scope:

This prestandard defines FLN-objects and FLN-services to be used on a field level for system neutral exchange of data for HVAC applications. This prestandard defines the semantics of the objects and the abstract services applicable to them and it defines an optional syntax to be used to exchange data with a communication front-end unit. The syntax of the object data on the underlying communication (bus) protocol is not within the scope of this prestandard. In particular, this prestandard provides a set of objects and services which are: - to be used by the application programme interface may subsequently be defined in an amendment to this prestandard if TC 247 considers this appropriate; - to be used in an interface between the HBES device and a portable communication front-end, defined as level D or as a process-interface in EN 50090-2-1; - to be incorporated and mapped by the providers of the field level protocols; - the objects to be incorporated in the protocol provider's set of objects and to be encoded in APDUs of the respective protocol; - the services to be mapped by the protocol providers onto appropriate services of their respective protocols.