This ObjectType defines the structure of a Block Object. Figure 17 depicts the BlockType hierarchy. It is formally defined in Table 30.

Figure 17 – BlockType hierarchy

FFBlockType and PROFIBlockType are examples. They are not further defined in this specification. It is expected that industry groups will standardize general purpose BlockTypes.

Table 30 – BlockType definition

Attribute	Value
BrowseName	BlockType
IsAbstract	True
References	NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the TopologyElementType defined in 5.2
HasProperty	Variable	RevisionCounter	Int32	PropertyType	Optional
HasProperty	Variable	ActualMode	LocalizedText	PropertyType	Optional
HasProperty	Variable	PermittedMode	LocalizedText[]	PropertyType	Optional
HasProperty	Variable	NormalMode	LocalizedText[]	PropertyType	Optional
HasProperty	Variable	TargetMode	LocalizedText[]	PropertyType	Optional

BlockType is a subtype of TopologyElementType and inherits the elements for Parameters, Methods and FunctionalGroups.

The BlockType is abstract. There will be no instances of a BlockType itself, but there will be instances of subtypes of this Type. In this specification, the term Block generically refers to an instance of any subtype of the BlockType.

The RevisionCounter is an incremental counter indicating the number of times the static data within the Block has been modified. A value of -1 indicates that no revision information is available.

The following Properties refer to the Block Mode (e.g. “Manual”, “Out of Service”).

The ActualMode Property reflects the current mode of operation.

The PermittedMode defines the modes of operation that are allowed for the Block based on application requirements.

The NormalMode is the mode the Block should be set to during normal operating conditions. Depending on the Block configuration, multiple modes may exist.

The TargetMode indicates the mode of operation that is desired for the Block. Depending on the Block configuration, multiple modes may exist.