This ObjectTypedefines the structure of a Block Object. Figure 14depicts the BlockTypehierarchy. It is formally defined in Table 33.

Figure 14– 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 33– BlockType definition

Attribute	Value
BrowseName	BlockType
IsAbstract	True
References	NodeClass	BrowseName	DataType	TypeDefinition	Other
Subtype of the TopologyElementTypedefined in 4.2
0:HasProperty	Variable	RevisionCounter	0:Int32	0:PropertyType	O
0:HasProperty	Variable	ActualMode	0:LocalizedText	0:PropertyType	O
0:HasProperty	Variable	PermittedMode	0:LocalizedText []	0:PropertyType	O
0:HasProperty	Variable	NormalMode	0:LocalizedText []	0:PropertyType	O
0:HasProperty	Variable	TargetMode	0:LocalizedText []	0:PropertyType	O
Conformance Units
DI Blocks

BlockTypeis a subtype of TopologyElementTypeand inherits the elements for Parameters, Methodsand FunctionalGroups.

The BlockTypeis abstract. There will be no instances of a BlockTypeitself, but there will be instances of subtypes of this Type. In this specification, the term Blockgenerically refers to an instance of any subtype of the BlockType.

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

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

The ActualMode Propertyreflects the current mode of operation.

The PermittedModedefines the modes of operation that are allowed for the Blockbased on application requirements.

The NormalModeis the mode the Blockshould be set to during normal operating conditions. Depending on the Blockconfiguration, multiple modes may exist.

The TargetModeindicates the mode of operation that is desired for the Block. Depending on the Blockconfiguration, multiple modes may exist.