EtherCAT SubDevice Information (ESI) File

An EtherCAT SubDevice Information (ESI) file is a .xml file that describes EtherCAT SubDevices. It contains descriptions of the features and properties of the device, from process data configuration to the physical ports of the device. RMCTools needs the ESI file for each device in order to add it to the network and allow it to be configured.

Before configuring an EtherCAT network, you must obtain the proper ESI file for each device on the network and then add them in the EtherCAT ESI Manager.

Obtaining ESI Files

ESI files are usually available from the SubDevice manufacturer’s website. Some SubDevices may require installation of their configuration software in order to access the ESI file.

When searching for ESI files, be aware that terminology may vary. The ESI files themselves have a .xml extension but are frequently provided in a .zip file. Manufacturers may describe the ESI file using varying terminology, including but not limited to:

EtherCAT ESI File
Device Description File
EtherCAT Slave File
Configuration File

Generally, if you search for “EtherCAT file” or “EtherCAT ESI” on the manufacturer’s website, you will find the file.

Most manufacturers provide many different ESI files. Make sure to choose the correct file for your specific device.

Adding SubDevice ESI Files

Once you have obtained an ESI file (or many files) and saved it to your PC, add it to the ESI Manager:

In RMCTools, on the Tools menu, select EtherCAT ESI Manager.
In the ESI Manager, click Add File. Browse to the ESI file that you have downloaded, select it and click Open.

Optionally, click Add Folder to browse to a folder location on your PC that contains multiple ESI files that you have already downloaded. This will add all the ESI files from that location at once.
Wait for the ESI Manager to process the selected file, then close the dialog.

Note on including many ESI files: Some manufacturers include ESI files for many SubDevices in a single download. If that isn’t necessary for your project, you may want to consider adding only the ESI files for the specific SubDevices you require. Otherwise, if you have installed many ESI files, the processing time in the ESI Manager may be very long for subsequent files, as RMCTools needs to process all the existing files each time. If you did accidentally add many more ESI files than necessary, you can remove them.

Where ESI Files Reside

Imported ESI Files are saved on the local machine and available to all users of the PC. Therefore, any RMCTools project you open on that PC will list those ESI files in the EtherCAT ESI Manager. You can export ESI files from the ESI Manager.

Some parts of the ESI file are included in the RMCTools project itself (also included in the download to the RMC), enough for RMCTools and the RMC to fully interact with the SubDevice. When opening an RMCTools project on a PC which does not have the ESI files installed, this subset will allow the project to fully function properly. However, that subset is not sufficient for adding new SubDevices to the network.

Viewing ESI Files

The EtherCAT ESI Manager displays all the ESI files that you have added on the PC, listed by manufacturer name.

Click the expand icon to view the individual ESI files for a manufacturer and click the second expand icon to view the devices covered by that particular ESI file.

Removing ESI Files

To remove an ESI file, in the EtherCAT ESI Manager, in the ESI Files list, choose the .xml file and click Delete.

To remove all the ESI files for a manufacturer, in the ESI Files list, choose the manufacturer and click Delete.

Exporting ESI Files

To export an ESI file, in the EtherCAT ESI Manager, in the ESI Files list, choose the .xml file and click Export.

To export all the ESI files for a manufacturer, in the ESI Files list, choose the manufacturer and click Export.

An exported ESI file can be treated as a normal ESI file and added to the EtherCAT ESI Manager on a different PC.

ESI Files versus SCI Files

RMCTools needs the ESI file to add a SubDevice to the EtherCAT network. Once it is added, the user will then configure that SubDevice. For large projects, the user may want to add many identical devices with the same configuration. The user can export that SubDevice, with its configuration, to a SubDevice Configuration Information (SCI) file, also referred to as a Preconfigured SubDevice. The SCI file can then be used instead of the ESI file to add new SubDevices with the same configuration. See SubDevice Configuration Information (SCI) file for details.