Errata exists for this version of the document.

The ExclusiveLimitAlarmType is used to specify the common behaviour for Alarm Types with multiple mutually exclusive limits. The ExclusiveLimitAlarmType is illustrated in Figure 18.

Figure 18 – ExclusiveLimitAlarmType

The ExclusiveLimitAlarmType is formally defined in Table 63.

Table 63 – ExclusiveLimitAlarmType definition

Attribute	Value
BrowseName	ExclusiveLimitAlarmType
IsAbstract	False
References	NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the LimitAlarmType defined in clause 5.8.11.
HasSubtype	ObjectType	ExclusiveLevelAlarmType	Defined in Clause 5.8.14.3
HasSubtype	ObjectType	ExclusiveDeviationAlarmType	Defined in Clause 5.8.15.3
HasSubtype	ObjectType	ExclusiveRateOfChangeAlarmType	Defined in Clause 5.8.16.3
HasComponent	Object	LimitState		ExclusiveLimitStateMachineType	Mandatory

The LimitState is a sub state of the ActiveState and has an IsTrueSubStateOf reference to the ActiveState. The LimitState represents the actual limit that is violated in an instance of ExclusiveLimitAlarmType. When the ActiveState of the AlarmConditionType is inactive the LimitState shall not be available and shall return NULL on read. Any Events that subscribe for fields from the LimitState when the ActiveState is inactive shall return a NULL for these unavailable fields.