If the combination of IO-Link Error Code and Additional Code is listed in the IODD StandardDefinitions (see IODD Specification), the server shall use text specified there with the appropriate locale as localizedText. Servers may provide vendor-specific translations to other languages. (In this case they have to adjust the value of locale as well.)

If the combination of IO-Link Error Code and Additional Code is vendor-specific (0x8101 to 0x81FF) the IODD should contain an entry in its ErrorTypeCollection.

  • If the IODD does not contain a corresponding entry in its ErrorTypeCollection no string shall be provided at all. This is indicated by giving stringTable index -1 as localizedText. Note: IODDs following IODD Specification 1.0.1 do not have an ErrorTypeCollection at all.
  • If the IODD contains a corresponding entry in its ErrorTypeCollection, the localizedText contains the text referenced by the XML property "Name" of the XML element "ErrorType". The additionalInfo contains the text referenced by the XML property "Description" of the XML element "ErrorType", if the description is available. In all other cases the content of additionalInfo is vendor-specific, but usually an empty string.

As a result of this, the StdErrorTypeRef elements of the ErrorTypeCollection in the IODD might be ignored by the OPC UA server.