BACnet PTP Serial Driver Manual
Page 22 of 34
Appendix A.8. Reliability_Option
The Reliability_Option parameter selects the rules by which the BACnet server determines the Reliability
property of a BACnet object whose present value is read from a Remote Server Node.
There are two important events that can affect the reliability of a BACnet object:
•
The responsible Remote Server Node is offline, i.e. the data cannot be updated.
•
A BACnet write request has been received by the BACnet Server. This causes the corresponding
FieldServer data object to be expired until its value is updated by the next successful Read operation.
There are three options for translating these conditions to BACnet Reliability values:
Track_Object_Status
The Reliability property mirrors the internal data object state, i.e. if the Remote
Server Node is offline or the data is expired by a BACnet write, the Reliability
is marked Unreliable-Other.
Track_Node_Status
(default)
The reported reliability is good unless the Remote_Server_Node is offline, in
which case the Reliability is Unreliable-Other. Reliability is not affected by
data expiry following a BACnet write.
Always_Reliable
The BACnet Server always reports good data reliability, regardless of the
status of communications with the Remote Server Node.
Example
Adapters
Adapter
, Protocol
, Reliability_Option
N1
, BACnet_IP , Track_Node_Status
NOTE: This setting applies to all BACnet Nodes configured for a given BACnet Connection.
