The table below lists the parameters in the Event Parameters attribute. For a description of the algorithms to which these parameters apply, refer to ANSI/ASHRAE BACnet Standard 135 - 1995.
Parameter |
Description |
---|---|
Bitmask |
This parameter applies to the Change of Bitstring event algorithm and the Change of Value event algorithm in the special case where the referenced attribute is a Bit String data type. It represents a bitmask that is used to indicate which bits in the referenced attribute are monitored by the algorithm. A value of one in a bit position indicates that the bit in this position in the referenced attribute is monitored by the algorithm. A value of zero in a bit position indicates that the bit in this position in the referenced attribute is not significant for the purpose of detecting this Change of Bitstring or Change of Value. |
Deadband High Diff Limit Low Diff Limit High Limit Low Limit |
These parameters apply to these event algorithms: Signed Out of Range, Unsigned Out of Range, Unsigned Range, Floating Limit, Out of Range, Double Out of Range. The only exception is that Deadband does not apply to Unsigned Range. |
Feedback Property Reference |
This parameter (BACnet Object Property Reference) applies to the Command Failure algorithm. Feedback Property Reference identifies the object and attribute that provides the feedback to ensure that the commanded attribute changes value. This attribute may reference only object properties that have lists of true and false values. |
List of Bitstring Values |
This is a list that applies to the Change of Bitstring event algorithm. This list defines the set of states for which the referenced attribute is Offnormal. Only the bits indicated by the Bitmask are significant. If the value of the referenced attribute changes to one of the values in the List of Bitstring Values, then the Event State attribute of the Event Enrollment object makes a transition To Offnormal and sends the appropriate notifications. |
List of Values |
This is a list of BACnet Property States that applies to the Change of State event algorithm. This event algorithm applies to referenced properties that have discrete or lists of values. The List of Values is a subset of the possible values that the attribute may have. If the value of the referenced attribute changes to one of the values in the List of Values, then the Event State attribute of the Event Enrollment object makes a transition to To Offnormal and sends the appropriate notifications. |
COV Increment |
This parameter applies to the Change of Value event algorithm. It represents the increment by which the referenced attribute must change in order for the event to occur. |
Setpoint Reference |
This parameter (BACnet Object Property Reference), applies to the Floating Limit event algorithm. Setpoint Reference indicates the setpoint reference for the reference attribute interval. |
Time Delay |
This parameter applies to all event types and represents the seconds that the conditions monitored by the event algorithm persist before an event notification is issued. |
Referenced Property Increment |
This parameter represents the increment by which the referenced property must change for an event to occur. |