with all modules of the library selected in the upper view

  • Lower right view: Documentation for the library POU selected in the tree

For more information, see: Using Libraries and Information for Library Developers

List of integrated libraries

If a library depends on other libraries, then these referenced libraries are automatically integrated.

Displayed in gray fonts

A plug-in was used to automatically add the library to the project.

Displayed in black fonts

The Add Library command was used to automatically add the library to the project.


Display of the integrated library in the following syntax:

<placeholder name> = <library name>, <version> (<company>):

<placeholder name>: When the library is a placeholder library, the placeholder name is before a =.

_cds_icon_unresolved_library.png<placeholder name> = (unresolved): The placeholder library is not resolved.

<library name>: Name of the library that is used for management in the library repository

<version>: Version that was referenced at the first time it was integrated

(<company>): Vendor (optional)


Namespace for unique access to the contents of the library

It is prepended to a module identifier for this purpose:

<namespace>.<library POU identifier>

The namespace usually matches the library name.

Note: If the library has the property LanguageModelAttribute "qualified-access-only", then you have to access the library POU in the application code by means of the namespace. Qualified (unique) access is enforced.

You can modify the standard namespace for local use (within the project) in the Properties dialog.

Effective version

Version of the library after the resolution

This version of the library is used in the application.

Requirement: The Library Manager exists in the Devices view and a placeholder library is selected.



Symbol with tooltip to notify about the current resolution of the selected placeholder library which deviates from the default

Example when the Library Manager is in the Devices view: This placeholder is explicitly redirected to this version (see the Placeholders dialog).

Example when the Library Manager is in the POUs view: In the 'Device_1' device, the placeholder is resolved to 'VisuElemsAlarms, (System)'.


Library which is signed with a trusted certificate (compatible with CODESYS >= V33.5 SP15)


Library which is signed with a trusted certificate, but references at least one unsigned library


Library which is signed with a private key and token (compatible with CODESYS >= V33.5 SP15)


Library which is not signed, or signed with an untrusted or expired certificate

In the case of an untrusted certificate, the Trust Certificate command is provided in the context menu.


Unavailable library or unresolved placeholder library

Hint: Assign an available library to the placeholder. To do this, click the _cds_icon_placeholders.png command icon. There you can edit the placeholder and, for example, assign the newest version or another library.


Library that is defined as optional and not currently available


Library whose status is being determined


Licensed library for which no valid license is currently available


Library symbol for a library that cannot be loaded because its signature (encryption) could not be verified


Libraries which are managed by the Library Manager in the POU pool

Table 15. Commands in the Library Manager

_cds_icon_libman_add_library.pngAdd Library

Opens the dialog for selecting a library

All libraries installed in the library repository are offered.

_icon_delete_library.pngDelete Library

Removes the currently selected library from the project


Opens the dialog for the display and editing of the properties of the presently selected library


Opens a dialog with details for the presently selected library (general information, contents, properties, license information)

_cds_icon_libman_try_to_reload.pngTry to Reload Library

If you select a library marked as not found, then you can try to load it into the project again using this command.

_cds_icon_libman_download.pngDownload Missing Libraries

Opens a dialog which displays the libraries marked as missing in the Library Manager.

On download, CODESYS scans for these libraries in the download server specified in the project options. After being downloaded, they will be installed automatically.

As long as this dialog is open, the recently installed libraries can be uninstalled.


Opens the Placeholders dialog. The current resolution is displayed and you can edit them there.

_cds_icon_libman_parameter.pngLibrary Parameters

Opens the Library Parameters dialog. The parameters of the libraries which exist in the Library Manager of the application and of the POU pool are displayed there. You can customize the parameters in this dialog.

_icon_library_repository.pngLibrary Repository

Opens the Library Repository dialog for installing and uninstalling libraries and for defining library locations

_cds_icon_libman_icon_legend.pngIcon Legend

Opens the Information dialog with a legend of the icons that display the current status of a library in the list of integrated libraries (see above)


Opens the Library Summary dialog

All libraries referenced in the project are displayed in a tree structure in the dialog, and those libraries which reference these libraries.

  • Display all occurrences in library hierarchy and close dialog command: In the editor of the Library Manager, the libraries in the open tree structure are marked which reference or use this library. Requirement: A library is selected. The Information dialog is closed afterwards.

    This command is also executed when you double-click a library.

. Display of the libraries
  • Managed Library: Name and version of the library

  • Number of Occurrences: Number of locations where this library is referenced by other libraries

When you click + for a library, the libraries, which reference this library, are displayed in the next level down.

_cds_icon_libman_trust_cert.pngTrust Certificate

Only in the context menu of a library selected in the Library Manager, in which the library has been signed with an untrusted certificate

The command turns the untrusted certificate into a trusted certificate and the prepended icon changes from _cds_icon_libman_legacy_lib.png to _cds_icon_libman_signed_lib.png.

Export Library

Available only in the context menu of a library selected in the Library Manager

Opens the default dialog for saving the library file in the file system

Tree structure of all modules of a selected library

Table 16. Contents of the selected <library name> library

All library POUs which were integrated with the library are listed in a tree structure.

Requirement: A library is selected in the upper view.


The usual sorting and search functions are available in the menu bar.

Documentation for the library POU selected in the lower left view


The documentation of implementation libraries has to be generated one time. This is done using the Click to update the library documentation command.

Tab: Inputs/Outputs

Interface (inputs/outputs) of the library POU

Tab: Graphical

Graphical display of the module

Tab: Documentation

Documentation for the library POU

Note: As a library developer, you need to pay strict attention to the rules for documentation inclusion in "Guidelines for library development".

For more information, see: Library Development Summary

Tab: Library Parameters

Requirement: The library project contains an object with library parameters.

The Open configuration dialog command is located on the tab. This command opens the Library Parameters dialog.