823   ValKind for structured data attributes

Created: 20 Feb 2012

Status: In Force (green)

Part: Part 6 (2009-12; Edition 2)

Links:

Page: 100

Clause: 9.5.4.1

Paragraph:

Category: Issue may impact interoperability of implementations of Edition 2

Issue

In the SCL schema it is allowed to define valKind attributes for structured data attributes (for the DA element) in the DataTypeTemplates section. It is then not clear what its meaning shall be for its child data attributes, esp. since the default value is "Set".
For instance, if a structured data attribute (e.g., Unit) has an explicit valKind="RO", and its child attributes SIUnit and multiplier have none (in which case the valKind is "Set" by default), the valKind of the structured data attribute (Unit) is irrelevant.

Note that there is no way to provide a valKind for the instance of a structured data attribute instance (in the IED section, valKind can only be overridden for DAIs, not SDIs).

Proposal

Handle valKind attribute like the Val sub-elements: even if legal from an SCL schema point of view, the valKind attribute should be considered as irrelevant (ignored) for structured data attributes (for DA elements in the DataTypeTemplates section).