User Manual

Alarm management
Alarm response of the function blocks
9
CM110664en_07 149 | 353
Trend Log
The Trend Log function has an Intrinsic Reporting mechanism, but does not
issue OFFNORMAL alarms.
● A FAULT alarm is generated as soon as the [Rlb] property of the function
block assumes any value other than NO_FAULT_DETECTED. In particular,
this is the case when [Rlb] changes from a value not equal to
NO_FAULT_DETECTED to another value not equal to
NO_FAULT_DETECTED.
● A FAULT alarm will disappear as soon as the [Rlb] property of the function
block changes from a value not equal to NO_FAULT_DETECTED back to the
value NO_FAULT_DETECTED.
An event is generated when:
● The record count exceeds the record count value [RecCnt] set via the
notification threshold [NotifThd], that is, the local non-volatile trend
memory is overflowing.
Event Enrollment
The Event Enrollment object monitors referenced BACnet properties in other
objects. The referenced property can be located in the local device or in
another device.
Monitoring details for a property value are defined by means of event
algorithms. An event algorithm has a specific parameter. Event algorithms are
the same as for Intrinsic Reporting. Intrinsic Reporting uses a subset of the
possible event algorithms of Event Enrollment.
Event_Type Event_State Event_Parameters Data type
CHANGE_OF_BITSTRING NORMAL
OFFNORMAL
Time_Delay
Bitmask
List_Of_Bitstring_Values
Unsigned
BIT STRING
list of BIT STRING
CHANGE_OF_STATE NORMAL
OFFNORMAL
Time_Delay
List_Of_Values
Unsigned
list of BACnetPropertyStates
CHANGE_OF_VALUE NORMAL Time_Delay
Bitmask
Referenced_Property_Increment
Unsigned
BIT STRING
choice {BIT STRING, REAL}
COMMAND_FAILURE NORMAL
OFFNORMAL
Time_Delay
Feedback_Property_Reference
Unsigned
BACnetDeviceObjectPropertyRe
ference
Alarm response
Event message
Event algorithms