The Severity of a Conditionis inherited from the base Eventmodel defined in OPC 10000-5. It indicates the urgency of the Conditionand is also commonly called ‘priority’, especially in relation to Alarmsin the ProcessConditionClassType.
A Comment is a user generated string that is to be associated with a certain state of a Condition.
Quality refers to the quality of the data value(s) upon which this Conditionis based. Since a Conditionis usually based on one or more Variables, the Conditioninherits the quality of these Variables. E.g., if the process value is “Uncertain”, the “Level Alarm” Conditionis also questionable. If more than one variable is represented by a given condition or if the condition is from an underlining system and no direct mapping to a variable is available, it is up to the application to determine what quality is displayed as part of the condition.